Neoplastic Process

MeSH ID: T191

Related Concepts:

  • Abdominal Neoplasms [M0000008]
  • Acanthoma [M0464093]
    A neoplasm composed of squamous or epidermal cells.
  • Acanthoma, Clear Cell [M0464094]
    Benign tumor found mostly frequently on the legs.
  • Acanthoma, Pilar Sheath [M0464095]
    Benign follicular tumor usually of the upper lip.
  • Acrospiroma, Eccrine [M0027479]
    A tumor derived from eccrine sweat duct epithelium which may be intra-epidermal (hidro-acanthoma simplex), juxta-epidermal (eccrine poroma) or intradermal (dermal duct tumor). They are comparatively uncommon. There is no indication that heredity or external agents cause these tumors. (Rook et al., Textbook of Dermatology, 4th ed, p2409)
  • ACTH-Secreting Pituitary Adenoma [M0470981]
    A pituitary adenoma which secretes ADRENOCORTICOTROPIN, leading to CUSHING DISEASE.
  • Adamantinoma [M0474809]
    A locally aggressive, osteolytic neoplasm of the long bones, probably of epithelial origin and most often involving the TIBIA.
  • Adenocarcinoma [M0000355]
    A malignant epithelial tumor with a glandular organization.
  • Adenocarcinoma, Basal Cell [M0000356]
  • Adenocarcinoma, Bronchiolo-Alveolar [M0003433]
    A carcinoma thought to be derived from epithelium of terminal bronchioles, in which the neoplastic tissue extends along the alveolar walls and grows in small masses within the alveoli. Involvement may be uniformly diffuse and massive, or nodular, or lobular. The neoplastic cells are cuboidal or columnar and form papillary structures. Mucin may be demonstrated in some of the cells and in the material in the alveoli, which also includes denuded cells. Metastases in regional lymph nodes, and in even more distant sites, are known to occur, but are infrequent. (From Stedman, 25th ed)
  • Adenocarcinoma, Clear Cell [M0027491]
    An adenocarcinoma characterized by the presence of varying combinations of clear and hobnail-shaped tumor cells. There are three predominant patterns described as tubulocystic, solid, and papillary. These tumors, usually located in the female reproductive organs, have been seen more frequently in young women since 1970 as a result of the association with intrauterine exposure to diethylstilbestrol. (From Holland et al., Cancer Medicine, 3d ed)
  • Adenocarcinoma, Endometrioid [M0485456]
  • Adenocarcinoma, Follicular [M0027492]
    An adenocarcinoma of the thyroid gland, in which the cells are arranged in the form of follicles. (From Dorland, 27th ed)
  • Adenocarcinoma, Mucinous [M0003439]
    An adenocarcinoma producing mucin in significant amounts. (From Dorland, 27th ed)
  • Adenocarcinoma, Oxyphilic [M0000357]
  • Adenocarcinoma, Papillary [M0000361]
    An adenocarcinoma containing finger-like processes of vascular connective tissue covered by neoplastic epithelium, projecting into cysts or the cavity of glands or follicles. It occurs most frequently in the ovary and thyroid gland. (Stedman, 25th ed)
  • Adenocarcinoma, Scirrhous [M0003443]
    An adenocarcinoma with a hard (Greek skirrhos, hard) structure owing to the formation of dense connective tissue in the stroma. (From Dorland, 27th ed)
  • Adenocarcinoma, Sebaceous [M0027494]
    A malignant tumor composed of cells showing differentiation toward sebaceous epithelium. The tumor is solitary, firm, somewhat raised, more or less translucent, and covered with normal or slightly verrucose epidermis. It may be yellow or orange. The face and scalp are the commonest sites. The growth can be slow or rapid but metastasis is uncommon. Surgery cures most of the cases. (From Rook et al., Textbook of Dermatology, 4th ed, pp2403-4)
  • Adenocarcinoma, Tubular [M0000360]
  • Adenofibroma [M0000362]
    A benign neoplasm composed of glandular and fibrous tissues, with a relatively large proportion of glands. (Stedman, 25th ed)
  • Adenolymphoma [M0000366]
    A benign tumor characterized histologically by tall columnar epithelium within a lymphoid tissue stroma. It is usually found in the salivary glands, especially the parotid.
  • Adenoma [M0000367]
    A benign epithelial tumor with a glandular organization.
  • Adenoma, Acidophil [M0000376]
    A benign tumor, usually found in the anterior lobe of the pituitary gland, whose cells stain with acid dyes. Such pituitary tumors may give rise to excessive secretion of growth hormone, resulting in gigantism or acromegaly. A specific type of acidophil adenoma may give rise to nonpuerperal galactorrhea. (Dorland, 27th ed)
  • Adenoma, Basal Cell [M0000368]
  • Adenoma, Basophil [M0000374]
    A small tumor of the anterior lobe of the pituitary gland whose cells stain with basic dyes. It may give rise to excessive secretion of ACTH, resulting in CUSHING SYNDROME. (Dorland, 27th ed)
  • Adenoma, Bile Duct [M0004226]
    A benign tumor of the intrahepatic bile ducts.
  • Adenoma, Chromophobe [M0000375]
    A benign tumor of the anterior pituitary in which the cells do not stain with acidic or basic dyes.
  • Adenoma, Follicular [M0000369]
  • Adenoma, Islet Cell [M0011744]
    A benign tumor of the pancreatic ISLET CELLS. Usually it involves the INSULIN-producing PANCREATIC BETA CELLS, as in INSULINOMA, resulting in HYPERINSULINISM.
  • Adenoma, Liver Cell [M0027477]
    A benign epithelial tumor of the LIVER.
  • Adenoma, Microcystic [M0000370]
  • Adenoma, Monomorphic [M0000371]
  • Adenoma, Oxyphilic [M0027478]
    A usually benign glandular tumor composed of oxyphil cells, large cells with small irregular nuclei and dense acidophilic granules due to the presence of abundant MITOCHONDRIA. Oxyphil cells, also known as oncocytes, are found in oncocytomas of the kidney, salivary glands, and endocrine glands. In the thyroid gland, oxyphil cells are known as Hurthle cells and Askanazy cells.
  • Adenoma, Papillary [M0000372]
  • Adenoma, Pleomorphic [M0013963]
    A benign, slow-growing tumor, most commonly of the salivary gland, occurring as a small, painless, firm nodule, usually of the parotid gland, but also found in any major or accessory salivary gland anywhere in the oral cavity. It is most often seen in women in the fifth decade. Histologically, the tumor presents a variety of cells: cuboidal, columnar, and squamous cells, showing all forms of epithelial growth. (Dorland, 27th ed)
  • Adenoma, Sweat Gland [M0010344]
    A benign neoplasm derived from epithelial cells of sweat glands. (Stedman, 25th ed)
  • Adenoma, Trabecular [M0000373]
  • Adenoma, Villous [M0027482]
    An adenoma of the large intestine. It is usually a solitary, sessile, often large, tumor of colonic mucosa composed of mucinous epithelium covering delicate vascular projections. Hypersecretion and malignant changes occur frequently. (Stedman, 25th ed)
  • Adenomatoid Tumor [M0027483]
    A small, circumscribed, benign tumor of the genital tract, composed of small glandlike spaces lined by flattened or cuboidal mesothelium-like cells. (From Dorland, 27th ed)
  • Adenomatosis, Pulmonary [M0027484]
    A neoplastic disease in which the alveoli and distal bronchi are filled with mucus and mucus-secreting columnar epithelial cells. It is characterized by abundant, extremely tenacious sputum, chills, fever, cough, dyspnea, and pleuritic pain. (Stedman, 25th ed)
  • Adenomatous Polyposis Coli [M0017238]
    A polyposis syndrome due to an autosomal dominant mutation of the APC genes (GENES, APC) on CHROMOSOME 5. The syndrome is characterized by the development of hundreds of ADENOMATOUS POLYPS in the COLON and RECTUM of affected individuals by early adulthood. The lifetime risk of colorectal cancer in these patients reaches 100 percent by age 60.
  • Adenomatous Polyps [M0027485]
    Benign neoplasms derived from glandular epithelium. (From Stedman, 25th ed)
  • Adenomyoma [M0027423]
    A benign neoplasm of muscle (usually smooth muscle) with glandular elements. It occurs most frequently in the uterus and uterine ligaments. (Stedman, 25th ed)
  • Adenosarcoma [M0027424]
    A malignant neoplasm arising simultaneously or consecutively in mesodermal tissue and glandular epithelium of the same part. (Stedman, 25th ed)
  • Adrenal Cancer [M0331848]
  • Adrenal Cortex Neoplasms [M0000481]
    Tumors or cancers of the ADRENAL CORTEX.
  • Adrenal Gland Neoplasms [M0000485]
    Tumors or cancer of the ADRENAL GLANDS.
  • Adrenal Rest Tumor [M0000490]
    Neoplasm derived from displaced cells (rest cells) of the primordial ADRENAL GLANDS, generally in patients with CONGENITAL ADRENAL HYPERPLASIA. Adrenal rest tumors have been identified in TESTES; LIVER; and other tissues. They are dependent on ADRENOCORTICOTROPIN for growth and adrenal steroid secretion.
  • Adrenocortical Adenoma [M0027475]
    A benign neoplasm of the ADRENAL CORTEX. It is characterized by a well-defined nodular lesion, usually less than 2.5 cm. Most adrenocortical adenomas are nonfunctional. The functional ones are yellow and contain LIPIDS. Depending on the cell type or cortical zone involved, they may produce ALDOSTERONE; HYDROCORTISONE; DEHYDROEPIANDROSTERONE; and/or ANDROSTENEDIONE.
  • Adrenocortical Cancer [M0331834]
  • Adrenocortical Carcinoma [M0027496]
    A malignant neoplasm of the ADRENAL CORTEX. Adrenocortical carcinomas are unencapsulated anaplastic (ANAPLASIA) masses sometimes exceeding 20 cm or 200 g. They are more likely to be functional than nonfunctional, and produce ADRENAL CORTEX HORMONES that may result in hypercortisolism (CUSHING SYNDROME); HYPERALDOSTERONISM; and/or VIRILISM.
  • Adult Optic Nerve Glioma [M0335899]
  • African Lymphoma [M0483383]
  • Aleukemic Leukemia Cutis [M0355301]
    A form of aleukemic leukemia where lesions containing abnormal leukocytes can be found within the skin.
  • Ameloblastoma [M0000883]
    An immature epithelial tumor of the JAW originating from the epithelial rests of Malassez or from other epithelial remnants of the ENAMEL from the developmental period. It is a slowly growing tumor, usually benign, but displays a marked propensity for invasive growth.
  • Anal Cancer [M0332111]
  • Anal Gland Neoplasms [M0001061]
    Tumors or cancer of the anal gland.
  • Anaplasia [M0001077]
    Loss of structural differentiation and useful function of neoplastic cells.
  • Anaplastic Astrocytoma [M0336533]
  • Anaplastic Ependymoma [M0337466]
  • Anaplastic Oligodendroglioma [M0336853]
  • Angioblastic Meningioma [M0337827]
  • Angiofibroma [M0027557]
    A benign neoplasm of fibrous tissue in which there are numerous small and large, frequently dilated, vascular channels. (Stedman, 25th ed)
  • Angiokeratoma [M0001190]
    A vascular, horny neoplasm of the skin characterized by TELANGIECTASIS and secondary epithelial changes including acanthosis and hyperkeratosis.
  • Angiolipoma [M0027435]
    A benign neoplasm composed of a mixture of adipose tissue and blood vessels. (Dorland, 27th ed)
  • Angiomatous Meningioma [M0337828]
  • Angiomyolipoma [M0027436]
    A benign tumor containing vascular, adipose, and muscle elements. It occurs most often in the kidney with smooth muscle elements (angiolipoleiomyoma) in association with tuberous sclerosis. (Dorland, 27th ed)
  • Angiomyoma [M0027458]
    A benign tumor consisting of vascular and smooth muscle elements.
  • Anus Neoplasms [M0001529]
    Tumors or cancer of the ANAL CANAL.
  • Appendiceal Cancer [M0332117]
  • Appendiceal Neoplasms [M0001609]
    Tumors or cancer of the APPENDIX.
  • Apudoma [M0001633]
    A general term collectively applied to tumors associated with the APUD CELLS series, irrespective of their specific identification.
  • Arachnoidal Cerebellar Sarcoma, Circumscribed [M0337103]
  • Argentaffinoma [M0003423]
  • Astroblastoma [M0336846]
  • Astrocytoma [M0001891]
    Neoplasms of the brain and spinal cord derived from glial cells which vary from histologically benign forms to highly anaplastic and malignant tumors. Fibrillary astrocytomas are the most common type and may be classified in order of increasing malignancy (grades I through IV). In the first two decades of life, astrocytomas tend to originate in the cerebellar hemispheres; in adults, they most frequently arise in the cerebrum and frequently undergo malignant transformation. (From Devita et al., Cancer: Principles and Practice of Oncology, 5th ed, pp2013-7; Holland et al., Cancer Medicine, 3d ed, p1082)
  • Astrocytoma, Grade I [M0336535]
  • Astrocytoma, Grade II [M0336534]
  • Astrocytoma, Malignant, Optic Nerve [M0335898]
  • Astrocytoma, Protoplasmic [M0336536]
  • Astrocytoma, Subependymal Giant Cell [M0009272]
  • Auricular Cancer [M0332359]
  • Avian Leukosis [M0002025]
    A group of transmissible viral diseases of chickens and turkeys. Liver tumors are found in most forms, but tumors can be found elsewhere.
  • Basal Cell Cancer [M0333073]
  • Basal Cell Nevus Syndrome [M0002195]
    Hereditary disorder consisting of multiple basal cell carcinomas, odontogenic keratocysts, and multiple skeletal defects, e.g., frontal and temporoparietal bossing, bifurcated and splayed ribs, kyphoscoliosis, fusion of vertebrae, and cervicothoracic spina bifida. Genetic transmission is autosomal dominant.
  • Benign Brenner Tumor [M0472443]
  • Benign Cerebellar Neoplasms [M0334441]
  • Benign Cranial Nerve Neoplasms [M0335871]
  • Benign Hypothalamic Neoplasms [M0335325]
  • Benign Infratentorial Neoplasms [M0335407]
  • Benign Meningeal Neoplasms [M0337067]
  • Benign Meningioma [M0337825]
  • Benign Neoplasms [M0014586]
  • Benign Neoplasms, Brain [M0334228]
  • Benign Optic Nerve Neoplasm [M0335890]
  • Benign Optic Nerve Sheath Neoplasms [M0335891]
  • Benign Supratentorial Neoplasms [M0336214]
  • Bile Duct Cancer [M0332158]
  • Bile Duct Neoplasms [M0002479]
    Tumors or cancer of the BILE DUCTS.
  • Biliary Tract Cancer [M0332162]
  • Biliary Tract Neoplasms [M0002492]
    Tumors or cancer in the BILIARY TRACT including the BILE DUCTS and the GALLBLADDER.
  • Bone Cancer [M0482438]
  • Bone Marrow Neoplasms [M0028434]
    Neoplasms located in the bone marrow. They are differentiated from neoplasms composed of bone marrow cells, such as MULTIPLE MYELOMA. Most bone marrow neoplasms are metastatic.
  • Bone Neoplasms [M0002792]
    Tumors or cancer located in bone tissue or specific BONES.
  • Bovine Leukemia [M0025296]
  • Bowen's Disease [M0002852]
    A persistent progressive non-elevated red scaly or crusted plaque which is due to an intradermal carcinoma and is potentially malignant. Atypical squamous cells proliferate through the whole thickness of the epidermis. The lesions may occur anywhere on the skin surface or on mucosal surfaces. The cause most frequently found is trivalent arsenic compounds. Freezing, cauterization or diathermy coagulation is often effective. (From Rook et al., Textbook of Dermatology, 4th ed, pp2428-9)
  • Brain Cancer [M0334225]
  • Brain Neoplasms [M0002885]
    Neoplasms of the intracranial components of the central nervous system, including the cerebral hemispheres, basal ganglia, hypothalamus, thalamus, brain stem, and cerebellum. Brain neoplasms are subdivided into primary (originating from brain tissue) and secondary (i.e., metastatic) forms. Primary neoplasms are subdivided into benign and malignant forms. In general, brain tumors may also be classified by age of onset, histologic type, or presenting location in the brain.
  • Brain Stem Neoplasms [M0328182]
    Benign and malignant intra-axial tumors of the MESENCEPHALON; PONS; or MEDULLA OBLONGATA of the BRAIN STEM. Primary and metastatic neoplasms may occur in this location. Clinical features include ATAXIA, cranial neuropathies (see CRANIAL NERVE DISEASES), NAUSEA, hemiparesis (see HEMIPLEGIA), and quadriparesis. Primary brain stem neoplasms are more frequent in children. Histologic subtypes include GLIOMA; HEMANGIOBLASTOMA; GANGLIOGLIOMA; and EPENDYMOMA.
  • Brain Stem Neoplasms, Primary [M0334271]
  • Brain Tumor, Primary [M0334239]
  • Brain Tumor, Recurrent [M0334240]
  • Branchioma [M0002890]
    A tumor derived from branchial epithelium or branchial rests. (Dorland, 27th ed)
  • Breast Cancer [M0002909]
  • Breast Neoplasms [M0002910]
    Tumors or cancer of the human BREAST.
  • Breast Neoplasms, Male [M0027832]
    Any neoplasms of the male breast. These occur infrequently in males in developed countries, the incidence being about 1% of that in females.
  • Brenner Tumor [M0002918]
    A smooth, solid or cystic fibroepithelial (FIBROEPITHELIAL NEOPLASMS) tumor, usually found in the OVARIES but can also be found in the adnexal region and the KIDNEYS. It consists of a fibrous stroma with nests of epithelial cells that sometimes resemble the transitional cells lining the urinary bladder. Brenner tumors generally are benign and asymptomatic. Malignant Brenner tumors have been reported.
  • Bronchial Neoplasms [M0002965]
  • Burkitt Lymphoma [M0003058]
    A form of undifferentiated malignant LYMPHOMA usually found in central Africa, but also reported in other parts of the world. It is commonly manifested as a large osteolytic lesion in the jaw or as an abdominal mass. B-cell antigens are expressed on the immature cells that make up the tumor in virtually all cases of Burkitt lymphoma. The Epstein-Barr virus (HERPESVIRUS 4, HUMAN) has been isolated from Burkitt lymphoma cases in Africa and it is implicated as the causative agent in these cases; however, most non-African cases are EBV-negative.
  • Cancer [M0014584]
  • Cancer of Cecum [M0332204]
  • Cancer of Colon [M0332276]
  • Cancer of Digestive System [M0332317]
  • Cancer of Esophagus [M0332429]
  • Cancer of Eye [M0332431]
  • Cancer of Gallbladder [M0332447]
  • Cancer of Gastrointestinal Tract [M0449005]
  • Cancer of Head [M0392810]
  • Cancer of Head and Neck [M0332484]
  • Cancer of Intestines [M0332593]
  • Cancer of Jaw [M0332598]
  • Cancer of Kidney [M0332600]
  • Cancer of Larynx [M0332985]
  • Cancer of Lip [M0332990]
  • Cancer of Liver [M0337710]
  • Cancer of Mediastinum [M0333005]
  • Cancer of Mouth [M0337712]
  • Cancer of Muscle [M0333014]
  • Cancer of Nasopharynx [M0333072]
  • Cancer of Neck [M0392809]
  • Cancer of Nose [M0333145]
  • Cancer of Oropharnyx [M0333159]
  • Cancer of Pancreas [M0333232]
  • Cancer of Parotid [M0333236]
  • Cancer of Pelvis [M0333237]
  • Cancer of Penis [M0333240]
  • Cancer of Pharynx [M0333257]
  • Cancer of Rectum [M0333266]
  • Cancer of Salivary Gland [M0333354]
  • Cancer of Skin [M0333435]
  • Cancer of Spleen [M0333442]
  • Cancer of Stomach [M0333444]
  • Cancer of Testis [M0333446]
  • Cancer of the ILEUM [M0446231]
  • Cancer of the Jejunum [M0446229]
  • Cancer of the Uterine Cervix [M0003943]
  • Cancer of Thymus [M0333537]
  • Cancer of Tongue [M0333622]
  • Cancer of Tonsil [M0333619]
  • Cancer of Ureter [M0333627]
  • Cancer of Urethra [M0333639]
  • Cancer of Urinary Tract [M0333649]
  • Cancer of Uterus [M0333656]
  • Cancer of Vulva [M0333665]
  • Cancer, Embryonal [M0333129]
  • Cancer, Embryonal and Mixed [M0333130]
  • Cancer, Second Primary [M0333142]
  • Cancer, Supratentorial [M0336213]
  • Carcinoid Tumor [M0003421]
    A usually small, slow-growing neoplasm composed of islands of rounded, oxyphilic, or spindle-shaped cells of medium size, with moderately small vesicular nuclei, and covered by intact mucosa with a yellow cut surface. The tumor can occur anywhere in the gastrointestinal tract (and in the lungs and other sites); approximately 90% arise in the appendix. It is now established that these tumors are of neuroendocrine origin and derive from a primitive stem cell. (From Stedman, 25th ed & Holland et al., Cancer Medicine, 3d ed, p1182)
  • Carcinoid, Goblet Cell [M0003422]
  • Carcinoma [M0003424]
    A malignant neoplasm made up of epithelial cells tending to infiltrate the surrounding tissues and give rise to metastases. It is a histological type of neoplasm but is often wrongly used as a synonym for "cancer." (From Dorland, 27th ed)
  • Carcinoma 256, Walker [M0003430]
    A transplantable carcinoma of the rat that originally appeared spontaneously in the mammary gland of a pregnant albino rat, and which now resembles a carcinoma in young transplants and a sarcoma in older transplants. (Stedman, 25th ed)
  • Carcinoma in Situ [M0003429]
    A lesion with cytological characteristics associated with invasive carcinoma but the tumor cells are confined to the epithelium of origin, without invasion of the basement membrane.
  • Carcinoma of Endocrine Gland [M0332364]
  • Carcinoma, Acinar Cell [M0027495]
    A malignant tumor arising from secreting cells of a racemose gland, particularly the salivary glands. Racemose (Latin racemosus, full of clusters) refers, as does acinar (Latin acinus, grape), to small saclike dilatations in various glands. Acinar cell carcinomas are usually well differentiated and account for about 13% of the cancers arising in the parotid gland. Lymph node metastasis occurs in about 16% of cases. Local recurrences and distant metastases many years after treatment are common. This tumor appears in all age groups and is most common in women. (Stedman, 25th ed; Holland et al., Cancer Medicine, 3d ed, p1240; from DeVita Jr et al., Cancer: Principles & Practice of Oncology, 3d ed, p575)
  • Carcinoma, Adenoid Cystic [M0005497]
    Carcinoma characterized by bands or cylinders of hyalinized or mucinous stroma separating or surrounded by nests or cords of small epithelial cells. When the cylinders occur within masses of epithelial cells, they give the tissue a perforated, sievelike, or cribriform appearance. Such tumors occur in the mammary glands, the mucous glands of the upper and lower respiratory tract, and the salivary glands. They are malignant but slow-growing, and tend to spread locally via the nerves. (Dorland, 27th ed)
  • Carcinoma, Adenosquamous [M0027425]
    A mixed adenocarcinoma and squamous cell or epidermoid carcinoma.
  • Carcinoma, Anaplastic [M0003425]
  • Carcinoma, Basal Cell [M0003431]
    A malignant skin neoplasm that seldom metastasizes but has potentialities for local invasion and destruction. Clinically it is divided into types: nodular, cicatricial, morphaic, and erythematoid (pagetoid). More than 95% of these carcinomas occur in patients over 40. They develop on hair-bearing skin, most commonly on sun-exposed areas. Approximately 85% are found on the head and neck area and the remaining 15% on the trunk and limbs. (From Dorland, 27th ed; DeVita Jr et al., Cancer: Principles & Practice of Oncology, 3d ed, p1471)
  • Carcinoma, Basosquamous [M0003432]
    A skin carcinoma that histologically exhibits both basal and squamous elements. (From Dorland, 27th ed)
  • Carcinoma, Bronchogenic [M0003434]
    A cancer of the lung, so-called because it arises from the epithelium of the bronchial tree. It is not a histologic designation despite the name.
  • Carcinoma, Brown-Pearce [M0003435]
  • Carcinoma, Cribriform [M0000358]
  • Carcinoma, Ductal [M0445446]
    Malignant neoplasms involving the ductal systems of any of a number of organs, such as the MAMMARY GLANDS, the PANCREAS, the PROSTATE, or the LACRIMAL GLAND.
  • Carcinoma, Ductal, Breast [M0027498]
    An invasive (infiltrating) CARCINOMA of the mammary ductal system (MAMMARY GLANDS) in the human BREAST.
  • Carcinoma, Ehrlich Tumor [M0003437]
    A transplantable, poorly differentiated malignant tumor which appeared originally as a spontaneous breast carcinoma in a mouse. It grows in both solid and ascitic forms.
  • Carcinoma, Embryonal [M0027465]
    A highly malignant, primitive form of carcinoma, probably of germinal cell or teratomatous derivation, usually arising in a gonad and rarely in other sites. It is rare in the female ovary, but in the male it accounts for 20% of all testicular tumors. (From Dorland, 27th ed & Holland et al., Cancer Medicine, 3d ed, p1595)
  • Carcinoma, Endometrioid [M0027497]
    An adenocarcinoma characterized by the presence of cells resembling the glandular cells of the ENDOMETRIUM. It is a common histological type of ovarian CARCINOMA and ENDOMETRIAL CARCINOMA. There is a high frequency of co-occurrence of this form of adenocarcinoma in both tissues.
  • Carcinoma, Giant Cell [M0027517]
    An epithelial neoplasm characterized by unusually large anaplastic cells. It is highly malignant with fulminant clinical course, bizarre histologic appearance and poor prognosis. It is most common in the lung and thyroid. (From Stedman, 25th ed & Segen, Dictionary of Modern Medicine, 1992)
  • Carcinoma, Granular Cell [M0000359]
  • Carcinoma, Hepatocellular [M0010236]
    A primary malignant neoplasm of epithelial liver cells. It ranges from a well-differentiated tumor with EPITHELIAL CELLS indistinguishable from normal HEPATOCYTES to a poorly differentiated neoplasm. The cells may be uniform or markedly pleomorphic, or form GIANT CELLS. Several classification schemes have been suggested.
  • Carcinoma, Intraductal, Noninfiltrating [M0003436]
    A noninvasive (noninfiltrating) carcinoma of the breast characterized by a proliferation of malignant epithelial cells confined to the mammary ducts or lobules, without light-microscopy evidence of invasion through the basement membrane into the surrounding stroma.
  • Carcinoma, Islet Cell [M0027504]
    A primary malignant neoplasm of the pancreatic ISLET CELLS. Usually it involves the non-INSULIN-producing cell types, the PANCREATIC ALPHA CELLS and the pancreatic delta cells (SOMATOSTATIN-SECRETING CELLS) in GLUCAGONOMA and SOMATOSTATINOMA, respectively.
  • Carcinoma, Krebs 2 [M0003438]
  • Carcinoma, Large Cell [M0027518]
    A tumor of undifferentiated (anaplastic) cells of large size. It is usually bronchogenic. (From Dorland, 27th ed)
  • Carcinoma, Lewis Lung [M0028181]
    A carcinoma discovered by Dr. Margaret R. Lewis of the Wistar Institute in 1951. This tumor originated spontaneously as a carcinoma of the lung of a C57BL mouse. The tumor does not appear to be grossly hemorrhagic and the majority of the tumor tissue is a semifirm homogeneous mass. (From Cancer Chemother Rep 2 1972 Nov;(3)1:325) It is also called 3LL and LLC and is used as a transplantable malignancy.
  • Carcinoma, Lobular [M0027506]
    A infiltrating (invasive) breast cancer, relatively uncommon, accounting for only 5%-10% of breast tumors in most series. It is often an area of ill-defined thickening in the breast, in contrast to the dominant lump characteristic of ductal carcinoma. It is typically composed of small cells in a linear arrangement with a tendency to grow around ducts and lobules. There is likelihood of axillary nodal involvement with metastasis to meningeal and serosal surfaces. (DeVita Jr et al., Cancer: Principles & Practice of Oncology, 3d ed, p1205)
  • Carcinoma, Mammary Ductal [M0445599]
  • Carcinoma, Medullary [M0027507]
    A carcinoma composed mainly of epithelial elements with little or no stroma. Medullary carcinomas of the breast constitute 5%-7% of all mammary carcinomas; medullary carcinomas of the thyroid comprise 3%-10% of all thyroid malignancies. (From Dorland, 27th ed; DeVita Jr et al., Cancer: Principles & Practice of Oncology, 3d ed, p1141; Segen, Dictionary of Modern Medicine, 1992)
  • Carcinoma, Merkel Cell [M0023505]
    A carcinoma arising from MERKEL CELLS located in the basal layer of the epidermis and occurring most commonly as a primary neuroendocrine carcinoma of the skin. Merkel cells are tactile cells of neuroectodermal origin and histologically show neurosecretory granules. The skin of the head and neck are a common site of Merkel cell carcinoma, occurring generally in elderly patients. (Holland et al., Cancer Medicine, 3d ed, p1245)
  • Carcinoma, Mucoepidermoid [M0027508]
    A tumor of both low- and high-grade malignancy. The low-grade grow slowly, appear in any age group, and are readily cured by excision. The high-grade behave aggressively, widely infiltrate the salivary gland and produce lymph node and distant metastases. Mucoepidermoid carcinomas account for about 21% of the malignant tumors of the parotid gland and 10% of the sublingual gland. They are the most common malignant tumor of the parotid. (From DeVita Jr et al., Cancer: Principles & Practice of Oncology, 3d ed, p575; Holland et al., Cancer Medicine, 3d ed, p1240)
  • Carcinoma, Neuroendocrine [M0027509]
    A group of carcinomas which share a characteristic morphology, often being composed of clusters and trabecular sheets of round "blue cells", granular chromatin, and an attenuated rim of poorly demarcated cytoplasm. Neuroendocrine tumors include carcinoids, small ("oat") cell carcinomas, medullary carcinoma of the thyroid, Merkel cell tumor, cutaneous neuroendocrine carcinoma, pancreatic islet cell tumors, and pheochromocytoma. Neurosecretory granules are found within the tumor cells. (Segen, Dictionary of Modern Medicine, 1992)
  • Carcinoma, Non-Small-Cell Lung [M0003440]
    A heterogeneous aggregate of at least three distinct histological types of lung cancer, including SQUAMOUS CELL CARCINOMA; ADENOCARCINOMA; and LARGE CELL CARCINOMA. They are dealt with collectively because of the shared properties of poor response to conventional chemotherapy and the potential for cure with surgical resection in a fraction of patients.
  • Carcinoma, Oat Cell [M0027520]
  • Carcinoma, Pancreatic Ductal [M0352972]
    Carcinoma that arises from the PANCREATIC DUCTS. It accounts for the majority of cancers derived from the PANCREAS.
  • Carcinoma, Papillary [M0003441]
    A malignant neoplasm characterized by the formation of numerous, irregular, finger-like projections of fibrous stroma that is covered with a surface layer of neoplastic epithelial cells. (Stedman, 25th ed)
  • Carcinoma, Papillary, Follicular [M0027493]
    A thyroid neoplasm of mixed papillary and follicular arrangement. Its biological behavior and prognosis is the same as that of a papillary adenocarcinoma of the thyroid. (From DeVita Jr et al., Cancer: Principles & Practice of Oncology, 3d ed, p1271)
  • Carcinoma, Renal Cell [M0003442]
    A heterogeneous group of sporadic or hereditary carcinoma derived from cells of the KIDNEYS. There are several subtypes including the clear cells, the papillary, the chromophobe, the collecting duct, the spindle cells (sarcomatoid), or mixed cell-type carcinoma.
  • Carcinoma, Signet Ring Cell [M0027510]
    A poorly differentiated adenocarcinoma in which the nucleus is pressed to one side by a cytoplasmic droplet of mucus. It usually arises in the gastrointestinal system.
  • Carcinoma, Skin Appendage [M0027511]
    A malignant tumor of the skin appendages, which include the hair, nails, sebaceous glands, sweat glands, and the mammary glands. (From Dorland, 27th ed)
  • Carcinoma, Small Cell [M0027519]
    An anaplastic, highly malignant, and usually bronchogenic carcinoma composed of small ovoid cells with scanty neoplasm. It is characterized by a dominant, deeply basophilic nucleus, and absent or indistinct nucleoli. There are admixtures of small cell lung carcinoma with other types of lung cancer. Small cell carcinomas are distinguished by their distinctive biological features, response to chemotherapy and radiotherapy, and by their nearly universal tendency to develop overt or subclinical metastases, which frequently eliminates surgery in most patients. (From Stedman, 25th ed; Holland et al., Cancer Medicine, 3d ed, p1286-7)
  • Carcinoma, Spindle-Cell [M0003426]
  • Carcinoma, Squamous Cell [M0003444]
    A carcinoma derived from stratified squamous epithelium. It may also occur in sites where glandular or columnar epithelium is normally present. (From Stedman, 25th ed)
  • Carcinoma, Thymic [M0021460]
  • Carcinoma, Transitional Cell [M0003445]
    A malignant neoplasm derived from transitional epithelium, occurring chiefly in the urinary bladder, ureters or renal pelves (especially if well differentiated), frequently papillary. Transitional cell carcinomas are graded 1 to 3 or 4 according to the degree of anaplasia, grade 1 appearing histologically benign but being liable to recurrence. (Stedman, 25th ed)
  • Carcinoma, Undifferentiated [M0003427]
  • Carcinoma, Verrucous [M0027522]
    A variant of well-differentiated epidermoid carcinoma that is most common in the oral cavity, but also occurs in the larynx, nasal cavity, esophagus, penis, anorectal region, vulva, vagina, uterine cervix, and skin, especially on the sole of the foot. Most intraoral cases occur in elderly male abusers of smokeless tobacco. The treatment is surgical resection. Radiotherapy is not indicated, as up to 30% treated with radiation become highly aggressive within six months. (Segen, Dictionary of Modern Medicine, 1992)
  • Carcinomatosis [M0003428]
  • Carcinosarcoma [M0003446]
    A malignant neoplasm that contains elements of carcinoma and sarcoma so extensively intermixed as to indicate neoplasia of epithelial and mesenchymal tissue. (Stedman, 25th ed)
  • Carotid Body Tumor [M0003547]
    An invariably benign, encapsulated, firm round mass at the bifurcation of the common carotid artery, with nests of large polyhedral cells in alveolar or organoid arrangement. It is usually asymptomatic but large masses may encroach upon the parapharyngeal space and produce dysphagia, pain, and cranial nerve palsies. (Dorland, 27th ed; DeVita Jr et al., Cancer: Principles & Practice of Oncology, 3d ed, pp570-71)
  • Cecal Neoplasms [M0003709]
    Tumors or cancer of the CECUM.
  • Cell Transformation, Neoplastic [M0003771]
    Cell changes manifested by escape from control mechanisms, increased growth potential, alterations in the cell surface, karyotypic abnormalities, morphological and biochemical deviations from the norm, and other attributes conferring the ability to invade, metastasize, and kill.
  • Cellular Blue Nevus [M0464108]
  • Cementoma [M0003796]
    An odontogenic fibroma in which cells have developed into cementoblasts and which consists largely of cementum.
  • Central Nervous System Cysts [M0328216]
    Congenital or acquired cysts of the brain, spinal cord, or meninges which may remain stable in size or undergo progressive enlargement.
  • Central Nervous System Neoplasms [M0025244]
    Benign and malignant neoplastic processes that arise from or secondarily involve the brain, spinal cord, or meninges.
  • Central Nervous System Neoplasms, Primary [M0337051]
  • Cerebellar Cancer [M0334442]
  • Cerebellar Neoplasms [M0003860]
    Primary or metastatic neoplasms of the CEREBELLUM. Tumors in this location frequently present with ATAXIA or signs of INTRACRANIAL HYPERTENSION due to obstruction of the fourth ventricle. Common primary cerebellar tumors include fibrillary ASTROCYTOMA and cerebellar HEMANGIOBLASTOMA. The cerebellum is a relatively common site for tumor metastases from the lung, breast, and other distant organs. (From Okazaki & Scheithauer, Atlas of Neuropathology, 1988, p86 and p141)
  • Cerebellar Neoplasms, Primary [M0334444]
  • Cerebellopontine Angle Acoustic Neuroma [M0335874]
  • Cerebral Astrocytoma [M0336537]
  • Cerebral Convexity Meningioma [M0337829]
  • Cerebral Primitive Neuroectodermal Tumor [M0337492]
  • Cerebral Ventricle Neoplasms [M0003902]
    Neoplasms located in the brain ventricles, including the two lateral, the third, and the fourth ventricle. Ventricular tumors may be primary (e.g., CHOROID PLEXUS NEOPLASMS and GLIOMA, SUBEPENDYMAL), metastasize from distant organs, or occur as extensions of locally invasive tumors from adjacent brain structures.
  • Cervical Intraepithelial Neoplasia [M0027524]
    A malignancy arising in uterine cervical epithelium and confined thereto, representing a continuum of histological changes ranging from well-differentiated CIN 1 (formerly, mild dysplasia) to severe dysplasia/carcinoma in situ, CIN 3. The lesion arises at the squamocolumnar cell junction at the transformation zone of the endocervical canal, with a variable tendency to develop invasive epidermoid carcinoma, a tendency that is enhanced by concomitant human papillomaviral infection. (Segen, Dictionary of Modern Medicine, 1992)
  • Cervical Intraepithelial Neoplasia, Grade III [M0027523]
  • Childhood Cerebral Astrocytoma [M0336538]
  • Childhood Optic Nerve Glioma [M0335900]
  • Cholangiocarcinoma [M0027512]
    A malignant tumor arising from the intrahepatic bile duct epithelium. It is composed of ducts lined by cuboidal or columnar cells that do not contain bile, with abundant stroma. (From Holland et al., Cancer Medicine, 3d ed, p1455; Stedman, 25th ed)
  • Chondroblastoma [M0004304]
    A usually benign tumor composed of cells which arise from chondroblasts or their precursors and which tend to differentiate into cartilage cells. It occurs primarily in the epiphyses of adolescents. It is relatively rare and represents less than 2% of all primary bone tumors. The peak incidence is in the second decade of life; it is about twice as common in males as in females. (From Dorland, 27th ed; Holland et al., Cancer Medicine, 3d ed, p1846)
  • Chondroma [M0004327]
    A benign neoplasm derived from mesodermal cells that form cartilage. It may remain within the substance of a cartilage or bone (true chondroma or enchondroma) or may develop on the surface of a cartilage (ecchondroma or ecchondrosis). (Dorland, 27th ed; Stedman, 25th ed)
  • Chondromatosis [M0027439]
    Multiple formation of chondromas. (Dorland, 27th ed)
  • Chondrosarcoma [M0004329]
    A slowly growing malignant neoplasm derived from cartilage cells, occurring most frequently in pelvic bones or near the ends of long bones, in middle-aged and old people. Most chondrosarcomas arise de novo, but some may develop in a preexisting benign cartilaginous lesion or in patients with ENCHONDROMATOSIS. (Stedman, 25th ed)
  • Chondrosarcoma, Mesenchymal [M0027440]
    A rare aggressive variant of chondrosarcoma, characterized by a biphasic histologic pattern of small compact cells intermixed with islands of cartilaginous matrix. Mesenchymal chondrosarcomas have a predilection for flat bones; long tubular bones are rarely affected. They tend to occur in the younger age group and are highly metastatic. (DeVita Jr et al., Cancer: Principles & Practice of Oncology, 3d ed, p1456)
  • Chordoma [M0004333]
    A malignant tumor arising from the embryonic remains of the notochord. It is also called chordocarcinoma, chordoepithelioma, and notochordoma. (Dorland, 27th ed)
  • Chorioangioma [M0461746]
  • Choriocarcinoma [M0004339]
    A malignant metastatic form of trophoblastic tumors. Unlike the HYDATIDIFORM MOLE, choriocarcinoma contains no CHORIONIC VILLI but rather sheets of undifferentiated cytotrophoblasts and syncytiotrophoblasts (TROPHOBLASTS). It is characterized by the large amounts of CHORIONIC GONADOTROPIN produced. Tissue origins can be determined by DNA analyses: placental (fetal) origin or non-placental origin (CHORIOCARCINOMA, NON-GESTATIONAL).
  • Choriocarcinoma, Non-gestational [M0399102]
    A highly malignant CHORIOCARCINOMA derived from the non-placental origin such as the totipotent cells in the TESTIS, the OVARY, and the PINEAL GLAND. It produces high levels of CHORIONIC GONADOTROPIN and can metastasize widely through the bloodstream to the lungs, brain, liver, bone, and other viscera by the time of diagnosis.
  • Choroid Neoplasms [M0004347]
    Tumors of the choroid; most common intraocular tumors are malignant melanomas of the choroid. These usually occur after puberty and increase in incidence with advancing age. Most malignant melanomas of the uveal tract develop from benign melanomas (nevi).
  • Choroid Plexus Neoplasms [M0025246]
    Benign or malignant tumors which arise from the choroid plexus of the ventricles of the brain. Papillomas (see PAPILLOMA, CHOROID PLEXUS) and carcinomas are the most common histologic subtypes, and tend to seed throughout the ventricular and subarachnoid spaces. Clinical features include headaches, ataxia and alterations of consciousness, primarily resulting from associated HYDROCEPHALUS. (From Devita et al., Cancer: Principles and Practice of Oncology, 5th ed, p2072; J Neurosurg 1998 Mar;88(3):521-8)
  • Choroid Plexus Neoplasms, Primary [M0334649]
  • Chromophobe Renal Cell Carcinoma [M0483487]
  • Clear Cell Meningioma [M0337830]
  • Clear Cell Renal Cell Carcinoma [M0483485]
  • Cocarcinogenesis [M0004672]
    The combination of two or more different factors in the production of cancer.
  • Collecting Duct Carcinoma (Kidney) [M0483488]
  • Colonic Neoplasms [M0004817]
    Tumors or cancer of the COLON.
  • Colorectal Cancer [M0023327]
  • Colorectal Carcinoma [M0023328]
  • Colorectal Neoplasms [M0023329]
    Tumors or cancer of the COLON or the RECTUM or both. Risk factors for colorectal cancer include chronic ULCERATIVE COLITIS; FAMILIAL POLYPOSIS COLI; exposure to ASBESTOS; and irradiation of the CERVIX UTERI.
  • Colorectal Neoplasms, Hereditary Nonpolyposis [M0004834]
    A group of autosomal-dominant inherited diseases in which COLON CANCER arises in discrete adenomas. Unlike FAMILIAL POLYPOSIS COLI with hundreds of polyps, hereditary nonpolyposis colorectal neoplasms occur much later, in the fourth and fifth decades. HNPCC has been associated with germline mutations in mismatch repair (MMR) genes.
  • Common Bile Duct Neoplasms [M0004863]
    Tumor or cancer of the COMMON BILE DUCT including the AMPULLA OF VATER and the SPHINCTER OF ODDI.
  • Condition, Preneoplastic [M0017449]
  • Congenital Epulides [M0009241]
  • Conjunctival Neoplasms [M0005014]
    Tumors or cancer of the CONJUNCTIVA.
  • Conn Adenoma [M0010807]
  • Cranial Nerve Neoplasms [M0005280]
    Benign and malignant neoplasms that arise from one or more of the twelve cranial nerves.
  • Cranial Nerve Neoplasms, Malignant [M0335872]
  • Cranial Neuroma, Benign [M0335870]
  • Craniopharyngioma [M0005287]
    A benign pituitary-region neoplasm that originates from Rathke's pouch. The two major histologic and clinical subtypes are adamantinous (or classical) craniopharyngioma and papillary craniopharyngioma. The adamantinous form presents in children and adolescents as an expanding cystic lesion in the pituitary region. The cystic cavity is filled with a black viscous substance and histologically the tumor is composed of adamantinomatous epithelium and areas of calcification and necrosis. Papillary craniopharyngiomas occur in adults, and histologically feature a squamous epithelium with papillations. (From Joynt, Clinical Neurology, 1998, Ch14, p50)
  • Craniopharyngioma, Adamantinous [M0337313]
  • Craniopharyngioma, Adult [M0337315]
  • Craniopharyngioma, Child [M0337316]
  • Craniopharyngioma, Papillary [M0337314]
  • Cystadenocarcinoma [M0005526]
    A malignant neoplasm derived from glandular epithelium, in which cystic accumulations of retained secretions are formed. The neoplastic cells manifest varying degrees of anaplasia and invasiveness, and local extension and metastases occur. Cystadenocarcinomas develop frequently in the ovaries, where pseudomucinous and serous types are recognized. (Stedman, 25th ed)
  • Cystadenocarcinoma, Mucinous [M0027513]
    A malignant cystic or semisolid tumor most often occurring in the ovary. Rarely, one is solid. This tumor may develop from a mucinous cystadenoma, or it may be malignant at the onset. The cysts are lined with tall columnar epithelial cells; in others, the epithelium consists of many layers of cells that have lost normal structure entirely. In the more undifferentiated tumors, one may see sheets and nests of tumor cells that have very little resemblance to the parent structure. (Hughes, Obstetric-Gynecologic Terminology, 1972, p184)
  • Cystadenocarcinoma, Papillary [M0027514]
    An adenocarcinoma in which the tumor elements are arranged as finger-like processes or as a solid spherical nodule projecting from an epithelial surface.
  • Cystadenocarcinoma, Serous [M0027515]
    A malignant cystic or semicystic neoplasm. It often occurs in the ovary and usually bilaterally. The external surface is usually covered with papillary excrescences. Microscopically, the papillary patterns are predominantly epithelial overgrowths with differentiated and undifferentiated papillary serous cystadenocarcinoma cells. Psammoma bodies may be present. The tumor generally adheres to surrounding structures and produces ascites. (From Hughes, Obstetric-Gynecologic Terminology, 1972, p185)
  • Cystadenoma [M0005527]
    A benign neoplasm derived from glandular epithelium, in which cystic accumulations of retained secretions are formed. In some instances, considerable portions of the neoplasm, or even the entire mass, may be cystic. (Stedman, 25th ed)
  • Cystadenoma, Mucinous [M0027525]
    A multilocular tumor with mucin secreting epithelium. They are most often found in the ovary, but are also found in the pancreas, appendix, and rarely, retroperitoneal and in the urinary bladder. They are considered to have low-grade malignant potential.
  • Cystadenoma, Papillary [M0027526]
    A benign neoplasm of the ovary.
  • Cystadenoma, Serous [M0027527]
    A cystic tumor of the ovary, containing thin, clear, yellow serous fluid and varying amounts of solid tissue, with a malignant potential several times greater than that of mucinous cystadenoma (CYSTADENOMA, MUCINOUS). It can be unilocular, parvilocular, or multilocular. It is often bilateral and papillary. The cysts may vary greatly in size. (Dorland, 27th ed; from Hughes, Obstetric-Gynecologic Terminology, 1972)
  • Denys-Drash Syndrome [M0376570]
    A rare syndrome characterized by UROGENITAL ABNORMALITIES; GONADAL DYSGENESIS; PSEUDOHERMAPHRODITISM; and WILMS TUMOR. It is caused by a mutation in the Wilms tumor suppressor gene (GENES, WILMS TUMOR) on chromosome 11.
  • Dermatofibroma [M0001195]
    A slowly growing benign skin nodule consisting of poorly demarcated cellular fibrous tissue enclosing collapsed CAPILLARIES with scattered HEMOSIDERIN-pigmented and lipid MACROPHAGES. They are common, usually about 1 cm in diameter and occur in the DERMIS. (From Stedman, 25th ed; DeVita Jr et al., Cancer: Principles & Practice of Oncology, 3d ed, p1356)
  • Dermatofibrosarcoma [M0027452]
    A fibrosarcoma of the skin, beginning most often as an indurated nodule that grows slowly and hence is often ignored until it grows large. Dermatofibrosarcomas show an extremely aggressive tendency to invade local surrounding tissue. They do not metastasize, however, even after multiple recurrences. About 50% will recur after simple incision; hence wide excision should be resorted to. (DeVita Jr et al., Cancer: Principles & Practice of Oncology, 3d ed, p1356)
  • Dermoid Cyst [M0006065]
    A tumor consisting of displaced ectodermal structures along the lines of embryonic fusion, the wall being formed of epithelium-lined connective tissue, including skin appendages, and containing keratin, sebum, and hair. (Stedman, 25th ed)
  • Digestive System Neoplasms [M0006375]
    Tumors or cancer of the DIGESTIVE SYSTEM.
  • Distorted Hearing [M0336587]
  • Duodenal Cancer [M0445961]
  • Duodenal Neoplasms [M0006882]
    Tumors or cancer of the DUODENUM.
  • Dysgerminoma [M0006918]
    A malignant ovarian neoplasm, thought to be derived from primordial germ cells of the sexually undifferentiated embryonic gonad. It is the counterpart of the classical seminoma of the testis, to which it is both grossly and histologically identical. Dysgerminomas comprise 16% of all germ cell tumors but are rare before the age of 10, although nearly 50% occur before the age of 20. They are generally considered of low-grade malignancy but may spread if the tumor extends through its capsule and involves lymph nodes or blood vessels. (Dorland, 27th ed; DeVita Jr et al., Cancer: Principles & Practice of Oncology, 3d ed, p1646)
  • Dysplastic Nevi [M0006930]
  • Dysplastic Nevus Syndrome [M0006928]
    Clinically atypical nevi (usually exceeding 5 mm in diameter and having variable pigmentation and ill defined borders) with an increased risk for development of non-familial cutaneous malignant melanoma. Biopsies show melanocytic dysplasia. Nevi are clinically and histologically identical to the precursor lesions for melanoma in the B-K mole syndrome. (Stedman, 25th ed)
  • Ear Neoplasms [M0006942]
    Tumors or cancer of the internal, external, or middle ear.
  • Enchondroma [M0004328]
  • Endocrine Gland Neoplasms [M0007397]
    Tumors or cancer of the ENDOCRINE GLANDS.
  • Endodermal Sinus Tumor [M0027469]
    An unusual and aggressive tumor of germ-cell origin that reproduces the extraembryonic structures of the early embryo. It is the most common malignant germ cell tumor found in children. It is characterized by a labyrinthine glandular pattern of flat epithelial cells and rounded papillary processes with a central capillary (Schiller-Duval body). The tumor is rarely bilateral. Before the use of combination chemotherapy, the tumor was almost invariably fatal. (From DeVita Jr et al., Cancer: Principles & Practice of Oncology, 3d ed, p1189)
  • Endometrial Carcinoma [M0025699]
  • Endometrial Neoplasms [M0025700]
    Tumors or cancer of ENDOMETRIUM, the mucous lining of the UTERUS. These neoplasms can be benign or malignant. Their classification and grading are based on the various cell types and the percent of undifferentiated cells.
  • Endometrial Stromal Tumors [M0407054]
    Neoplasms of the endometrial stroma that sometimes involve the MYOMETRIUM. These tumors contain cells that may closely or remotely resemble the normal stromal cells. Endometrial stromal neoplasms are divided into three categories: (1) benign stromal nodules; (2) low-grade stromal sarcoma, or endolymphatic stromal myosis; and (3) malignant endometrial stromal sarcoma (SARCOMA, ENDOMETRIAL STROMAL).
  • Enzootic Bovine Leukosis [M0025293]
    A lymphoid neoplastic disease in cattle caused by the bovine leukemia virus. Enzootic bovine leukosis may take the form of lymphosarcoma, malignant lymphoma, or leukemia but the presence of malignant cells in the blood is not a consistent finding.
  • Ependymoastrocytoma [M0336847]
  • Ependymoblastoma [M0337489]
  • Ependymoma [M0007536]
    Glioma derived from ependymocytes that tend to present as malignant intracranial tumors in children and as benign intraspinal neoplasms in adults. It may arise from any level of the ventricular system or central canal of the spinal cord. Intracranial ependymomas most frequently originate in the FOURTH VENTRICLE and histologically are densely cellular tumors which may contain ependymal tubules and perivascular pseudorosettes. Spinal ependymomas are usually benign papillary or myxopapillary tumors. (From DeVita et al., Principles and Practice of Oncology, 5th ed, p2018; Escourolle et al., Manual of Basic Neuropathology, 2nd ed, pp28-9)
  • Ependymoma, Myxopapillary [M0009273]
  • Ependymoma, Papillary [M0337465]
  • Epidermodysplasia Verruciformis [M0007556]
    An autosomal recessive trait with impaired cell-mediated immunity. About 15 human papillomaviruses are implicated in associated infection, four of which lead to skin neoplasms. The disease begins in childhood with red papules and later spreads over the body as gray or yellow scales.
  • Epidural Neoplasm, Malignant [M0334935]
  • Epidural Neoplasms [M0023324]
    Neoplasms located in the space between the vertebral PERIOSTEUM and DURA MATER surrounding the SPINAL CORD. Tumors in this location are most often metastatic in origin and may cause neurologic deficits by mass effect on the spinal cord or nerve roots or by interfering with blood supply to the spinal cord.
  • Esophageal Neoplasms [M0007750]
    Tumors or cancer of the ESOPHAGUS.
  • Esthesioneuroblastoma, Olfactory [M0027538]
    A malignant olfactory neuroblastoma arising from the olfactory epithelium of the superior nasal cavity and cribriform plate. It is uncommon (3% of nasal tumors) and rarely is associated with the production of excess hormones (e.g., SIADH, Cushing Syndrome). It has a high propensity for multiple local recurrences and bony metastases. (From Holland et al., Cancer Medicine, 3rd ed, p1245; J Laryngol Otol 1998 Jul;112(7):628-33)
  • Exostoses, Multiple Hereditary [M0008037]
    Hereditary disorder transmitted by an autosomal dominant gene and characterized by multiple exostoses (multiple osteochondromas) near the ends of long bones. The genetic abnormality results in a defect in the osteoclastic activity at the metaphyseal ends of the bone during the remodeling process in childhood or early adolescence. The metaphyses develop benign, bony outgrowths often capped by cartilage. A small number undergo neoplastic transformation.
  • Experimental Hepatoma [M0012656]
  • Eye Neoplasms [M0008094]
    Tumors or cancer of the EYE.
  • Eyelid Neoplasms [M0008106]
    Tumors of cancer of the EYELIDS.
  • Facial Neoplasms [M0008120]
  • Fallopian Tube Cancer [M0482643]
  • Fallopian Tube Neoplasms [M0008173]
    Benign or malignant neoplasms of the FALLOPIAN TUBES. They are uncommon. If they develop, they may be located in the wall or within the lumen as a growth attached to the wall by a stalk.
  • Familial Acoustic Neuromas [M0406511]
  • Familial Atypical Multiple Mole-Melanoma [M0006929]
  • Familial Retinoblastoma [M0336985]
  • Femoral Neoplasms [M0008314]
  • Fibrillary Astrocytoma [M0336539]
  • Fibro-odontoma, Ameloblastic [M0015227]
  • Fibroadenoma [M0027455]
    An adenoma containing fibrous tissue. It should be differentiated from ADENOFIBROMA which is a tumor composed of connective tissue (fibroma) containing glandular (adeno-) structures. (From Dorland, 27th ed)
  • Fibroadenosis [M0000363]
  • Fibroid Uterus [M0012317]
  • Fibroma [M0008445]
    A benign tumor of fibrous or fully developed connective tissue.
  • Fibroma, Desmoplastic [M0027449]
    A extremely rare bone tumor characterized by abundant collagen formation and a fibrous stroma, without evidence of mitosis or pleomorphism. It appears on x-rays as an osteolytic lesion with well-defined margins and must be differentiated from primary fibrosarcoma of bone. (DeVita Jr et al., Cancer: Principles & Practice of Oncology, 3d ed, p1441)
  • Fibroma, Ossifying [M0027443]
    A benign, relatively slow-growing, central bone tumor, usually of the jaws (especially the mandible) which is composed of fibrous connective tissue within which bone is formed. (Dorland, 27th ed)
  • Fibroma, Shope [M0022154]
  • Fibromatosis [M0008446]
  • Fibromatosis, Abdominal [M0027450]
    A relatively large mass of unusually firm scarlike connective tissue resulting from active participation of fibroblasts, occurring most frequently in the abdominal muscles of women who have borne children. The fibroblasts infiltrate surrounding muscle and fascia. (Stedman, 25th ed)
  • Fibromatosis, Aggressive [M0027451]
    A childhood counterpart of abdominal or extra-abdominal desmoid tumors, characterized by firm subcutaneous nodules that grow rapidly in any part of the body but do not metastasize. The adult form of abdominal fibromatosis is FIBROMATOSIS, ABDOMINAL. (Stedman, 25th ed)
  • Fibrosarcoma [M0008451]
    A sarcoma derived from deep fibrous tissue, characterized by bundles of immature proliferating fibroblasts with variable collagen formation, which tends to invade locally and metastasize by the bloodstream. (Stedman, 25th ed)
  • Fibrous Meningioma [M0337831]
  • Gallbladder Neoplasms [M0008959]
    Tumors or cancer of the gallbladder.
  • Gammopathy, Monoclonal [M0408255]
  • Ganglioglioma [M0027537]
    Rare indolent tumors comprised of neoplastic glial and neuronal cells which occur primarily in children and young adults. Benign lesions tend to be associated with long survival unless the tumor degenerates into a histologically malignant form. They tend to occur in the optic nerve and white matter of the brain and spinal cord.
  • Ganglioglioma, Benign [M0337405]
  • Ganglioglioma, Intracranial [M0337407]
  • Ganglioglioma, Malignant [M0337406]
  • Ganglioneuroblastoma [M0027539]
    A moderately malignant neoplasm composed of primitive neuroectodermal cells dispersed in myxomatous or fibrous stroma intermixed with mature ganglion cells. It may undergo transformation into a neuroblastoma. It arises from the sympathetic trunk or less frequently from the adrenal medulla, cerebral cortex, and other locations. Cervical ganglioneuroblastomas may be associated with HORNER SYNDROME and the tumor may occasionally secrete vasoactive intestinal peptide, resulting in chronic diarrhea.
  • Ganglioneuroma [M0008984]
    A benign neoplasm that usually arises from the sympathetic trunk in the mediastinum. Histologic features include spindle cell proliferation (resembling a neurofibroma) and the presence of large ganglion cells. The tumor may present clinically with HORNER SYNDROME or diarrhea due to ectopic production of vasoactive intestinal peptide. (From DeVita et al., Cancer: Principles and Practice of Oncology, 5th ed, p966)
  • Gardner Syndrome [M0008991]
    A variant of ADENOMATOUS POLYPOSIS COLI caused by mutation in the APC gene (GENES, APC) on CHROMOSOME 5. It is characterized by not only the presence of multiple colonic polyposis but also extracolonic ADENOMATOUS POLYPS in the UPPER GASTROINTESTINAL TRACT; the EYE; the SKIN; the SKULL; and the FACIAL BONES; as well as malignancy in organs other than the GI tract.
  • Gastrinoma [M0023742]
    A GASTRIN-secreting neuroendocrine tumor of the non-beta ISLET CELLS, the GASTRIN-SECRETING CELLS. This type of tumor is primarily located in the PANCREAS or the DUODENUM. Majority of gastrinomas are malignant. They metastasize to the LIVER; LYMPH NODES; and BONE but rarely elsewhere. The presence of gastrinoma is one of three requirements to be met for identification of ZOLLINGER-ELLISON SYNDROME, which sometimes occurs in families with MULTIPLE ENDOCRINE NEOPLASIA TYPE 1; (MEN 1).
  • Gastrointestinal Neoplasms [M0009038]
    Tumors or cancer of the GASTROINTESTINAL TRACT, from the MOUTH to the ANAL CANAL.
  • Gastrointestinal Stromal Tumors [M0452911]
    All tumors in the GASTROINTESTINAL TRACT arising from mesenchymal cells (MESODERM) except those of smooth muscle cells (LEIOMYOMA) or Schwann cells (SCHWANNOMA).
  • Gemistocytic Astrocytoma [M0336540]
  • Genital Neoplasms, Female [M0009156]
    Tumor or cancer of the female reproductive tract (GENITALIA, FEMALE).
  • Genital Neoplasms, Male [M0009157]
    Tumor or cancer of the MALE GENITALIA.
  • Genitourinary Cancer [M0333641]
  • Germ Cell Cancer [M0333128]
  • Germinoma [M0027466]
    A malignant neoplasm of the germinal tissue of the GONADS; MEDIASTINUM; or pineal region. Germinomas are uniform in appearance, consisting of large, round cells with vesicular nuclei and clear or finely granular eosinophilic-staining cytoplasm. (Stedman, 265th ed; from DeVita Jr et al., Cancer: Principles & Practice of Oncology, 3d ed, pp1642-3)
  • Gestational Trophoblastic Neoplasms [M0398989]
    A group of interrelated trophoblastic diseases arising from pregnancy. They are commonly associated with hyperplasia of trophoblasts (TROPHOBLAST) and markedly elevated human CHORIONIC GONADOTROPIN. They include HYDATIDIFORM MOLE, invasive mole (HYDATIDIFORM MOLE, INVASIVE), placental-site trophoblastic tumor (TROPHOBLASTIC TUMOR, PLACENTAL SITE), and CHORIOCARCINOMA. These neoplasms have varying propensities for invasion and spread.
  • Giant Cell Glioblastoma [M0337425]
  • Giant Cell Tumor of Bone [M0027441]
    A bone tumor composed of cellular spindle-cell stroma containing scattered multinucleated giant cells resembling osteoclasts. The tumors range from benign to frankly malignant lesions. The tumor occurs most frequently in an end of a long tubular bone in young adults. (From Dorland, 27th ed; Stedman, 25th ed)
  • Giant Cell Tumors [M0009221]
    Tumors of bone tissue or synovial or other soft tissue characterized by the presence of giant cells. The most common are giant cell tumor of tendon sheath and GIANT CELL TUMOR OF BONE.
  • Gingival Neoplasms [M0009240]
  • Glandular Neoplasms [M0014598]
  • Glioblastoma [M0009269]
    A malignant form of astrocytoma histologically characterized by pleomorphism of cells, nuclear atypia, microhemorrhage, and necrosis. They may arise in any region of the central nervous system, with a predilection for the cerebral hemispheres, basal ganglia, and commissural pathways. Clinical presentation most frequently occurs in the fifth or sixth decade of life with focal neurologic signs or seizures.
  • Glioblastoma Multiforme [M0009270]
  • Glioma [M0009271]
    Benign and malignant central nervous system neoplasms derived from glial cells (i.e., astrocytes, oligodendrocytes, and ependymocytes). Astrocytes may give rise to astrocytomas (ASTROCYTOMA) or glioblastoma multiforme (see GLIOBLASTOMA). Oligodendrocytes give rise to oligodendrogliomas (OLIGODENDROGLIOMA) and ependymocytes may undergo transformation to become EPENDYMOMA; CHOROID PLEXUS NEOPLASMS; or colloid cysts of the third ventricle. (From Escourolle et al., Manual of Basic Neuropathology, 2nd ed, p21)
  • Glioma, Subependymal [M0027550]
    Rare, slow-growing, benign intraventricular tumors, often asymptomatic and discovered incidentally. The tumors are classified histologically as ependymomas and demonstrate a proliferation of subependymal fibrillary astrocytes among the ependymal tumor cells. (From Clin Neurol Neurosurg 1997 Feb;99(1):17-22)
  • Gliomatosis Cerebri [M0336848]
  • Gliosarcoma [M0027551]
    Rare mixed tumors of the brain and rarely the spinal cord which contain malignant neuroectodermal (glial) and mesenchymal components, including spindle-shaped fibrosarcoma cells. These tumors are highly aggressive and present primarily in adults as rapidly expanding mass lesions. They may arise in tissue that has been previously irradiated. (From Br J Neurosurg 1995 Apr;9(2):171-8)
  • Glomangioma [M0009297]
  • Glomus Jugulare Tumor [M0009305]
    A paraganglioma involving the glomus jugulare, a microscopic collection of chemoreceptor tissue in the adventitia of the bulb of the jugular vein. It may cause paralysis of the vocal cords, attacks of dizziness, blackouts, and nystagmus. It is not resectable but radiation therapy is effective. It regresses slowly, but permanent control is regularly achieved. (From Dorland, 27th ed; Stedman, 25th ed; DeVita Jr et al., Cancer: Principles & Practice of Oncology, 3d ed, pp1603-4)
  • Glomus Tumor [M0009296]
    A blue-red, extremely painful vascular neoplasm involving a glomeriform arteriovenous anastomosis (glomus body), which may be found anywhere in the skin, most often in the distal portion of the fingers and toes, especially beneath the nail. It is composed of specialized pericytes (sometimes termed glomus cells), usually in single encapsulated nodular masses which may be several millimeters in diameter (From Stedman, 27th ed). CHEMODECTOMA, a tumor of NEURAL CREST origin, is also sometimes called a glomus tumor.
  • Glomus Tympanicum Tumor [M0443252]
    A rare PARAGANGLIOMA involving the GLOMUS TYMPANICUM, a collection of chemoreceptor tissue adjacent to the TYMPANIC CAVITY. It can cause TINNITUS and conductive hearing loss (HEARING LOSS, CONDUCTIVE).
  • Glucagonoma [M0009315]
    An almost always malignant GLUCAGON-secreting tumor derived from the PANCREATIC ALPHA CELLS. It is characterized by a distinctive migratory ERYTHEMA; WEIGHT LOSS; STOMATITIS; GLOSSITIS; DIABETES MELLITUS; hypoaminoacidemia; and normochromic normocytic ANEMIA.
  • Gonadoblastoma [M0027467]
    A complex neoplasm composed of a mixture of gonadal elements, such as large primordial GERM CELLS, immature SERTOLI CELLS or GRANULOSA CELLS of the sex cord, and gonadal stromal cells. Gonadoblastomas are most often associated with abnormal chromosomal karyotype, GONADAL DYSGENESIS, and the presence of a Y CHROMOSOME.
  • Granular Cell Tumor [M0025300]
    Unusual tumor affecting any site of the body, but most often encountered in the head and neck. Considerable debate has surrounded the histogenesis of this neoplasm; however, it is considered to be a myoblastoma of, usually, a benign nature. It affects women more often than men. When it develops beneath the epidermis or mucous membrane, it can lead to proliferation of the squamous cells and mimic squamous cell carcinoma.
  • Granuloma, Hodgkin's [M0010485]
  • Granulomatous Slack Skin [M0025094]
  • Granulosa Cell Cancer [M0482645]
  • Granulosa Cell Tumor [M0009616]
    A neoplasm composed entirely of GRANULOSA CELLS, occurring mostly in the OVARY. In the adult form, it may contain some THECA CELLS. This tumor often produces ESTRADIOL and INHIBIN. The excess estrogen exposure can lead to other malignancies in women and PRECOCIOUS PUBERTY in girls. In rare cases, granulosa cell tumors have been identified in the TESTES.
  • Growth Hormone-Secreting Pituitary Adenoma [M0470976]
    A pituitary tumor that secretes GROWTH HORMONE. In humans, excess HUMAN GROWTH HORMONE leads to ACROMEGALY.
  • Gynandroblastoma [M0027543]
    A sex cord-gonadal stromal tumor, composed of cells of both the OVARY and the TESTIS. It produces both male and female GONADAL STEROID HORMONES.
  • Hamartoma Syndrome, Multiple [M0009775]
    A hereditary disease characterized by multiple ectodermal, mesodermal, and endodermal nevoid and neoplastic anomalies. Papules of the face and oral mucosa are the most characteristic lesion. Other changes occur in the skin, in the thyroid, the breast, the gastrointestinal system, and the nervous system.
  • Head and Neck Neoplasms [M0009818]
    Soft tissue tumors or cancer arising from the mucosal surfaces of the LIP; oral cavity; PHARYNX; LARYNX; and cervical esophagus. Other sites included are the NOSE and PARANASAL SINUSES; SALIVARY GLANDS; THYROID GLAND and PARATHYROID GLANDS; and MELANOMA and non-melanoma skin cancers of the head and neck. (from Holland et al., Cancer Medicine, 4th ed, p1651)
  • Head Neoplasms [M0009819]
  • Heart Neoplasms [M0009959]
  • Hemangioblastic Meningioma [M0337832]
  • Hemangioblastoma [M0027560]
    A benign tumor of the nervous system that may occur sporadically or in association with HIPPEL-LINDAU DISEASE. It accounts for approximately 2% of intracranial tumors, arising most frequently in the cerebellar hemispheres and vermis. Histologically, the tumors are composed of multiple capillary and sinusoidal channels lined with endothelial cells and clusters of lipid-laden pseudoxanthoma cells. Usually solitary, these tumors can be multiple and may also occur in the brain stem, spinal cord, retina, and supratentorial compartment. Cerebellar hemangioblastomas usually present in the third decade with INTRACRANIAL HYPERTENSION, and ataxia. (From DeVita et al., Cancer: Principles and Practice of Oncology, 5th ed, pp2071-2)
  • Hemangioendothelioma [M0010030]
    A neoplasm derived from blood vessels, characterized by numerous prominent endothelial cells that occur singly, in aggregates, and as the lining of congeries of vascular tubes or channels. Hemangioendotheliomas are relatively rare and are of intermediate malignancy (between benign hemangiomas and conventional angiosarcomas). They affect men and women about equally and rarely develop in childhood. (From Stedman, 25th ed; Holland et al., Cancer Medicine, 3d ed, p1866)
  • Hemangioendothelioma, Epithelioid [M0027558]
    A tumor of medium-to-large veins, composed of plump-to-spindled endothelial cells that bulge into vascular spaces in a tombstone-like fashion. These tumors are thought to have "borderline" aggression, where one-third develop local recurrences, but only rarely metastasize. It is unclear whether the epithelioid hemangioendothelioma is truly neoplastic or an exuberant tissue reaction, nor is it clear if this is equivalent to Kimura's disease (see ANGIOLYMPHOID HYPERPLASIA WITH EOSINOPHILIA). (Segen, Dictionary of Modern Medicine, 1992)
  • Hemangioma [M0010031]
    A benign tumor, made up of an overgrowth of BLOOD VESSELS. It is extremely common, occurring mostly in infancy and childhood. It can occur anywhere in the body but is most frequently noticed in the SKIN and SUBCUTANEOUS TISSUE. About 75% are present at birth, and about 60% occur in the head and neck area. (from Stedman, 25th ed; DeVita Jr et al., Cancer: Principles & Practice of Oncology, 3d ed, p1355)
  • Hemangioma, Capillary [M0027559]
    A dull red, firm, dome-shaped hemangioma, sharply demarcated from surrounding skin, usually located on the head and neck, which grows rapidly and generally undergoes regression and involution without scarring. It is caused by proliferation of immature capillary vessels in active stroma, and is usually present at birth or occurs within the first two or three months of life. (Dorland, 27th ed)
  • Hemangioma, Cavernous [M0010034]
    A vascular tumor preponderantly composed of large dilated blood vessels, often containing large amounts of blood, occurring in the skin, subcutaneously, or both, and also in many viscera, particularly the liver, spleen, pancreas, and sometimes the brain. The typical superficial lesions are bright to dark red in color; deep lesions have a blue color. A cavernous hemangioma in the skin extends more deeply than a capillary hemangioma and is less likely to regress spontaneously. (Dorland, 27th ed; from Stedman, 25th ed)
  • Hemangioma, Histiocytoid [M0010032]
  • Hemangioma, Intramuscular [M0010033]
  • Hemangiopericytic Meningioma [M0337833]
  • Hemangiopericytoma [M0010035]
    A tumor composed of spindle cells with a rich vascular network, which apparently arises from pericytes, cells of smooth muscle origin that lie around small vessels. Benign and malignant hemangiopericytomas exist, and the rarity of these lesions has led to considerable confusion in distinguishing between benign and malignant variants. (From Dorland, 27th ed; DeVita Jr et al., Cancer: Principles & Practice of Oncology, 3d ed, p1364)
  • Hemangiosarcoma [M0010036]
    A rare malignant neoplasm characterized by rapidly proliferating, extensively infiltrating, anaplastic cells derived from blood vessels and lining irregular blood-filled or lumpy spaces. (Stedman, 25th ed)
  • Hematologic Neoplasms [M0028786]
    Neoplasms located in the blood and blood-forming tissue (the bone marrow and lymphatic tissue). The commonest forms are the various types of LEUKEMIA, of LYMPHOMA, and of the progressive, life-threatening forms of the MYELODYSPLASTIC SYNDROMES.
  • Hematopoietic Neoplasms [M0028785]
  • Hepatoblastoma [M0027426]
    A malignant neoplasm occurring in young children, primarily in the liver, composed of tissue resembling embryonal or fetal hepatic epithelium, or mixed epithelial and mesenchymal tissues. (Stedman, 25th ed)
  • Hepatoma, Morris [M0012653]
  • Hepatoma, Novikoff [M0012654]
  • Hereditary Nonpolyposis Colorectal Cancer [M0444331]
    HNPCC with no history of associated cancers.
  • Hibernoma [M0012571]
    A rare benign human tumor consisting of BROWN ADIPOCYTES resembling those found in some hibernating animals.
  • Hidrocystoma [M0027480]
    A cystic form of sweat gland adenoma (ADENOMA, SWEAT GLAND). It is produced by the cystic proliferation of apocrine secretory glands. It is not uncommon, occurring in adult life in no particular age group, with males and females equally affected. The commonest site is around the eye, particularly lateral to the outer canthus. It is cured by surgical removal. (Stedman, 25th ed; Rook et al., Textbook of Dermatology, 4th ed, p2410)
  • Histiocytic Disorders, Malignant [M0023965]
    Distinctive neoplastic disorders of histiocytes. Included are acute monocytic leukemias, malignant histiocytosis (HISTIOCYTOSIS, MALIGNANT), and true histiocytic lymphomas.
  • Histiocytoma [M0481306]
  • Histiocytoma, Benign Fibrous [M0027448]
    A benign tumor composed, wholly or in part, of cells with the morphologic characteristics of HISTIOCYTES and with various fibroblastic components. Fibrous histiocytomas can occur anywhere in the body. When they occur in the skin, they are called dermatofibromas or sclerosing hemangiomas. (From DeVita Jr et al., Cancer: Principles & Practice of Oncology, 5th ed, p1747)
  • Histiocytoma, Malignant Fibrous [M0481499]
    The most commonly diagnosed soft tissue sarcoma. It is a neoplasm with a fibrohistiocytic appearance found chiefly in later adult life, with peak incidence in the 7th decade.
  • Histiocytosis, Malignant [M0010407]
    A rare, usually rapidly progressive disorder, characterized by abrupt onset, fever, weight loss, hepato-splenomegaly, pancytopenia, and lymphadenopathy.
  • Hodgkin Disease [M0010484]
    A malignant disease characterized by progressive enlargement of the lymph nodes, spleen, and general lymphoid tissue, and the presence of large, usually multinucleate, cells (REED-STERNBERG CELLS) of unknown origin.
  • Hurthle Cell Tumor [M0368761]
    A subtype of follicular adenoma in the THYROID GLAND. The Hurthle cell tumor is composed predominantly (at least 75%) or entirely of oxyphil cells. Hurthle cell neoplasms can be divided into benign and malignant categories. Malignant Hurthle cell carcinoma usually appear in patients over 60 years of age and are radioresistant.
  • Hutchinson's Melanotic Freckle [M0027562]
    A cellular subtype of malignant melanoma. It is a pigmented lesion composed of melanocytes occurring on sun-exposed skin, usually the face and neck. The melanocytes are commonly multinucleated with a "starburst" appearance. It is considered by many to be the in situ phase of lentigo maligna melanoma.
  • Hydatidiform Mole [M0010673]
    Trophoblastic hyperplasia associated with normal gestation, or molar pregnancy. It is characterized by the swelling of the CHORIONIC VILLI and elevated human CHORIONIC GONADOTROPIN. Hydatidiform moles or molar pregnancy may be categorized as complete or partial based on their gross morphology, histopathology, and karyotype.
  • Hydatidiform Mole, Complete [M0399004]
    Derived from the fertilization of an anuclear ovum by one or sometimes two haploid sperm. Its molar chromosomes derive entirely from the paternal origin. It has no identifiable embryonic or fetal tissue. The chorionic villi have generalized swelling and diffuse trophoblastic hyperplasia. Most complete moles (>90%) have a 46,XX karyotype and the rest 46,XY karyotype.
  • Hydatidiform Mole, Invasive [M0004336]
    A uterine tumor derived from persistent gestational TROPHOBLASTS, most likely after a molar pregnancy (HYDATIDIFORM MOLE). Invasive hyadatiform mole develops in about 15% of patients after evacuation of a complete mole and less frequently after other types of gestation. It may perforate the MYOMETRIUM and erode uterine vessels causing hemorrhage.
  • Hydatidiform Mole, Partial [M0399005]
    Derived from the fertilization of an apparently normal ovum by two sperm. Partial hydatidiform moles are characterized by focal chorionic villi swelling, focal trophoblastic hyperplasia, and identifiable fetal or embryonic tissue. Partial moles generally have a triploid karyotype.
  • Hypopharyngeal Cancer [M0332590]
  • Hypopharyngeal Neoplasms [M0010913]
    Tumors or cancer of the HYPOPHARYNX.
  • Hypothalamic Cancer [M0335326]
  • Hypothalamic Neoplasms [M0010937]
    Benign and malignant tumors of the HYPOTHALAMUS. Pilocytic astrocytomas and hamartomas are relatively frequent histologic types. Neoplasms of the hypothalamus frequently originate from adjacent structures, including the OPTIC CHIASM, optic nerve (see OPTIC NERVE NEOPLASMS), and pituitary gland (see PITUITARY NEOPLASMS). Relatively frequent clinical manifestations include visual loss, developmental delay, macrocephaly, and precocious puberty. (From Devita et al., Cancer: Principles and Practice of Oncology, 5th ed, p2051)
  • Hypothalamic Teratomas [M0335345]
  • Hypothalamic-Chiasmatic Neoplasms [M0335323]
  • Hypothalamic-Pituitary Neoplasms [M0335324]
  • Ileal Neoplasms [M0011024]
    Tumors or cancer in the ILEUM region of the small intestine (INTESTINE, SMALL).
  • Immunoproliferative Small Intestinal Disease [M0011165]
    A condition that is caused by HYPERPLASIA of LYMPHOCYTES in the small intestine (INTESTINE, SMALL) and the mesenteric LYMPH NODES. These lymphocytes produce an anomalous alpha heavy chain protein. Generally, these IPSID patients have either concurrent LYMPHOMA or develop lymphoma within a few years. The disease was first described in the Mediterranean region and is characterized by malabsorption; WEIGHT LOSS; DIARRHEA; and STEATORRHEA.
  • Infratentorial Cancer [M0335408]
  • Infratentorial Neoplasms [M0023346]
    Intracranial tumors originating in the region of the brain inferior to the tentorium cerebelli, which contains the cerebellum, fourth ventricle, cerebellopontine angle, brain stem, and related structures. Primary tumors of this region are more frequent in children, and may present with ATAXIA; CRANIAL NERVE DISEASES; vomiting; HEADACHE; HYDROCEPHALUS; or other signs of neurologic dysfunction. Relatively frequent histologic subtypes include TERATOMA; MEDULLOBLASTOMA; GLIOBLASTOMA; ASTROCYTOMA; EPENDYMOMA; CRANIOPHARYNGIOMA; and choroid plexus papilloma (PAPILLOMA, CHOROID PLEXUS).
  • Insulinoma [M0011444]
    A benign tumor of the PANCREATIC BETA CELLS. Insulinoma secretes excess INSULIN resulting in HYPOGLYCEMIA.
  • Intestinal Neoplasms [M0011574]
    Tumors or cancer of the INTESTINES.
  • Intracranial Arachnoid Cysts [M0336765]
  • Intracranial Astrocytoma [M0336541]
  • Intracranial Meningeal Neoplasms [M0337065]
  • Intracranial Meningioma [M0337834]
  • Intradural-Extramedullary Spinal Cord Neoplasms [M0336093]
  • Intramedullary Spinal Cord Neoplasms [M0336094]
  • Intramedullary Spinal Cord Neoplasms, Primary [M0336104]
  • Intraorbital Meningioma [M0481060]
  • Intraventricular Meningioma [M0481061]
  • Iris Neoplasms [M0024212]
    Tumors of the iris characterized by increased pigmentation of melanocytes. Iris nevi are composed of proliferated melanocytes and are associated with neurofibromatosis and malignant melanoma of the choroid and ciliary body. Malignant melanoma of the iris often originates from preexisting nevi.
  • Islet Cell Tumor [M0011745]
  • Jaw Neoplasms [M0011830]
    Cancers or tumors of the MAXILLA or MANDIBLE unspecified. For neoplasms of the maxilla, MAXILLARY NEOPLASMS is available and of the mandible, MANDIBULAR NEOPLASMS is available.
  • Jejunal Neoplasms [M0011840]
    Tumors or cancer in the JEJUNUM region of the small intestine (INTESTINE, SMALL).
  • Juvenile Pilocytic Astrocytoma [M0336542]
  • Keratosis, Seborrheic [M0026535]
    Benign eccrine poromas that present as multiple oval, brown-to-black plaques, located mostly on the chest and back. The age of onset is usually in the fourth or fifth decade.
  • Kidney Neoplasms [M0012021]
    Tumors or cancers of the KIDNEY.
  • Kienbock Disease [M0015515]
    Osteonecrosis of the lunate.
  • Klatskin's Tumor [M0027516]
    Adenocarcinoma of the common hepatic duct bifurcation. These tumors are generally small, sharply localized, and seldom metastasizing. G. Klatskin's original review of 13 cases was published in 1965. Once thought to be relatively uncommon, tumors of the bifurcation of the bile duct now appear to comprise more than one-half of all bile duct cancers. (From Holland et al., Cancer Medicine, 3d ed, p1457)
  • Koehler Disease [M0015516]
  • Krukenberg Tumor [M0012080]
    Mucocellular carcinoma of the ovary, usually metastatic from the gastrointestinal tract, characterized by areas of mucoid degeneration and the presence of signet-ring-like cells. It accounts for 30%-40% of metastatic cancers to the ovaries and possibly 1%-2% of all malignant ovarian tumors. The lesions may not be discovered until the primary disease is advanced, and most patients die of their disease within a year. In some cases, a primary tumor is not found. (From Dorland, 27th ed; Holland et al., Cancer Medicine, 3d ed, p1685)
  • Laryngeal Neoplasms [M0012231]
    Cancers or tumors of the LARYNX or any of its parts: the GLOTTIS; EPIGLOTTIS; LARYNGEAL CARTILAGES; LARYNGEAL MUSCLES; and VOCAL CORDS.
  • Leiomyoma [M0012316]
    A benign tumor derived from smooth muscle tissue, also known as a fibroid tumor. They rarely occur outside of the UTERUS and the GASTROINTESTINAL TRACT but can occur in the SKIN and SUBCUTANEOUS TISSUE, probably arising from the smooth muscle of small blood vessels in these tissues.
  • Leiomyoma, Epithelioid [M0027459]
    A relatively rare smooth muscle tumor found most frequently in the wall of the gastrointestinal tract, especially in the stomach. It is similar to other smooth muscle tumors but may become very large and hemorrhage and exhibit small cystic areas. Simple excision is almost always curative. (From Dorland, 27th ed; DeVita Jr et al., Cancer: Principles & Practice of Oncology, 3d ed, p1354)
  • Leiomyomatosis [M0027460]
    The state of having multiple leiomyomas throughout the body. (Stedman, 25th ed)
  • Leiomyosarcoma [M0012318]
    A sarcoma containing large spindle cells of smooth muscle. Although it rarely occurs in soft tissue, it is common in the viscera. It is the most common soft tissue sarcoma of the gastrointestinal tract and uterus. The median age of patients is 60 years. (From Dorland, 27th ed; Holland et al., Cancer Medicine, 3d ed, p1865)
  • Leiomyosarcoma, Epithelioid [M0012319]
  • Leiomyosarcoma, Myxoid [M0012320]
  • Leptomeningeal Neoplasms [M0337068]
  • Leukemia [M0012382]
    A progressive, malignant disease of the blood-forming organs, characterized by distorted proliferation and development of leukocytes and their precursors in the blood and bone marrow. It is classified according to degree of cell differentiation as acute or chronic, and according to predominant type of cell involved as myelogenous or lymphocytic. (Dorland, 28th ed)
  • Leukemia L1210 [M0012383]
  • Leukemia L5178 [M0012384]
    An experimental lymphocytic leukemia of mice.
  • Leukemia P388 [M0012385]
    An experimental lymphocytic leukemia originally induced in DBA/2 mice by painting with methylcholanthrene.
  • Leukemia, Aleukemic [M0355323]
    A form of leukemia that occurs without detectable levels of abnormal leukocytes within the blood.
  • Leukemia, B-Cell [M0023806]
  • Leukemia, B-Cell, Acute [M0023807]
  • Leukemia, B-Cell, Chronic [M0023808]
  • Leukemia, Basophilic, Acute [M0023828]
  • Leukemia, CALLA-Positive [M0023810]
    Acute leukemia in which lymphocytes are positive for the common acute lymphoblastic leukemia antigen (CALLA).
  • Leukemia, Eosinophilic, Acute [M0023829]
  • Leukemia, Erythroblastic, Acute [M0007713]
    A myeloproliferative disorder characterized by neoplastic proliferation of erythroblastic and myeloblastic elements with atypical erythroblasts and myeloblasts in the peripheral blood.
  • Leukemia, Experimental [M0012386]
    Leukemia induced experimentally in animals by exposure to leukemogenic agents, such as VIRUSES; RADIATION; or by TRANSPLANTATION of leukemic tissues.
  • Leukemia, Feline [M0025292]
    A neoplastic disease of cats frequently associated with feline leukemia virus infection.
  • Leukemia, Hairy Cell [M0012387]
    A neoplastic disease of the lymphoreticular cells which is considered to be a rare type of chronic leukemia; it is characterized by an insidious onset, splenomegaly, anemia, granulocytopenia, thrombocytopenia, little or no lymphadenopathy, and the presence of "hairy" or "flagellated" cells in the blood and bone marrow.
  • Leukemia, Large Granular Lymphocytic [M0012389]
  • Leukemia, Lymphocytic [M0012388]
    Leukemia associated with hyperplasia and overactivity of the lymphoid tissue. There are increased numbers of circulating malignant lymphocytes and lymphoblasts. (Dorland, 28th ed, p919)
  • Leukemia, Lymphocytic, Acute [M0023805]
    Lymphocytic leukemia where cells show little differentiation. There are three major subgroups (FAB L1, L2, & L3) based on distinguishing characteristics of the blast cells. Adult and childhood forms of the disease show biological differences as well.
  • Leukemia, Lymphocytic, Acute, Adult [M0332541]
  • Leukemia, Lymphocytic, Acute, L1 [M0023811]
  • Leukemia, Lymphocytic, Acute, L2 [M0023812]
  • Leukemia, Lymphocytic, Chronic [M0023819]
  • Leukemia, Mast-Cell [M0012390]
    A form of systemic mastocytosis (MASTOCYTOSIS, SYSTEMIC) characterized by the presence of large numbers of tissue MAST CELLS in the peripheral blood without skin lesions. It is a high-grade LEUKEMIA disease with bone marrow smear of >20% MAST CELLS, multi-organ failure and a short survival.
  • Leukemia, Megakaryocytic, Acute [M0012391]
    Nonlymphocytic leukemia in which 20-30% of the bone marrow or peripheral blood cells are of megakaryocyte lineage. Myelofibrosis or increased bone marrow reticulin is common.
  • Leukemia, Mixed-Cell [M0023813]
  • Leukemia, Monocytic, Acute [M0012392]
  • Leukemia, Monocytic, Chronic [M0023834]
  • Leukemia, Myelocytic, Acute [M0012393]
    Progressive, malignant disease of the myeloid tissue in which the granular, polymorphonuclear leukocytes and their precursors predominate.
  • Leukemia, Myeloid [M0012396]
    Form of leukemia characterized by an uncontrolled proliferation of the myeloid lineage and their precursors in the bone marrow and other sites.
  • Leukemia, Myeloid, Acute, M2 [M0012395]
  • Leukemia, Myeloid, Aggressive-Phase [M0023822]
  • Leukemia, Myeloid, Chronic [M0023821]
  • Leukemia, Myeloid, Chronic-Phase [M0023823]
  • Leukemia, Myeloid, Philadelphia-Negative [M0023825]
  • Leukemia, Myeloid, Philadelphia-Positive [M0023826]
  • Leukemia, Myelomonocytic, Acute [M0023837]
  • Leukemia, Myelomonocytic, Chronic [M0023835]
  • Leukemia, Neutrophilic, Chronic [M0023824]
  • Leukemia, Nonlymphocytic, Acute [M0023827]
    Acute leukemia distinguished from acute lymphocytic leukemia (ALL) by the morphology of the marrow and blood leukemic cells. Cytoplasmic granules are usually present and the nucleus is usually large and irregular. ANLL is more common in adults than ALL and occurs at any age.
  • Leukemia, Null-Cell [M0023814]
  • Leukemia, Plasmacytic [M0012397]
  • Leukemia, Pre-B-Cell [M0023809]
  • Leukemia, Prolymphocytic [M0023820]
  • Leukemia, Promyelocytic, Acute [M0023830]
  • Leukemia, Radiation-Induced [M0012398]
  • Leukemia, Subleukemic [M0012399]
    A form of leukemia that occurs without elevated levels of leukocytes within the blood. Lesions containing abnormal leukocytes can be found within tissues.
  • Leukemia, T-Cell [M0023815]
    A subtype of lymphocytic leukemia classified as acute or chronic depending on the degree of cell differentiation, not the duration of the disease.
  • Leukemia, T-Cell, Acute [M0023816]
  • Leukemia, T-Cell, Chronic [M0023818]
  • Leukemia, T-Cell, HTLV-II-Associated [M0023804]
  • Leukemia-Lymphoma, T-Cell, Acute, HTLV-I-Associated [M0023817]
    Aggressive T-Cell malignancy with adult onset, caused by HUMAN T-LYMPHOTROPIC VIRUS 1. It is endemic in Japan, the Caribbean basin, Southeastern United States, Hawaii, and parts of Central and South America and sub-Saharan Africa.
  • Leukemic Infiltration [M0026176]
    A pathologic change in leukemia in which leukemic cells permeate various organs at any stage of the disease. All types of leukemia show various degrees of infiltration, depending upon the type of leukemia. The degree of infiltration may vary from site to site. The liver and spleen are common sites of infiltration, the greatest appearing in myelocytic leukemia, but infiltration is seen also in the granulocytic and lymphocytic types. The kidney is also a common site and of the gastrointestinal system, the stomach and ileum are commonly involved. In lymphocytic leukemia the skin is often infiltrated. The central nervous system too is a common site.
  • Leukokeratosis, Oral [M0494988]
  • Leukoplakia, Hairy [M0026800]
    Epithelial hyperplasia of the oral mucosa associated with Epstein-Barr virus (HERPESVIRUS 4, HUMAN) and found almost exclusively in persons with HIV infection. The lesion consists of a white patch that is often corrugated or hairy.
  • Leukoplakia, Oral [M0012423]
    A white patch seen on the oral mucosa. It is considered a premalignant condition and is often tobacco-induced. When evidence of Epstein-Barr virus is present, the condition is called hairy leukoplakia (LEUKOPLAKIA, HAIRY).
  • Leydig Cell Tumor [M0012442]
    Gonadal interstitial or stromal cell neoplasm composed of only LEYDIG CELLS. These tumors may produce one or more of the steroid hormones such as ANDROGENS; ESTROGENS; and CORTICOSTEROIDS. Clinical symptoms include testicular swelling, GYNECOMASTIA, sexual precocity in children, or virilization (VIRILISM) in females.
  • Li-Fraumeni Syndrome [M0025667]
    Rare autosomal dominant syndrome characterized by mesenchymal and epithelial neoplasms at multiple sites. MUTATION of the p53 tumor suppressor gene, a component of the DNA DAMAGE response pathway, apparently predisposes family members who inherit it to develop certain cancers. The spectrum of cancers in the syndrome was shown to include, in addition to BREAST CANCER and soft tissue sarcomas (SARCOMA); BRAIN TUMORS; OSTEOSARCOMA; LEUKEMIA; and ADRENOCORTICAL CARCINOMA.
  • Linitis Plastica [M0012529]
    A condition where the stomach wall becomes thickened, rubbery and loses its ability to distend. The stomach assumes a "leather bottle" shape. It is most often seen in adenocarcinoma of the stomach. The term is often used synonymously with diffuse adenocarcinoma of the stomach.
  • Lip Neoplasms [M0012538]
    Tumors or cancer of the LIP.
  • Lipoma [M0012570]
    A benign tumor composed of fat cells (ADIPOCYTES). It can be surrounded by a thin layer of connective tissue (encapsulated), or diffuse without the capsule.
  • Lipoma, Pleomorphic [M0012572]
  • Liposarcoma [M0012597]
    A malignant tumor derived from primitive or embryonal lipoblastic cells. It may be composed of well-differentiated fat cells or may be dedifferentiated: myxoid (LIPOSARCOMA, MYXOID), round-celled, or pleomorphic, usually in association with a rich network of capillaries. Recurrences are common and dedifferentiated liposarcomas metastasize to the lungs or serosal surfaces. (From Dorland, 27th ed; Stedman, 25th ed)
  • Liposarcoma, Dedifferentiated [M0012598]
  • Liposarcoma, Myxoid [M0027437]
    A liposarcoma containing myxomatous tissue. (Dorland, 27th ed)
  • Liposarcoma, Pleomorphic [M0012599]
  • Liver Neoplasms [M0012652]
    Tumors or cancer of the LIVER.
  • Liver Neoplasms, Experimental [M0012655]
    Experimentally induced tumors of the LIVER.
  • Lung Cancer [M0012750]
  • Lung Neoplasms [M0012749]
    Tumors or cancer of the LUNG.
  • Luteoma [M0027546]
    An ovarian neoplasm composed of LUTEAL CELLS derived from luteinized GRANULOSA CELLS and THECA CELLS. Luteomas respond to GONADOTROPINS, and vary in their hormone production (PROGESTERONE; ESTROGENS; or ANDROGENS). During PREGNANCY, a transient type of luteoma may develop due to an exaggerated LUTEINIZATION of the OVARY.
  • Lymphangioendothelioma [M0012786]
  • Lymphangioleiomyomatosis [M0027421]
    A disease characterized by the progressive invasion of SMOOTH MUSCLE CELLS into the LYMPHATIC VESSELS, and the BLOOD VESSELS. The majority of the cases occur in the LUNGS of women of child-bearing age, eventually blocking the flow of air, blood, and lymph. The common symptom is shortness of breath (DYSPNEA).
  • Lymphangioma [M0012787]
    A benign tumor representing a congenital malformation of the lymphatic system and made up of newly formed lymph-containing vascular spaces and channels. Lymphangioendothelioma is a type of lymphangioma in which endothelial cells are the dominant component. (From Dorland, 27th ed)
  • Lymphangioma, Cavernous [M0012788]
  • Lymphangioma, Cystic [M0027420]
    A cystic growth originating from lymphatic tissue. It is usually found in the neck, axilla, or groin.
  • Lymphangiomyoma [M0012789]
    A tumorlike condition characterized by smooth muscle and endothelium proliferation of lymphatic vessels and lymph nodes in the mediastinum and retroperitoneum, also in the lung. It may be manifested by chylous pleural effusion and ascites.
  • Lymphangiosarcoma [M0012790]
    A malignant tumor originating from the endothelial cells of lymphatic vessels. Most lymphangiosarcomas arise in an arm secondary to radical mastectomy but they sometimes complicate idiopathic lymphedema. The lymphedema has usually been present for 6 to 10 years before malignant changes develop. (From Dorland, 27th ed; Holland et al., Cancer Medicine, 3d ed, p1866)
  • Lymphatic Metastasis [M0012795]
    Transfer of a neoplasm from its primary site to lymph nodes or to distant parts of the body by way of the lymphatic system.
  • Lymphatic Vessel Tumors [M0027419]
    Neoplasms composed of lymphoid tissue, a lattice work of reticular tissue the interspaces of which contain lymphocytes. The concept does not refer to neoplasms located in lymphatic vessels.
  • Lymphoma [M0012817]
    A general term for various neoplastic diseases of the lymphoid tissue.
  • Lymphoma, AIDS-Related [M0025167]
    B-cell lymphoid tumors that occur in association with AIDS. Patients often present with an advanced stage of disease and highly malignant subtypes including Burkitt lymphoma, immunoblastic large-cell lymphoma, small non-cleaved-cell lymphoma and diffuse large-cell lymphoma. The tumors are often disseminated in unusual extranodal sites and chromosomal abnormalities are frequently present. It is likely that polyclonal B-cell lymphoproliferation in AIDS is a complex result of EBV infection, HIV antigenic stimulation, and T-cell-dependent HIV activation.
  • Lymphoma, B-Cell [M0025074]
    A group of heterogeneous lymphoid tumors generally expressing one or more B-cell antigens or representing malignant transformations of B-lymphocytes.
  • Lymphoma, Bovine [M0025294]
  • Lymphoma, Convoluted T-Cell [M0025081]
  • Lymphoma, Diffuse [M0025078]
    Malignant lymphoma in which neoplastic cells diffusely infiltrate the entire lymph node without any definite organized pattern. Patients whose lymphomas present a diffuse pattern generally have a more unfavorable survival outlook than those presenting with a follicular or nodular pattern.
  • Lymphoma, Follicular [M0012818]
    Malignant lymphoma in which the lymphomatous cells are clustered into identifiable nodules within the lymph nodes. The nodules resemble to some extent the germinal centers of lymph node follicles and most likely represent neoplastic proliferation of lymph node-derived follicular center B-lymphocytes. This class of lymphoma usually occurs in older persons, is commonly multinodal, and possibly extranodal. Patients whose lymphomas present a follicular or nodular pattern generally have a more indolent course than those presenting with a diffuse pattern.
  • Lymphoma, High-Grade [M0025075]
    One of the three major prognostic groupings for non-Hodgkin lymphomas as proposed in the Working Formulation of the Non-Hodgkin's Lymphoma Pathologic Classification Project sponsored by the National Cancer Institute (1981). Lymphomas falling within this group have a relatively unfavorable survival potential.
  • Lymphoma, Intermediate-Grade [M0025076]
    One of the three major prognostic groupings for non-Hodgkin lymphomas as proposed in the Working Formulation of the Non-Hodgkin's Lymphoma Pathologic Classification Project sponsored by the National Cancer Institute (1981). Lymphomas falling within this group have an intermediate survival potential.
  • Lymphoma, Large-Cell [M0012819]
    The most common aggressive form of non-Hodgkin lymphoma. It occurs in both diffuse and nodular form. The large cells may have cleaved and non-cleaved nuclei.
  • Lymphoma, Large-Cell, Diffuse [M0025086]
    Malignant lymphoma composed of large cells which may be both cleaved and noncleaved. The pattern is predominantly diffuse. Most of these lymphomas represent the malignant counterpart of B-lymphocytes at midstage in the process of differentiation.
  • Lymphoma, Large-Cell, Follicular [M0025087]
    Malignant lymphoma in which the majority of neoplastic cells within the follicles are large cleaved or noncleaved cells. The degree to which the follicular center cells retain their ability to form follicles varies with the state of B-cell transformation.
  • Lymphoma, Large-Cell, Immunoblastic [M0025080]
    Malignant lymphoma characterized by the presence of immunoblasts with uniformly round-to-oval nuclei, one or more prominent nucleoli, and abundant cytoplasm. This class may be subdivided into plasmacytoid and clear-cell types based on cytoplasmic characteristics. A third category, pleomorphous, may be analogous to some of the peripheral T-cell lymphomas (LYMPHOMA, T-CELL, PERIPHERAL) recorded in both the United States and Japan.
  • Lymphoma, Large-Cell, Ki-1 [M0026793]
    A large-cell, non-Hodgkin's, malignant lymphoma with pleomorphic appearance and reactivity with the monoclonal antibody Ki-1. The lymphoma is most often found in the skin and lymph nodes and expresses the Ki-1 (CD30) antigen (ANTIGENS, CD30) on its surface. It is often mistaken for metastatic carcinoma and malignant histiocytosis.
  • Lymphoma, Low-Grade [M0025077]
    One of the three major prognostic groupings for non-Hodgkin lymphomas as proposed in the Working Formulation of the Non-Hodgkin's Lymphoma Pathologic Classification Project sponsored by the National Cancer Institute (1981). Lymphomas falling within this group have a relatively favorable survival potential.
  • Lymphoma, Lymphoblastic [M0025082]
    A high-grade malignant lymphoma composed of a diffuse, relatively uniform proliferation of cells with round or convoluted nuclei and scanty cytoplasm. The cells are cytologically similar to the lymphoblasts seen in acute lymphocytic leukemia, and in some cases, the disease may evolve into a leukemic phase morphologically indistinguishable from acute T-lymphocytic leukemia (LEUKEMIA, T-CELL, ACUTE). Lymphoblastic lymphoma represents approximately one-third of the cases of non-Hodgkin's lymphomas in children and 5% of the cases in adults. It is more prevalent in males.
  • Lymphoma, Lymphoblastic, Convoluted [M0025083]
  • Lymphoma, Lymphoblastic, Nonconvoluted [M0025084]
  • Lymphoma, Mixed-Cell [M0012821]
    Malignant lymphoma characterized by the presence of a mixed population of cells, with the smaller cells resembling lymphocytes and the larger ones histiocytes. It usually presents in a nodular (follicular) pattern, but may evolve into a diffuse pattern. (Dorland, 27th ed)
  • Lymphoma, Mixed-Cell, Diffuse [M0025088]
    A heterogeneous group of intermediate-grade lymphomas of mixed cellular composition. Although they have not been extensively studied, it appears that they are predominantly B-cell diseases.
  • Lymphoma, Mixed-Cell, Follicular [M0025090]
    A low-grade malignant lymphoma of follicular pattern in which there is no clear preponderance of one cell type (small or large) over another. The large cells, cleaved or noncleaved, are often 2-3 times larger in diameter than normal lymphocytes.
  • Lymphoma, Mucosa-Associated Lymphoid Tissue [M0027665]
    Extranodal lymphoma of lymphoid tissue associated with mucosa that is in contact with exogenous antigens. Many of the sites of these lymphomas, such as the stomach, salivary gland, and thyroid, are normally devoid of lymphoid tissue. They acquire MALT tissue as a result of an immunologically mediated disorder.
  • Lymphoma, Non-Hodgkin [M0012822]
    Any of a group of malignant tumors of lymphoid tissue that differ from HODGKIN DISEASE, being more heterogeneous with respect to malignant cell lineage, clinical course, prognosis, and therapy. The only common feature among these tumors is the absence of giant REED-STERNBERG CELLS, a characteristic of Hodgkin's disease.
  • Lymphoma, Small Cleaved-Cell, Diffuse [M0025089]
    An intermediate-grade malignant lymphoma in which the neoplastic cells (B-lymphocytes) exhibit variability in size, configuration, and degree of differentiation. The cells are irregular in shape and have distinct nuclei.
  • Lymphoma, Small Cleaved-Cell, Follicular [M0025091]
    A low-grade malignant lymphoma of predominantly follicular pattern. Follicles are of relatively uniform size and shape and the cells are usually somewhat larger than normal lymphocytes. Nuclei are irregular with prominent indentations and cytoplasm can rarely be identified. Cells exhibiting these characteristics are often called centrocytes.
  • Lymphoma, Small Lymphocytic [M0025092]
    A low-grade malignant lymphoma that may, in some cases, be considered histologically identical to chronic lymphocytic leukemia (CLL; LEUKEMIA, LYMPHOCYTIC, CHRONIC). It is diffuse in pattern, representing the neoplastic proliferation of well-differentiated B-lymphocytes. In patients with immunoglobulin gammopathies, the lymphocytes may exhibit plasmacytoid characteristics.
  • Lymphoma, Small Noncleaved-Cell [M0025085]
    A high-grade malignant lymphoma that includes both Burkitt tumor (BURKITT LYMPHOMA) and other lymphomas previously designated undifferentiated non-Burkitt type. Nuclei in Burkitt tumor are round to ovoid and uniform in size. The non-Burkitt type exhibits greater nuclear variation and less evidence of cellular maturation with a correspondingly lesser degree of differentiation.
  • Lymphoma, Small-Cell [M0012820]
    A B-cell lymphoma presumably representing a tumor of interfollicular B-lymphocytes that may be functional. Those that are secrete identical immunoglobulin molecules.
  • Lymphoma, T-Cell [M0025079]
    A group of heterogeneous lymphoid tumors representing malignant transformations of T-lymphocytes.
  • Lymphoma, T-Cell, Cutaneous [M0025093]
    A group of lymphomas exhibiting clonal expansion of malignant T-lymphocytes arrested at varying stages of differentiation as well as malignant infiltration of the skin. MYCOSIS FUNGOIDES and SEZARY SYNDROME are the best characterized of these disorders.
  • Lymphoma, T-Cell, Peripheral [M0025095]
    A group of malignant lymphomas thought to derive from peripheral T-lymphocytes in lymph nodes and other nonlymphoid sites. They include a broad spectrum of lymphocyte morphology, but in all instances express T-cell markers admixed with epithelioid histiocytes, plasma cells, and eosinophils. Although markedly similar to large-cell immunoblastic lymphoma (LYMPHOMA, LARGE-CELL, IMMUNOBLASTIC), this group's unique features warrant separate treatment.
  • Lymphoma, Undifferentiated [M0012823]
    A form of lymphoma in which relatively large stem cells with large nuclei, pale, scanty cytoplasm, and indistinct borders are predominant. The cells are undifferentiated, i.e., show no morphologic evidence of maturation toward lymphocytes or histiocytes.
  • Lymphomatoid Granulomatosis [M0012824]
    An angiocentric and angiodestructive lymphoreticular proliferative disorder primarily involving the lungs. Histologically it simulates malignant lymphoma and in some cases may progress to lymphoma.
  • Lymphomatoid Papulosis [M0026796]
    Clinically benign, histologically malignant, recurrent cutaneous eruption characterized by an infiltration of large atypical cells surrounded by inflammatory cells. The atypical cells resemble Reed-Sternberg cells of Hodgkin's disease or the malignant cells of cutaneous T-cell lymphoma. In some cases, lymphomatoid papulosis progresses to lymphomatous conditions including mycosis fungoides, Hodgkin's disease, cutaneous T-cell lymphoma, or Ki-1 lymphoma.
  • Lymphosarcoma, Bovine [M0025295]
  • Lynch Syndrome II [M0004836]
    HNPCC associated with other malignancies, more commonly of ovarian or uterine origin.
  • Macroprolactinoma [M0336981]
  • Male Breast Cancer [M0027831]
  • Malignancies, Post-Traumatic [M0333131]
  • Malignant Brenner Tumor [M0472444]
  • Malignant Cystosarcoma Phyllodes [M0458286]
  • Malignant Glioma [M0337531]
  • Malignant Meningeal Neoplasms [M0337069]
  • Malignant Meningioma [M0337826]
  • Malignant Optic Nerve Neoplasm [M0335892]
  • Malignant Optic Nerve Sheath Neoplasms [M0335893]
  • Malignant Peripheral Nerve Sheath Tumors [M0336462]
  • Malignant Primary Brain Tumors [M0334226]
  • Mammary Carcinoma, Animal [M0445538]
  • Mammary Carcinoma, Human [M0445597]
    Cancer of the human MAMMARY GLAND.
  • Mammary Neoplasms, Animal [M0024029]
    Tumors or cancer of the MAMMARY GLAND in animals (MAMMARY GLANDS, ANIMAL).
  • Mammary Neoplasms, Experimental [M0012963]
    Experimentally induced mammary neoplasms in animals to provide a model for studying human BREAST NEOPLASMS.
  • Mammary Neoplasms, Human [M0445598]
    Tumor or cancer of the human MAMMARY GLAND.
  • Mandibular Neoplasms [M0012980]
    Tumors or cancer of the MANDIBLE.
  • Marek Disease [M0013026]
    A transmissible viral disease of birds caused by avian herpesvirus 2 (HERPESVIRUS 2, GALLID) and other MARDIVIRUS. There is lymphoid cell infiltration or lymphomatous tumor formation in the peripheral nerves and gonads, but may also involve visceral organs, skin, muscle, and the eye.
  • Mast-Cell Sarcoma [M0019438]
    A unifocal malignant tumor that consists of atypical pathological MAST CELLS without systemic involvement. It causes local destructive growth in organs other than in skin or bone marrow.
  • Mastocytoma [M0406150]
    A solid tumor consisting of a dense infiltration of MAST CELLS. It is generally benign.
  • Maxillary Neoplasms [M0013134]
    Cancer or tumors of the MAXILLA or upper jaw.
  • Maxillary Sinus Neoplasms [M0013138]
    Neoplasms or tumors of the maxillary sinus. The majority of paranasal sinus neoplasms arise here. They develop silently when confined to the sinus and produce symptoms on extension through the walls.
  • Mediastinal Neoplasms [M0013199]
    Tumors or cancer of the MEDIASTINUM.
  • Medullary Neoplasms [M0334268]
  • Medulloblastoma [M0013281]
    A malignant neoplasm that may be classified either as a glioma or as a primitive neuroectodermal tumor of childhood (see NEUROECTODERMAL TUMOR, PRIMITIVE). The tumor occurs most frequently in the first decade of life with the most typical location being the cerebellar vermis. Histologic features include a high degree of cellularity, frequent mitotic figures, and a tendency for the cells to organize into sheets or form rosettes. Medulloblastoma have a high propensity to spread throughout the craniospinal intradural axis. (From DeVita et al., Cancer: Principles and Practice of Oncology, 5th ed, pp2060-1)
  • Medulloblastoma, Adult [M0337104]
  • Medulloblastoma, Childhood [M0337105]
  • Medulloepithelioma [M0337490]
  • Medullomyoblastoma [M0013282]
  • Meigs Syndrome [M0013300]
    The triad of benign FIBROMA or other ovarian tumors with ASCITES, and HYDROTHORAX due to large PLEURAL EFFUSIONS.
  • Melanocytic Medulloblastoma [M0337106]
  • Melanocytic Vestibular Schwannoma [M0335873]
  • Melanoma [M0013309]
    A malignant neoplasm derived from cells that are capable of forming melanin, which may occur in the skin of any part of the body, in the eye, or, rarely, in the mucous membranes of the genitalia, anus, oral cavity, or other sites. It occurs mostly in adults and may originate de novo or from a pigmented nevus or malignant lentigo. Melanomas frequently metastasize widely, and the regional lymph nodes, liver, lungs, and brain are likely to be involved. The incidence of malignant skin melanomas is rising rapidly in all parts of the world. (Stedman, 25th ed; from Rook et al., Textbook of Dermatology, 4th ed, p2445)
  • Melanoma, Amelanotic [M0027563]
    An unpigmented malignant melanoma. It is an anaplastic melanoma consisting of cells derived from melanoblasts but not forming melanin. (Dorland, 27th ed; Stedman, 25th ed)
  • Melanoma, B16 [M0013310]
  • Melanoma, Cloudman S91 [M0013311]
  • Melanoma, Experimental [M0013313]
    Experimentally induced tumor that produces MELANIN in animals to provide a model for studying human MELANOMA.
  • Melanoma, Harding-Passey [M0013312]
  • Meningeal Neoplasms [M0013360]
    Benign and malignant neoplastic processes that arise from or secondarily involve the meningeal coverings of the brain and spinal cord.
  • Meningioma [M0013362]
    A relatively common neoplasm of the CENTRAL NERVOUS SYSTEM that arises from arachnoidal cells. The majority are well differentiated vascular tumors which grow slowly and have a low potential to be invasive, although malignant subtypes occur. Meningiomas have a predilection to arise from the parasagittal region, cerebral convexity, sphenoidal ridge, olfactory groove, and SPINAL CANAL. (From DeVita et al., Cancer: Principles and Practice of Oncology, 5th ed, pp2056-7)
  • Meningiomas, Multiple [M0013363]
  • Meningotheliomatous Meningioma [M0337835]
  • Mesencephalic Neoplasms [M0334269]
  • Mesenchymoma [M0013461]
    A mixed mesenchymal tumor composed of two or more mesodermal cellular elements not commonly associated, not counting fibrous tissue as one of the elements. Mesenchymomas are widely distributed in the body and about 75% are malignant. (Dorland, 27th ed; Holland et al., Cancer Medicine, 3d ed, p1866)
  • Mesenteric Cyst [M0013463]
    A rare intra-abdominal tumor in the MESENTERY. Mesenteric cysts are usually benign and can be very large fluid-filled (2000 mL) lesions.
  • Mesonephroma [M0013477]
    A rare tumor of the female genital tract, most often the ovary, formerly considered to be derived from mesonephric rests. Two varieties are recognized: (1) clear cell carcinoma, so called because of its histologic resemblance to renal cell carcinoma, and now considered to be of muellerian duct derivation and (2) an embryonal tumor (called also ENDODERMAL SINUS TUMOR and yolk sac tumor), occurring chiefly in children. The latter variety may also arise in the testis. (Dorland, 27th ed)
  • Mesothelioma [M0013485]
    A tumor derived from mesothelial tissue (peritoneum, pleura, pericardium). It appears as broad sheets of cells, with some regions containing spindle-shaped, sarcoma-like cells and other regions showing adenomatous patterns. Pleural mesotheliomas have been linked to exposure to asbestos. (Dorland, 27th ed)
  • Mesothelioma, Cystic [M0027490]
    A peritoneal mesothelioma affecting mainly young females and producing cysts of variable size and number lined by a single layer of benign mesothelial cells. The disease follows a benign course and is compatible with a normal life expectancy, requiring occasionally partial excision or decompression for relief of pain or other symptoms. Malignant potential is exceptional. (From Holland et al., Cancer Medicine, 3d ed, p1345)
  • Microcystic Meningioma [M0337836]
  • Microprolactinoma [M0336982]
  • Mixed Glioma [M0337530]
  • Mixed Oligodendroglioma-Astrocytoma [M0336854]
  • Mixed Oligodendroglioma-Ependymoma [M0336855]
  • Mixed Pineocytoma-Pineoblastoma [M0454798]
  • Mixed Tumor, Malignant [M0027427]
    A malignant tumor composed of more than one type of neoplastic tissue. (Dorland, 27th ed)
  • Mixed Tumor, Mesodermal [M0027428]
    A sarcoma of the body of the uterus arising in older women, composed of more than one mesenchymal tissue, especially including striated muscle cells. It is associated with previous pelvic radiation exposure in 20% of patients. (Stedman, 25th ed; Holland et al., Cancer Medicine, 3d ed, p1702)
  • Mixed Tumor, Mullerian [M0027429]
    A tumor, basically a carcinoma with a single sarcoma such as leiomyosarcoma or angiosarcoma or multiple sarcomas of uterine origin. The role of estrogen has been postulated as a possible etiological factor in this tumor. (Holland et al., Cancer Medicine, 3d ed, p1703)
  • Mongolian Spot [M0464110]
    A bluish-gray to gray-brown benign, melanocytic nevus found usually in the LUMBOSACRAL REGION of dark-skinned people, especially those of East Asian ancestry. It is usually congenital or appears shortly after birth, and disappears in childhood.
  • Mouth Neoplasms [M0014133]
    Tumors or cancer of the MOUTH.
  • Mucoepidermoid Tumor [M0027532]
    A malignant epithelial tumor of glandular tissue, especially the salivary glands, characterized by acini with mucus-producing cells and by the presence of malignant squamous elements. Most mucoepidermoid tumors are low-grade lesions readily cured by adequate excision. They may appear in any age group. They grow slowly. If high-grade, they behave aggressively, widely infiltrating the salivary gland and producing lymph node and distant metastases. (Dorland, 27th ed; from DeVita Jr et al., Cancer: Principles & Practice of Oncology, 3d ed, p575)
  • Multiple Endocrine Neoplasia [M0014600]
    A group of autosomal dominant diseases characterized by the combined occurrence of tumors involving two or more ENDOCRINE GLANDS that secrete PEPTIDE HORMONES or AMINES. These neoplasias are often benign but can be malignant. They are classified by the endocrine glands involved and the degree of aggressiveness. The two major forms are MEN1 and MEN2 with gene mutations on CHROMOSOME 11 and CHROMOSOME 10, respectively.
  • Multiple Endocrine Neoplasia Type 1 [M0028096]
    A form of multiple endocrine neoplasia that is characterized by the combined occurrence of tumors in the PARATHYROID GLANDS, the PITUITARY GLAND, and the PANCREATIC ISLETS. The resulting clinical signs include HYPERPARATHYROIDISM; HYPERCALCEMIA; HYPERPROLACTINEMIA; CUSHING DISEASE; GASTRINOMA; and ZOLLINGER-ELLISON SYNDROME. This disease is due to loss-of-function of the MEN1 gene, a tumor suppressor gene (GENES, TUMOR SUPPRESSOR) on CHROMOSOME 11 (Locus: 11q13).
  • Multiple Endocrine Neoplasia Type 2a [M0028166]
    A form of multiple endocrine neoplasia characterized by the presence of medullary carcinoma (CARCINOMA, MEDULLARY) of the THYROID GLAND, and usually with the co-occurrence of PHEOCHROMOCYTOMA, producing CALCITONIN and ADRENALINE, respectively. Less frequently, it can occur with hyperplasia or adenoma of the PARATHYROID GLANDS. This disease is due to gain-of-function mutations of the MEN2 gene on CHROMOSOME 10 (Locus: 10q11.2), also known as the RET proto-oncogene that encodes a RECEPTOR PROTEIN-TYROSINE KINASE. It is an autosomal dominant inherited disease.
  • Multiple Endocrine Neoplasia Type 2b [M0028167]
    Similar to MEN2A, it is also caused by mutations of the MEN2 gene, also known as the RET proto-oncogene. Its clinical symptoms include medullary carcinoma (CARCINOMA, MEDULLARY) of THYROID GLAND and PHEOCHROMOCYTOMA of ADRENAL MEDULLA (50%). Unlike MEN2a, MEN2b does not involve PARATHYROID NEOPLASMS. It can be distinguished from MEN2A by its neural abnormalities such as mucosal NEUROMAS on EYELIDS; LIP; and TONGUE, and ganglioneuromatosis of GASTROINTESTINAL TRACT leading to MEGACOLON. It is an autosomal dominant inherited disease.
  • Multiple Hemangioblastomas [M0336752]
  • Multiple Myeloma [M0014195]
    A malignant tumor of plasma cells usually arising in the bone marrow; characterized by diffuse involvement of the skeletal system, hyperglobulinemia, Bence-Jones proteinuria, and anemia.
  • Muscle Neoplasms [M0028431]
    Tumors or cancer located in muscle tissue or specific muscles. They are differentiated from NEOPLASMS, MUSCLE TISSUE which are neoplasms composed of skeletal, cardiac, or smooth muscle tissue, such as MYOSARCOMA or LEIOMYOMA.
  • Mycosis Fungoides [M0014314]
    A chronic malignant T-cell lymphoma of the skin. In the late stages the lymph nodes and viscera are affected.
  • Myelodysplastic Syndromes [M0014324]
    Conditions in which the bone marrow shows qualitative and quantitative changes suggestive of a preleukemic process, but having a chronic course that does not necessarily terminate as acute leukemia.
  • Myeloid Leukemia, Acute, M1 [M0012394]
  • Myelolipoma [M0027438]
    A rare benign tumor of the adrenal gland, several centimeters in diameter, composed in varying proportions of adipose tissue, lymphocytes, and primitive myeloid cells, probably a developmental abnormality. (Dorland, 27th ed)
  • Myeloproliferative Disorders [M0014332]
    Disorders in which one or more stimuli cause proliferation of hemopoietically active tissue or of tissue which has embryonic hemopoietic potential.
  • Myoblastoma [M0014602]
  • Myoepithelioma [M0014348]
    A usually benign tumor made up predominantly of myoepithelial cells.
  • Myofibroblastoma [M0014604]
  • Myofibroma [M0459388]
    A benign tumor that consists chiefly of fibrous CONNECTIVE TISSUE, with variable numbers of MUSCLE CELLS forming portions of the neoplasm (From Stedman's, 27th ed).
  • Myofibromatosis [M0027453]
    A condition characterized by multiple formations of myofibromas (LEIOMYOMA).
  • Myoma [M0014355]
    A benign neoplasm of muscular tissue. (Stedman, 25th ed)
  • Myosarcoma [M0014359]
    A general term for a malignant neoplasm derived from muscular tissue. (Stedman, 25th ed)
  • Myxofibroma [M0008447]
  • Myxoma [M0014383]
    A benign neoplasm derived from connective tissue, consisting chiefly of polyhedral and stellate cells that are loosely embedded in a soft mucoid matrix, thereby resembling primitive mesenchymal tissue. It occurs frequently intramuscularly where it may be mistaken for a sarcoma. It appears also in the jaws and the skin. (From Stedman, 25th ed)
  • Myxosarcoma [M0014388]
    A sarcoma, usually a liposarcoma or malignant fibrous histiocytoma, with an abundant component of myxoid tissue resembling primitive mesenchyme containing connective tissue mucin. (Stedman, 25th ed)
  • Nasopharyngeal Neoplasms [M0014493]
    Tumors or cancer of the NASOPHARYNX.
  • Neck Neoplasms [M0009820]
  • Nelson Syndrome [M0014557]
    A syndrome characterized by HYPERPIGMENTATION, enlarging pituitary mass, visual defects secondary to compression of the OPTIC CHIASM, and elevated serum ACTH. It is caused by the expansion of an underlying ACTH-SECRETING PITUITARY ADENOMA that grows in the absence of feedback inhibition by adrenal CORTICOSTEROIDS, usually after ADRENALECTOMY.
  • Neoplasm Metastasis [M0014577]
    The transfer of a neoplasm from one organ or part of the body to another remote from the primary site.
  • Neoplasm Metastasis, Unknown Primary [M0014608]
  • Neoplasm Recurrence, Local [M0014579]
    The local recurrence of a neoplasm following treatment. It arises from microscopic cells of the original neoplasm that have escaped therapeutic intervention and later become clinically visible at the original site.
  • Neoplasm, Residual [M0027593]
    Remnant of a tumor or cancer after primary, potentially curative therapy. (Dr. Daniel Masys, written communication)
  • Neoplasms [M0014585]
    New abnormal growth of tissue. Malignant neoplasms show a greater degree of anaplasia and have the properties of invasion and metastasis, compared to benign neoplasms.
  • Neoplasms by Histologic Type [M0014588]
    A collective term for the various histological types of NEOPLASMS. It is more likely to be used by searchers than by indexers and catalogers.
  • Neoplasms by Site [M0014589]
    A collective term for precoordinated organ/neoplasm headings locating neoplasms by organ, as BRAIN NEOPLASMS; DUODENAL NEOPLASMS; LIVER NEOPLASMS; etc.
  • Neoplasms, Adipose Tissue [M0027434]
    Neoplasms composed of fatty tissue or connective tissue made up of fat cells in a meshwork of areolar tissue. The concept does not refer to neoplasms located in adipose tissue.
  • Neoplasms, Adnexal and Skin Appendage [M0027528]
    Neoplasms composed of sebaceous or sweat gland tissue or tissue of other skin appendages. The concept does not refer to neoplasms located in the sebaceous or sweat glands or in the other skin appendages.
  • Neoplasms, Basal Cell [M0027529]
    Neoplasms composed of cells from the deepest layer of the epidermis. The concept does not refer to neoplasms located in the stratum basale.
  • Neoplasms, Bone Tissue [M0027442]
    Neoplasms composed of bony tissue, whether normal or of a soft tissue which has become ossified. The concept does not refer to neoplasms located in bones.
  • Neoplasms, Complex and Mixed [M0027422]
    Neoplasms composed of more than one type of neoplastic tissue.
  • Neoplasms, Connective and Soft Tissue [M0027433]
    Neoplasms developing from some structure of the connective and subcutaneous tissue. The concept does not refer to neoplasms located in connective or soft tissue.
  • Neoplasms, Connective Tissue [M0014590]
    Neoplasms composed of connective tissue, including elastic, mucous, reticular, osseous, and cartilaginous tissue. The concept does not refer to neoplasms located in connective tissue.
  • Neoplasms, Cystic, Mucinous, and Serous [M0027531]
    Neoplasms containing cyst-like formations or producing mucin or serum.
  • Neoplasms, Dental Tissue [M0015223]
  • Neoplasms, Ductal, Lobular, and Medullary [M0027533]
    Neoplasms, usually carcinoma, located within the center of an organ or within small lobes, and in the case of the breast, intraductally. The emphasis of the name is on the location of the neoplastic tissue rather than on its histological type. Most cancers of this type are located in the breast.
  • Neoplasms, Embryonal [M0014591]
  • Neoplasms, Embryonal and Mixed [M0014594]
  • Neoplasms, Epithelial [M0014597]
  • Neoplasms, Experimental [M0014595]
    Experimentally induced new abnormal growth of TISSUES in animals to provide models for studying human neoplasms.
  • Neoplasms, Fibroepithelial [M0027454]
    Neoplasms composed of fibrous and epithelial tissue. The concept does not refer to neoplasms located in fibrous tissue or epithelium.
  • Neoplasms, Fibrous Tissue [M0027447]
    Neoplasms composed of fibrous tissue, the ordinary connective tissue of the body, made up largely of yellow or white fibers. The concept does not refer to neoplasms located in fibrous tissue.
  • Neoplasms, Germ Cell [M0482530]
  • Neoplasms, Germ Cell and Embryonal [M0014592]
    Neoplasms composed of primordial GERM CELLS of embryonic GONADS or of elements of the germ layers of the EMBRYO. The concept does not refer to neoplasms located in the gonads or present in an embryo or FETUS.
  • Neoplasms, Glandular and Epithelial [M0014596]
    Neoplasms composed of glandular tissue, an aggregation of epithelial cells that elaborate secretions, and of any type of epithelium itself. The concept does not refer to neoplasms located in the various glands or in epithelial tissue.
  • Neoplasms, Gonadal Tissue [M0027544]
    Neoplasms composed of tissues of the OVARY or the TESTIS, not neoplasms located in the ovaries or testes. Gonadal tissues include GERM CELLS, cells from the sex cord, and gonadal stromal cells.
  • Neoplasms, Hormone-Dependent [M0014599]
    Certain tumors that 1, arise in organs that are normally dependent on specific hormones and 2, are stimulated or caused to regress by manipulation of the endocrine environment.
  • Neoplasms, Intracranial [M0334227]
  • Neoplasms, Intraepithelial [M0371198]
  • Neoplasms, Mesothelial [M0027535]
    Neoplasms composed of tissue of the mesothelium, the layer of flat cells, derived from the mesoderm, which lines the body cavity of the embryo. In the adult it forms the simple squamous epithelium which covers all true serous membranes (peritoneum, pericardium, pleura). The concept does not refer to neoplasms located in these organs. (From Dorland, 27th ed)
  • Neoplasms, Multiple Primary [M0014601]
    Two or more abnormal growths of tissue occurring simultaneously. The neoplasms are histologically different and may be found in the same or different sites.
  • Neoplasms, Muscle Tissue [M0014603]
    Neoplasms composed of muscle tissue: skeletal, cardiac, or smooth. The concept does not refer to neoplasms located in muscles.
  • Neoplasms, Nerve Tissue [M0014605]
    Neoplasms composed of nerve tissue. This concept does not refer to neoplasms located in the nervous system or its component nerves.
  • Neoplasms, Neuroepithelial [M0027536]
    Neoplasms composed of neuroepithelial cells, which have the capacity to differentiate into NEURONS, oligodendrocytes, and ASTROCYTES. The majority of craniospinal tumors are of neuroepithelial origin. (From Dev Biol 1998 Aug 1;200(1):1-5)
  • Neoplasms, Post-Traumatic [M0026070]
    Tumors, cancer or other neoplasms caused by or resulting from trauma or other non-radiation injuries.
  • Neoplasms, Radiation-Induced [M0014606]
    Tumors, cancer or other neoplasms produced by exposure to ionizing or non-ionizing radiation.
  • Neoplasms, Second Primary [M0025328]
    Abnormal growths of tissue that follow a previous neoplasm but are not metastases of the latter. The second neoplasm may have the same or different histological type and can occur in the same or different organs as the previous neoplasm but in all cases arises from an independent oncogenic event. The development of the second neoplasm may or may not be related to the treatment for the previous neoplasm since genetic risk or predisposing factors may actually be the cause.
  • Neoplasms, Squamous Cell [M0027541]
    Neoplasms composed of squamous cells of the epithelium. The concept does not refer to neoplasms located in tissue composed of squamous elements.
  • Neoplasms, Therapy-Associated [M0025329]
  • Neoplasms, Unknown Primary [M0014607]
    Metastases in which the tissue of origin is unknown.
  • Neoplasms, Vascular Tissue [M0014610]
    Neoplasms composed of vascular tissue. This concept does not refer to neoplasms located in blood vessels.
  • Neoplastic Processes [M0014612]
    The pathological mechanisms and forms taken by tissue during degeneration into a neoplasm and its subsequent activity.
  • Neoplastic Syndromes, Hereditary [M0014613]
    The condition of a pattern of malignancies within a family, but not every individual's necessarily having the same neoplasm. Characteristically the tumor tends to occur at an earlier than average age, individuals may have more than one primary tumor, the tumors may be multicentric, usually more than 25 percent of the individuals in direct lineal descent from the proband are affected, and the cancer predisposition in these families behaves as an autosomal dominant trait with about 60 percent penetrance.
  • Nephroma, Mesoblastic [M0027430]
    A solid, unencapsulated tumor of the KIDNEY composed of spindle mesenchymal cells that resemble FIBROBLASTS or muscle cells. The homogeneous mass typically extends into the renal parenchyma and replaces most of the kidney. In most cases, mesoblastic nephroma is benign and occurs in the fetus or newborn, and rarely in the older child or the adult.
  • Nerve Sheath Neoplasms [M0027552]
    Neoplasms which arise from nerve sheaths formed by SCHWANN CELLS in the PERIPHERAL NERVOUS SYSTEM or by OLIGODENDROCYTES in the CENTRAL NERVOUS SYSTEM. Malignant peripheral nerve sheath tumors, NEUROFIBROMA, and NEURILEMMOMA are relatively common tumors in this category.
  • Nervous System Neoplasms [M0014668]
    Benign and malignant neoplastic processes arising from or involving components of the central, peripheral, and autonomic nervous systems, cranial nerves, and meninges. Included in this category are primary and metastatic nervous system neoplasms.
  • Neurilemmoma [M0014692]
    A neoplasm that arises from SCHWANN CELLS of the cranial, peripheral, and autonomic nerves. Clinically, these tumors may present as a cranial neuropathy, abdominal or soft tissue mass, intracranial lesion, or with spinal cord compression. Histologically, these tumors are encapsulated, highly vascular, and composed of a homogenous pattern of biphasic fusiform-shaped cells that may have a palisaded appearance. (From DeVita Jr et al., Cancer: Principles and Practice of Oncology, 5th ed, pp964-5)
  • Neurilemmosarcoma [M0336465]
  • Neuroblastoma [M0014699]
    A common neoplasm of early childhood arising from neural crest cells in the sympathetic nervous system, and characterized by diverse clinical behavior, ranging from spontaneous remission to rapid metastatic progression and death. This tumor is the most common intraabdominal malignancy of childhood, but it may also arise from thorax, neck, or rarely occur in the central nervous system. Histologic features include uniform round cells with hyperchromatic nuclei arranged in nests and separated by fibrovascular septa. Neuroblastomas may be associated with the opsoclonus-myoclonus syndrome. (From DeVita et al., Cancer: Principles and Practice of Oncology, 5th ed, pp2099-2101; Curr Opin Oncol 1998 Jan;10(1):43-51)
  • Neurocutaneous Syndromes [M0328284]
    A group of disorders characterized by ectodermal-based malformations and neoplastic growths in the skin, nervous system, and other organs.
  • Neurocytoma [M0027540]
    A benign brain tumor composed of neural elements which most often arise from the SEPTUM PELLUCIDUM and the walls of the lateral ventricles. Immunohistochemistry and electron microscopy evaluations may reveal expression of neuron specific enolase and synaptophysin and cells containing microtubuli, neurosecretory granules, and presynaptic vesicles. (From Acta Med Port 1994 Feb;7(2):113-9)
  • Neurocytoma, Central [M0336850]
  • Neuroectodermal Tumor, Melanotic [M0026669]
    A benign, rapidly growing, deeply pigmented tumor of the jaw and occasionally of other sites, consisting of an infiltrating mass of cells arranged in an alveolar pattern, and occurring almost exclusively in infants. Its source of origin is in dispute, the various theories giving rise to its several names. (Dorland, 27th ed)
  • Neuroectodermal Tumors [M0026668]
    Malignant neoplasms arising in the neuroectoderm, the portion of the ectoderm of the early embryo that gives rise to the central and peripheral nervous systems, including some glial cells.
  • Neuroectodermal Tumors, Primitive [M0027471]
    A group of malignant tumors of the nervous system that feature primitive cells with elements of neuronal and/or glial differentiation. Use of this term is limited by some authors to central nervous system tumors and others include neoplasms of similar origin which arise extracranially (i.e., NEUROECTODERMAL TUMORS, PRIMITIVE, PERIPHERAL). This term is also occasionally used as a synonym for MEDULLOBLASTOMA. In general, these tumors arise in the first decade of life and tend to be highly malignant. (From DeVita et al., Cancer: Principles and Practice of Oncology, 5th ed, p2059)
  • Neuroectodermal Tumors, Primitive, Peripheral [M0027470]
    A group of highly cellular primitive round cell neoplasms which occur extracranially in soft tissue and bone and are derived from embryonal neural crest cells. These tumors occur primarily in children and adolescents and share a number of characteristics with Ewing's Sarcoma (SARCOMA, EWING'S). They may arise from the chest wall, skin, orbit, kidney, and other structures and tend to be locally invasive or metastasize, although relatively benign forms may occur. Characteristic histologic features include a tendency to form Homer-Wright rosettes and to stain positively with neuron-specific enolase and vimentin. (From DeVita et al., Cancer: Principles and Practice of Oncology, 5th ed, p2113; J Clin Oncol 1998 Mar;16(3):1150-7)
  • Neuroendocrine Tumors [M0027590]
    Tumors whose cells possess secretory granules and originate from the neuroectoderm, i.e., the cells of the ectoblast or epiblast that program the neuroendocrine system. Common properties across most neuroendocrine tumors include ectopic hormone production (often via APUD CELLS), the presence of tumor-associated antigens, and isozyme composition.
  • Neuroepithelioma [M0014707]
  • Neurofibroma [M0014709]
    A moderately firm, benign, encapsulated tumor resulting from proliferation of SCHWANN CELLS and FIBROBLASTS that includes portions of nerve fibers. The tumors usually develop along peripheral or cranial nerves and are a central feature of NEUROFIBROMATOSIS 1, where they may occur intracranially or involve spinal roots. Pathologic features include fusiform enlargement of the involved nerve. Microscopic examination reveals a disorganized and loose cellular pattern with elongated nuclei intermixed with fibrous strands. (From Adams et al., Principles of Neurology, 6th ed, p1016)
  • Neurofibroma, Plexiform [M0027553]
    A type of neurofibroma manifesting as a diffuse overgrowth of subcutaneous tissue, usually involving the face, scalp, neck, and chest but occasionally occurring in the abdomen or pelvis. The tumors tend to progress, and may extend along nerve roots to eventually involve the spinal roots and spinal cord. This process is almost always a manifestation of NEUROFIBROMATOSIS 1. (From Adams et al., Principles of Neurology, 6th ed, p1016; J Pediatr 1997 Nov;131(5):678-82)
  • Neurofibromatoses [M0026175]
    A group of disorders characterized by an autosomal dominant pattern of inheritance with high rates of spontaneous mutation and multiple neurofibromas or neurilemmomas. NEUROFIBROMATOSIS 1 (generalized neurofibromatosis) accounts for approximately 95% of cases, although multiple additional subtypes (e.g., NEUROFIBROMATOSIS 2, neurofibromatosis 3, etc.) have been described. (From Neurochirurgie 1998 Nov;44(4):267-72)
  • Neurofibromatosis 1 [M0014710]
    An autosomal dominant inherited disorder (with a high frequency of spontaneous mutations) that features developmental changes in the nervous system, muscles, bones, and skin, most notably in tissue derived from the embryonic NEURAL CREST. Multiple hyperpigmented skin lesions and subcutaneous tumors are the hallmark of this disease. Peripheral and central nervous system neoplasms occur frequently, especially OPTIC NERVE GLIOMA and NEUROFIBROSARCOMA. NF1 is caused by mutations which inactivate the NF1 gene (GENES, NEUROFIBROMATOSIS 1) on chromosome 17q. The incidence of learning disabilities is also elevated in this condition. (From Adams et al., Principles of Neurology, 6th ed, pp1014-18) There is overlap of clinical features with NOONAN SYNDROME in a syndrome called neurofibromatosis-Noonan syndrome. Both the PTPN11 and NF1 gene products are involved in the SIGNAL TRANSDUCTION pathway of Ras (RAS PROTEINS).
  • Neurofibromatosis 2 [M0025211]
    An autosomal dominant disorder characterized by a high incidence of bilateral acoustic neuromas as well as schwannomas (NEURILEMMOMA) of other cranial and peripheral nerves, and other benign intracranial tumors including meningiomas, ependymomas, spinal neurofibromas, and gliomas. The disease has been linked to mutations of the NF2 gene (GENES, NEUROFIBROMATOSIS 2) on chromosome 22 (22q12) and usually presents clinically in the first or second decade of life.
  • Neurofibromatosis 3 [M0337469]
  • Neurofibrosarcoma [M0027554]
    A malignant tumor that arises from small cutaneous nerves, is locally aggressive, and has a potential for metastasis. Characteristic histopathologic features include proliferating atypical spindle cells with slender wavy and pointed nuclei, hypocellular areas, and areas featuring organized whorls of fibroblastic proliferation. The most common primary sites are the extremities, retroperitoneum, and trunk. These tumors tend to present in childhood, often in association with NEUROFIBROMATOSIS 1. (From DeVita et al., Cancer: Principles & Practice of Oncology, 5th ed, p1662; Mayo Clin Proc 1990 Feb;65(2):164-72)
  • Neuroma [M0014718]
    A tumor made up of nerve cells and nerve fibers. (Dorland, 27th ed)
  • Neuroma, Acoustic, Bilateral [M0406512]
  • Neuroma, Acoustic, Unilateral [M0014720]
  • Neurothekeoma [M0027556]
    A benign myxoma of cutaneous nerve sheath origin. Theke is from the Greek theke, sheath. (From Stedman, 25th ed)
  • Nevi and Melanomas [M0027561]
    A collective term for the various types of nevi and melanomas.
  • Nevus [M0014786]
    A circumscribed stable malformation of the skin and occasionally of the oral mucosa, which is not due to external causes and therefore presumed to be of hereditary origin.
  • Nevus of Ota [M0014787]
    A macular lesion on the side of the FACE, involving the CONJUNCTIVA and EYELIDS, as well as the adjacent facial skin, SCLERA; OCULOMOTOR MUSCLES; and PERIOSTEUM. Histological features vary from those of a MONGOLIAN SPOT to those of a BLUE NEVUS.
  • Nevus, Blue [M0027564]
    Usually a benign tumor, that commonly presents as a solitary blue nodule with spindled MELANOCYTES covered by smooth SKIN. Several variants have been identified, one variant being malignant. The blue color is caused by large, densely packed melanocytes deep in the DERMIS of the nevus. In CHILDREN, they usually occur on the BUTTOCKS and LUMBOSACRAL REGION and are referred to as cellular blue nevi. Malignant blue nevi are more commonly found on the SCALP.
  • Nevus, Epithelioid and Spindle Cell [M0027567]
    A benign compound nevus occurring most often in children before puberty, composed of spindle and epithelioid cells located mainly in the dermis, sometimes in association with large atypical cells and multinucleate cells, and having a close histopathological resemblance to malignant melanoma. The tumor presents as a smooth to slightly scaly, round to oval, raised, firm papule or nodule, ranging in color from pink-tan to purplish red, often with surface telangiectasia. (Dorland, 27th ed)
  • Nevus, Intradermal [M0027565]
    A nevus in which nests of melanocytes are found in the dermis, but not at the epidermal-dermal junction. Benign pigmented nevi in adults are most commonly intradermal. (Stedman, 25th ed)
  • Nevus, Pigmented [M0014788]
    A nevus containing melanin. The term is usually restricted to nevocytic nevi (round or oval collections of melanin-containing nevus cells occurring at the dermoepidermal junction of the skin or in the dermis proper) or moles, but may be applied to other pigmented nevi. (From Dorland, 27th ed)
  • Nevus, Spindle Cell [M0027566]
    A form of pigmented nevus showing intense melanocytic activity around the dermo-epidermal junction. Large numbers of spindle-shaped melanocytes proliferate downward toward the dermis and usually a large amount of pigment is present. It was first described in 1976 and the bulk of patients reported have been young females with the lesions presenting on the thighs. (From Rook et al., Textbook of Dermatology, 4th ed, 1992, p185)
  • Nose Neoplasms [M0015013]
    Tumors or cancer of the NOSE.
  • Odontogenic Cyst, Calcifying [M0027568]
    A mixed radiolucent-radiopaque lesion of the jaws with features of both a cyst and a solid neoplasm. It is characterized microscopically by an epithelial lining showing a palisaded layer of columnar basal cells, presence of ghost cell keratinization, dentinoid, and calcification. (Stedman, 25th ed)
  • Odontogenic Tumor, Squamous [M0480893]
    A well-differentiated, benign, hamartomatous proliferation of odontogenic epithelium, probably arising from the rests of Malassez.
  • Odontogenic Tumors [M0015224]
    Neoplasms produced from tooth-forming tissues.
  • Odontoma [M0015226]
    A mixed tumor of odontogenic origin, in which both the epithelial and mesenchymal cells exhibit complete differentiation, resulting in the formation of tooth structures. (Jablonski, Illustrated Dictionary of Dentistry, 1982)
  • Odontoma, Compound [M0015228]
  • Olfactory Groove Meningioma [M0481064]
  • Oligoastrocytoma, Mixed [M0336532]
  • Oligodendroblastoma [M0015274]
  • Oligodendroglioma [M0015273]
    A relatively slow-growing glioma that is derived from oligodendrocytes and tends to occur in the cerebral hemispheres, thalamus, or lateral ventricle. They may present at any age, but are most frequent in the third to fifth decades, with an earlier incidence peak in the first decade. Histologically, these tumors are encapsulated, relatively avascular, and tend to form cysts and microcalcifications. Neoplastic cells tend to have small round nuclei surrounded by unstained nuclei. The tumors may vary from well-differentiated to highly anaplastic forms. (From DeVita et al., Cancer: Principles and Practice of Oncology, 5th ed, p2052; Adams et al., Principles of Neurology, 6th ed, p655)
  • Oligodendroglioma, Adult [M0336856]
  • Oligodendroglioma, Childhood [M0336857]
  • Oligodendroglioma, Well-Differentiated [M0336858]
  • Optic Nerve Glioma [M0328319]
    Glial cell derived tumors arising from the optic nerve, usually presenting in childhood. Roughly 50% are associated with NEUROFIBROMATOSIS 1. Clinical manifestations include decreased visual acuity; EXOPHTHALMOS; NYSTAGMUS, PATHOLOGIC; STRABISMUS; pallor or swelling of the optic disc; and INTRACRANIAL HYPERTENSION. The tumor may extend into the optic chiasm and hypothalamus. (Adams et al., Principles of Neurology, 6th ed, p681)
  • Optic Nerve Neoplasms [M0029064]
    Benign and malignant neoplasms that arise from the optic nerve or its sheath. OPTIC NERVE GLIOMA is the most common histologic type. Optic nerve neoplasms tend to cause unilateral visual loss and an afferent pupillary defect and may spread via neural pathways to the brain.
  • Optic Nerve Sheath Neoplasm [M0335889]
  • Orbital Neoplasms [M0015380]
    Neoplasms of the bony orbit and contents except the eyeball.
  • Oropharyngeal Neoplasms [M0015441]
    Tumors or cancer of the OROPHARYNX.
  • Osgood-Schlatter Disease [M0015517]
  • Osteoblastoma [M0027444]
    A benign, painful, tumor of bone characterized by the formation of osteoid tissue, primitive bone and calcified tissue. It occurs frequently in the spine of young persons. (From Dorland, 27th ed; Stedman, 25th ed)
  • Osteochondroma [M0024248]
    A cartilage-capped benign tumor that often appears as a stalk on the surface of bone. It is probably a developmental malformation rather than a true neoplasm and is usually found in the metaphysis of the distal femur, proximal tibia, or proximal humerus. Osteochondroma is the most common of benign bone tumors.
  • Osteochondromatosis [M0027445]
    A condition marked by the presence of multiple osteochondromas. (Dorland, 27th ed)
  • Osteoma [M0015541]
    A benign tumor composed of bone tissue or a hard tumor of bonelike structure developing on a bone (homoplastic osteoma) or on other structures (heteroplastic osteoma). (From Dorland, 27th ed)
  • Osteoma, Osteoid [M0015542]
    Benign circumscribed tumor of spongy bone occurring especially in the bones of the extremities and vertebrae, most often in young persons. (Dorland, 27th ed)
  • Osteosarcoma [M0019439]
    A sarcoma originating in bone-forming cells, affecting the ends of long bones. It is the most common and most malignant of sarcomas of the bones, and occurs chiefly among 10- to 25-year-old youths. (From Stedman, 25th ed)
  • Osteosarcoma, Juxtacortical [M0027446]
    A form of osteogenic sarcoma of relatively low malignancy, probably arising from the periosteum and initially involving cortical bone and adjacent connective tissue. It occurs in middle-aged as well as young adults and most commonly affects the lower part of the femoral shaft. (Stedman, 25th ed)
  • Otorhinolaryngologic Neoplasms [M0015573]
    The general concept of ORL neoplasms or those for which no specific heading exists.
  • Ovarian Neoplasms [M0015593]
    Tumors or cancer of the OVARY. These neoplasms can be benign or malignant. They are classified according to the tissue of origin, such as the surface EPITHELIUM, the stromal endocrine cells, and the totipotent GERM CELLS.
  • Ovary Cancer [M0015592]
  • Paget's Disease, Extramammary [M0015741]
    A rare cutaneous neoplasm that occurs in the elderly. It develops more frequently in women and predominantly involves apocrine gland-bearing areas, especially the vulva, scrotum, and perianal areas. The lesions develop as erythematous scaly patches that progress to crusted, pruritic, erythematous plaques. The clinical differential diagnosis includes squamous cell carcinoma in situ and superficial fungal infection. It is generally thought to be an adenocarcinoma of the epidermis, from which it extends into the contiguous epithelium of hair follicles and eccrine sweat ducts. (DeVita Jr et al., Cancer: Principles & Practice of Oncology, 3d ed, p1478)
  • Paget's Disease, Mammary [M0015740]
    An intraductal carcinoma of the breast extending to involve the nipple and areola, characterized clinically by eczema-like inflammatory skin changes and histologically by infiltration of the dermis by malignant cells (Paget's cells). (Dorland, 27th ed)
  • Palatal Neoplasms [M0015761]
    Tumors or cancer of the PALATE, including those of the hard palate, soft palate and UVULA.
  • Pancoast's Syndrome [M0015789]
    Destructive lesions of the thoracic inlet with involvement of the brachial and sympathetic plexus or carcinoma of the lung apex. It is characterized by pain in the shoulder region radiating toward the axilla and scapula, sensory and motor disorders and wasting of the muscles of the hand, the Bernard-Horner syndrome, and compression of the blood vessels with edema. (Jablonski's Dictionary of Syndromes and Eponymic Diseases, 2d ed)
  • Pancreatic Neoplasms [M0015803]
    Tumors or cancer of the PANCREAS. Depending on the types of ISLET CELLS present in the tumors, various hormones can be secreted: GLUCAGON from PANCREATIC ALPHA CELLS; INSULIN from PANCREATIC BETA CELLS; and SOMATOSTATIN from the SOMATOSTATIN-SECRETING CELLS. Most are malignant except the insulin-producing tumors (INSULINOMA).
  • Papillary Meningioma [M0337837]
  • Papillary Renal Cell Carcinoma [M0483486]
  • Papilloma [M0015836]
    A circumscribed benign epithelial tumor projecting from the surrounding surface; more precisely, a benign epithelial neoplasm consisting of villous or arborescent outgrowths of fibrovascular stroma covered by neoplastic cells. (Stedman, 25th ed)
  • Papilloma, Choroid Plexus [M0009274]
    A usually benign neoplasm that arises from the cuboidal epithelium of the choroid plexus and takes the form of an enlarged CHOROID PLEXUS, which may be associated with oversecretion of CSF. The tumor usually presents in the first decade of life with signs of increased intracranial pressure including HEADACHES; ATAXIA; DIPLOPIA; and alterations of mental status. In children it is most common in the lateral ventricles and in adults it tends to arise in the fourth ventricle. Malignant transformation to choroid plexus carcinomas may rarely occur. (Adams et al., Principles of Neurology, 6th ed, p667; DeVita et al., Cancer: Principles and Practice of Oncology, 5th ed, p2072)
  • Papilloma, Intraductal [M0027534]
    A small, often impalpable benign papilloma arising in a lactiferous duct and frequently causing bleeding from the nipple. (Stedman, 25th ed)
  • Papilloma, Inverted [M0027542]
    A mucosal tumor of the urinary bladder or nasal cavity in which proliferating epithelium is invaginated beneath the surface and is more smoothly rounded than in other papillomas. (Stedman, 25th ed)
  • Papilloma, Shope [M0022155]
  • Papilloma, Squamous Cell [M0015837]
  • Papillomatosis [M0015838]
  • Paraganglioma [M0015869]
    A neural crest tumor usually derived from the chromoreceptor tissue of a paraganglion, such as the carotid body, or medulla of the adrenal gland (usually called a chromaffinoma or pheochromocytoma). It is more common in women than in men. (Stedman, 25th ed; from Segen, Dictionary of Modern Medicine, 1992)
  • Paraganglioma, Extra-Adrenal [M0015870]
    A relatively rare, usually benign neoplasm originating in the chemoreceptor tissue of the CAROTID BODY; GLOMUS JUGULARE; GLOMUS TYPANICUM;, and AORTIC BODIES. It consists histologically of rounded or ovoid hyperchromatic cells that tend to be grouped in an alveolus-like pattern within a scant to moderate amount of fibrous stroma and a few large thin-walled vascular channels. (From Stedman, 27th ed)
  • Paranasal Sinus Neoplasms [M0015893]
    Neoplasms or tumors of the paranasal sinuses. Malignant neoplasms are rare, comprising 3% of all head and neck neoplasms. The majority arise in the maxillary sinus with malignancies of the ethmoid sinus constituting virtually all the remaining tumors.
  • Paraneoplastic Syndromes [M0015895]
    In patients with neoplastic diseases a wide variety of clinical pictures which are indirect and usually remote effects produced by tumor cell metabolites or other products.
  • Paraproteinemias [M0015905]
    A group of related diseases characterized by an unbalanced or disproportionate proliferation of immunoglobulin-producing cells, usually from a single clone. These cells frequently secrete a structurally homogeneous immunoglobulin (M-component) and/or an abnormal immunoglobulin.
  • Parasagittal Meningioma [M0337838]
  • Parathyroid Adenoma [M0470787]
  • Parathyroid Carcinoma [M0333234]
  • Parathyroid Neoplasms [M0015932]
    Tumors or cancer of the PARATHYROID GLANDS.
  • Parotid Neoplasms [M0015975]
    Tumors or cancer of the PAROTID GLAND.
  • Pelvic Neoplasms [M0016102]
    Tumors or cancer of the pelvic region.
  • Penile Neoplasms [M0016160]
    Cancers or tumors of the PENIS or of its component tissues.
  • Perineurioma [M0336463]
  • Peripheral Nerve Neoplasms, Benign [M0336457]
  • Peripheral Nerve Neoplasms, Malignant [M0336458]
  • Peripheral Nerve Neoplastic Infiltration [M0336459]
  • Peripheral Nerve Sheath Tumors [M0336464]
  • Peripheral Nervous System Neoplasms [M0016348]
    Neoplasms which arise from peripheral nerve tissue. This includes NEUROFIBROMAS; SCHWANNOMAS; GRANULAR CELL TUMORS; and malignant peripheral NERVE SHEATH NEOPLASMS. (From DeVita Jr et al., Cancer: Principles and Practice of Oncology, 5th ed, pp1750-1)
  • Peritoneal Neoplasms [M0016362]
    Tumors or cancer of the PERITONEUM.
  • Peutz-Jeghers Syndrome [M0016441]
    A hereditary disease caused by autosomal dominant mutations involving CHROMOSOME 19. It is characterized by the presence of INTESTINAL POLYPS, consistently in the JEJUNUM, and mucocutaneous pigmentation with MELANIN spots of the lips, buccal MUCOSA, and digits.
  • Pharyngeal Neoplasms [M0016481]
    Tumors or cancer of the PHARYNX.
  • Pheochromocytoma [M0016586]
    A usually benign, well-encapsulated, lobular, vascular tumor of chromaffin tissue of the ADRENAL MEDULLA or sympathetic paraganglia. The cardinal symptom, reflecting the increased secretion of EPINEPHRINE and NOREPINEPHRINE, is HYPERTENSION, which may be persistent or intermittent. During severe attacks, there may be HEADACHE; SWEATING, palpitation, apprehension, TREMOR; PALLOR or FLUSHING of the face, NAUSEA and VOMITING, pain in the CHEST and ABDOMEN, and paresthesias of the extremities. The incidence of malignancy is as low as 5% but the pathologic distinction between benign and malignant pheochromocytomas is not clear. (Dorland, 27th ed; DeVita Jr et al., Cancer: Principles & Practice of Oncology, 3d ed, p1298)
  • Pheochromocytoma, Extra-Adrenal [M0444542]
  • Phyllodes Tumor [M0005559]
    A type of connective tissue neoplasm arising from intralobular stroma of the BREAST. It is characterized by the rapid enlargement of an asymmetric firm mobile mass. Histologically, its leaf-like stromal clefts are lined by EPITHELIAL CELLS.
  • Pilocytic Astrocytoma [M0336543]
  • Pilomatrixoma [M0027530]
    A tumor composed of cells resembling those of the hair matrix, which undergo 'mummification' and may calcify. It is a relatively uncommon tumor, which may occur at any age from infancy. The majority of patients are under 20, and females are affected more than males. The lesion is usually a solitary deep dermal or subcutaneous tumor 3-30 mm in diameter, situated in the head, neck, or upper extremity. (From Rook et al., Textbook of Dermatology, 4th ed, p2401)
  • Pinealocytoma [M0359299]
  • Pinealoma [M0016875]
    Neoplasms which originate from pineal parenchymal cells that tend to enlarge the gland and be locally invasive. The two major forms are pineocytoma and the more malignant pineoblastoma. Pineocytomas have moderate cellularity and tend to form rosette patterns. Pineoblastomas are highly cellular tumors containing small, poorly differentiated cells. These tumors occasionally seed the neuroaxis or cause obstructive HYDROCEPHALUS or Parinaud's syndrome. GERMINOMA; CARCINOMA, EMBRYONAL; GLIOMA; and other neoplasms may arise in the pineal region with germinoma being the most common pineal region tumor. (From DeVita et al., Cancer: Principles and Practice of Oncology, 5th ed, p2064; Adams et al., Principles of Neurology, 6th ed, p670)
  • Pineoblastoma [M0016876]
  • Pituitary Adenoma [M0470808]
  • Pituitary Carcinoma [M0470807]
  • Pituitary Neoplasms [M0016922]
    Neoplasms which arise from or metastasize to the PITUITARY GLAND. The majority of pituitary neoplasms are adenomas, which are divided into non-secreting and secreting forms. Hormone producing forms are further classified by the type of hormone they secrete. Pituitary adenomas may also be characterized by their staining properties (see ADENOMA, BASOPHIL; ADENOMA, ACIDOPHIL; and ADENOMA, CHROMOPHOBE). Pituitary tumors may compress adjacent structures, including the HYPOTHALAMUS, several CRANIAL NERVES, and the OPTIC CHIASM. Chiasmal compression may result in bitemporal HEMIANOPSIA.
  • Plant Tumors [M0016963]
    A localized proliferation of plant tissue forming a swelling or outgrowth, commonly with a characteristic shape and unlike any organ of the normal plant. Plant tumors or galls usually form in response to the action of a pathogen or a pest. (Holliday, P., A Dictionary of Plant Pathology, 1989, p330)
  • Plasma Cell Dyscrasias [M0408254]
  • Plasmacytoma [M0016982]
    Any discrete, presumably solitary, mass of neoplastic plasma cells either in bone marrow or various extramedullary sites.
  • Pleural Effusion, Malignant [M0024554]
    Presence of fluid in the pleural cavity as a complication of malignant disease. Malignant pleural effusions often contain actual malignant cells.
  • Pleural Neoplasms [M0017044]
    Neoplasms of the thin serous membrane that envelopes the lungs and lines the thoracic cavity. Pleural neoplasms are exceedingly rare and are usually not diagnosed until they are advanced because in the early stages they produce no symptoms.
  • Polycythemia Vera [M0017168]
    A myeloproliferative disorder of unknown etiology, characterized by abnormal proliferation of all hematopoietic bone marrow elements and an absolute increase in red cell mass and total blood volume, associated frequently with splenomegaly, leukocytosis, and thrombocythemia. Hematopoiesis is also reactive in extramedullary sites (liver and spleen). In time myelofibrosis occurs.
  • Pontine Tumors [M0334270]
  • Posterior Fossa Meningioma [M0481062]
  • Precancerous Conditions [M0017448]
    Pathological processes that tend eventually to become malignant. (From Dorland, 27th ed)
  • Pregnancy Complications, Neoplastic [M0017478]
    The co-occurrence of pregnancy and NEOPLASMS. The neoplastic disease may precede or follow FERTILIZATION.
  • Preleukemia [M0017531]
    Conditions in which the abnormalities in the peripheral blood or bone marrow represent the early manifestations of acute leukemia, but in which the changes are not of sufficient magnitude or specificity to permit a diagnosis of acute leukemia by the usual clinical criteria.
  • Primary Supratentorial Neoplasms [M0336215]
  • Prolactinoma [M0023326]
    A pituitary adenoma which secretes PROLACTIN, leading to HYPERPROLACTINEMIA. Clinical manifestations include AMENORRHEA; GALACTORRHEA; IMPOTENCE; HEADACHE; visual disturbances; and CEREBROSPINAL FLUID RHINORRHEA.
  • Proliferative Brenner Tumor [M0472445]
    Brenner tumor of borderline malignancy.
  • Prostate Cancer [M0017834]
  • Prostatic Intraepithelial Neoplasia [M0028438]
    A premalignant change arising in the prostatic epithelium, regarded as the most important and most likely precursor of prostatic adenocarcinoma. The neoplasia takes the form of an intra-acinar or ductal proliferation of secretory cells with unequivocal nuclear anaplasia, which corresponds to nuclear grade 2 and 3 invasive prostate cancer.
  • Prostatic Neoplasms [M0017833]
    Tumors or cancer of the PROSTATE.
  • Proteus Syndrome [M0025456]
    Hamartoneoplastic malformation syndrome of uncertain etiology characterized by partial gigantism of the hands and/or feet, asymmetry of the limbs, plantar hyperplasia, hemangiomas, lipomas, lymphangiomas, epidermal nevi, macrocephaly, cranial hyperostoses, and long-bone overgrowth. Joseph Merrick, the so-called "elephant man", apparently suffered from Proteus syndrome and not neurofibromatosis, a disorder with similar characteristics.
  • Psammomatous Meningioma [M0337839]
  • Pseudomyxoma Peritonei [M0017956]
    A condition characterized by poorly-circumscribed gelatinous masses filled with malignant mucin-secreting cells. Forty-five percent of pseudomyxomas arise from the ovary, usually in a mucinous cystadenocarcinoma (CYSTADENOCARCINOMA, MUCINOUS), which has prognostic significance. Pseudomyxoma peritonei must be differentiated from mucinous spillage into the peritoneum by a benign mucocele of the appendix. (Segen, Dictionary of Modern Medicine, 1992)
  • Pulmonary Blastoma [M0027431]
    A malignant neoplasm of the lung composed chiefly or entirely of immature undifferentiated cells (i.e., blast forms) with little or virtually no stroma. (From Stedman, 25th ed)
  • Pulmonary Sclerosing Hemangioma [M0459911]
    A benign neoplasm of alveolar pneumocytes or ontogenetically primitive counterparts thereof. Morphological patterns that have been described include: solid, hemorrhagic, papillary, and sclerotic. Most lesions display a combination of two or three morphological patterns. Despite the implication by its name (HEMANGIOMA) of a vascular neoplasm, pulmonary sclerosing hemangioma is considered by most authorities to be an epithelial tumor. (Histopathology 2003;43(3):239-43; Arch Pathol Lab Med. 2001;125(10): 1335-9)
  • Radiation-Induced Cancer [M0333132]
  • Rathke Cleft Cysts [M0336762]
  • Rectal Neoplasms [M0018657]
    Tumors or cancer of the RECTUM.
  • Rectal Tumors [M0448728]
  • Residual Cancer [M0027592]
  • Residual Tumor [M0027594]
  • Respiratory Tract Neoplasms [M0018921]
  • Reticuloendotheliosis [M0018936]
    Hyperplasia of reticuloendothelial tissue, in any organ or tissue. A related concept is reticulosis which is an increase in reticuloendothelial elements.
  • Reticulohistiocytoma [M0023961]
  • Reticulosis [M0018937]
  • Retinal Cancer [M0468083]
  • Retinal Neoplasms [M0029062]
    Tumors or cancer of the RETINA.
  • Retinoblastoma [M0018961]
    A malignant tumor arising from the nuclear layer of the retina that is the most common primary tumor of the eye in children. The tumor tends to occur in early childhood or infancy and may be present at birth. The majority are sporadic, but the condition may be transmitted as an autosomal dominant trait. Histologic features include dense cellularity, small round polygonal cells, and areas of calcification and necrosis. An abnormal pupil reflex (leukokoria); NYSTAGMUS, PATHOLOGIC; STRABISMUS; and visual loss represent common clinical characteristics of this condition. (From DeVita et al., Cancer: Principles and Practice of Oncology, 5th ed, p2104)
  • Retroperitoneal Neoplasms [M0018975]
  • Rhabdoid Tumor [M0027572]
    A rare but highly lethal childhood tumor found almost exclusively in infants. Histopathologically, it resembles RHABDOMYOSARCOMA but the tumor cells are not of myogenic origin. Although it arises primarily in the kidney, it may be found in other parts of the body. The rhabdoid cytomorphology is believed to be the expression of a very primitive malignant cell. (From Holland et al., Cancer Medicine, 3d ed, p2210)
  • Rhabdomyoma [M0019000]
    A benign tumor derived from striated muscle. It is extremely rare, generally occurring in the tongue, neck muscles, larynx, uvula, nasal cavity, axilla, vulva, and heart. These tumors are treated by simple excision. (Dorland, 27th ed; DeVita Jr et al., Cancer: Principles & Practice of Oncology, 3d ed, p1354)
  • Rhabdomyosarcoma [M0019001]
    A malignant solid tumor arising from mesenchymal tissues which normally differentiate to form striated muscle. It can occur in a wide variety of sites. It is divided into four distinct types: pleomorphic, predominantly in male adults; alveolar (RHABDOMYOSARCOMA, ALVEOLAR), mainly in adolescents and young adults; embryonal (RHABDOMYOSARCOMA, EMBRYONAL), predominantly in infants and children; and botryoidal, also in young children. It is one of the most frequently occurring soft tissue sarcomas and the most common in children under 15. (From Dorland, 27th ed; Holland et al., Cancer Medicine, 3d ed, p2186; DeVita Jr et al., Cancer: Principles & Practice of Oncology, 3d ed, pp1647-9)
  • Rhabdomyosarcoma, Alveolar [M0027461]
    A form of RHABDOMYOSARCOMA occurring mainly in adolescents and young adults, affecting muscles of the extremities, trunk, orbital region, etc. It is extremely malignant, metastasizing widely at an early stage. Few cures have been achieved and the prognosis is poor. "Alveolar" refers to its microscopic appearance simulating the cells of the respiratory alveolus. (Holland et al., Cancer Medicine, 3d ed, p2188)
  • Rhabdomyosarcoma, Embryonal [M0027462]
    A form of RHABDOMYOSARCOMA arising primarily in the head and neck, especially the orbit, of children below the age of 10. The cells are smaller than those of other rhabdomyosarcomas and are of two basic cell types: spindle cells and round cells. This cancer is highly sensitive to chemotherapy and has a high cure rate with multi-modality therapy. (From Holland et al., Cancer Medicine, 3d ed, p2188)
  • Rous Sarcoma [M0002033]
  • Sacromatoid Renal Cell Carcinoma [M0484518]
  • Salivary Gland Neoplasms [M0019377]
    Tumors or cancer of the SALIVARY GLANDS.
  • Sarcoma [M0019428]
    A connective tissue neoplasm formed by proliferation of mesodermal cells; it is usually highly malignant.
  • Sarcoma 180 [M0019431]
  • Sarcoma 37 [M0019432]
  • Sarcoma, Alveolar Soft Part [M0027463]
    A variety of sarcoma having a reticulated fibrous stroma enclosing groups of sarcoma cells, which resemble epithelial cells and are enclosed in alveoli walled with connective tissue. It is a rare tumor, usually occurring between 15 and 35 years of age. It appears in the muscles of the extremities in adults and most commonly in the head and neck region of children. Though slow-growing, it commonly metastasizes to the lungs, brain, bones, and lymph nodes. (From Dorland, 27th ed; DeVita Jr et al., Cancer: Principles & Practice of Oncology, 3d ed, p1365)
  • Sarcoma, Avian [M0002032]
    Connective tissue tumors, affecting primarily fowl, that are usually caused by avian sarcoma viruses.
  • Sarcoma, Clear Cell [M0027456]
    A sarcoma of young, often female, adults of the lower extremities and acral regions, intimately bound to tendons as circumscribed but unencapsulated melanin-bearing tumors of neuroectodermal origin. An ultrastructural finding simulates flattened and curved barrel staves, corresponding to the internal structures of premelanosomes. There is a 45-60% mortality in clear cell sarcoma. (Segen, Dictionary of Modern Medicine, 1992)
  • Sarcoma, Endometrial Stromal [M0027432]
    A highly malignant subset of neoplasms arising from the endometrial stroma. Tumors in this group infiltrate the stroma with a wide range of atypia cells and numerous mitoses. They are capable of widespread metastases (NEOPLASM METASTASIS).
  • Sarcoma, Endometrial Stromal, Low-Grade [M0413810]
  • Sarcoma, Engelbreth-Holm-Swarm [M0019434]
  • Sarcoma, Epithelioid [M0019429]
  • Sarcoma, Ewing's [M0019433]
    A malignant tumor of the bone which always arises in the medullary tissue, occurring more often in cylindrical bones. There are conspicuous foci of necrosis in association with irregular masses of small, regular, rounded or ovoid cells with very scanty cytoplasm. The tumor occurs usually before the age of 20, about twice as frequently in males as in females. (From Dorland, 27th ed; Stedman, 25th ed)
  • Sarcoma, Experimental [M0019435]
    Experimentally induced neoplasms of CONNECTIVE TISSUE in animals to provide a model for studying human SARCOMA.
  • Sarcoma, Granulocytic [M0369140]
    An extramedullary tumor of immature myeloid cells. Granulocytic sarcoma usually occurs with or follows the onset of acute myeloid leukemia (LEUKEMIA, MYELOCYTIC, ACUTE).
  • Sarcoma, Jensen [M0019436]
  • Sarcoma, Kaposi [M0019437]
    A multicentric, malignant neoplastic vascular proliferation characterized by the development of bluish-red cutaneous nodules, usually on the lower extremities, most often on the toes or feet, and slowly increasing in size and number and spreading to more proximal areas. The tumors have endothelium-lined channels and vascular spaces admixed with variably sized aggregates of spindle-shaped cells, and often remain confined to the skin and subcutaneous tissue, but widespread visceral involvement may occur. Kaposi's sarcoma occurs spontaneously in Jewish and Italian males in Europe and the United States. An aggressive variant in young children is endemic in some areas of Africa. A third form occurs in about 0.04% of kidney transplant patients. There is also a high incidence in AIDS patients. (From Dorland, 27th ed & Holland et al., Cancer Medicine, 3d ed, pp2105-7) HHV-8 is the suspected cause.
  • Sarcoma, Small Cell [M0027457]
    A sarcoma characterized by the presence of small cells, cells measuring 9-14 micrometers with a faint or indistinct rim of cytoplasm and an oval-to-elongated nucleus with relatively dense chromatin. (From Segen, Dictionary of Modern Medicine, 1992)
  • Sarcoma, Spindle Cell [M0019430]
  • Sarcoma, Synovial [M0020963]
    A malignant neoplasm arising from tenosynovial tissue of the joints and in synovial cells of tendons and bursae. The legs are the most common site, but the tumor can occur in the abdominal wall and other trunk muscles. There are two recognized types: the monophasic (characterized by sheaths of monotonous spindle cells) and the biphasic (characterized by slit-like spaces or clefts within the tumor, lined by cuboidal or tall columnar epithelial cells). These sarcomas occur most commonly in the second and fourth decades of life. (From Dorland, 27th ed; DeVita Jr et al., Cancer: Principles & Practice of Oncology, 3d ed, p1363)
  • Sarcoma, Yoshida [M0019440]
  • Schwannoma, Acoustic, Bilateral [M0406513]
  • Schwannomatosis, Plexiform [M0336466]
  • Sebaceous Gland Neoplasms [M0019582]
  • Secretory Meningioma [M0337840]
  • Seminoma [M0027468]
    A radiosensitive, malignant neoplasm of the testis, thought to be derived from primordial germ cells of the sexually undifferentiated embryonic gonad. There are three variants: classical (typical), the most common type; anaplastic; and spermatocytic. The classical seminoma is composed of fairly well differentiated sheets or cords of uniform polygonal or round cells (seminoma cells), each cell having abundant clear cytoplasm, distinct cell membranes, a centrally placed round nucleus, and one or more nucleoli. In the female, a grossly and histologically identical neoplasm, known as dysgerminoma, occurs. (Dorland, 27th ed)
  • Sertoli Cell Tumor [M0019690]
    Gonadal neoplasm composed entirely of SERTOLI CELLS or may have a component of GRANULOSA CELLS. Some of the Sertoli cell tumors produce ESTROGEN or ANDROGENS, but seldom in sufficient quantity to cause clinical symptoms such as FEMINIZATION or masculinization (VIRILISM).
  • Sertoli-Leydig Cell Tumor [M0027545]
    A sex cord-gonadal stromal tumor consists of LEYDIG CELLS; SERTOLI CELLS; and FIBROBLASTS in varying proportions and degree of differentiation. Most such tumors produce ANDROGENS in the Leydig cells, formerly known as androblastoma or arrhenoblastoma. Androblastomas occur in the TESTIS or the OVARY causing precocious masculinization in the males, and defeminization, or virilization (VIRILISM) in the females. In some cases, the Sertoli cells produce ESTROGENS.
  • Sex Cord-Gonadal Stromal Tumors [M0027547]
    Neoplasms derived from the primitive sex cord or gonadal stromal cells of the embryonic GONADS. They are classified by their presumed histogenesis and differentiation. From the sex cord, there are SERTOLI CELL TUMOR and GRANULOSA CELL TUMOR; from the gonadal stroma, LEYDIG CELL TUMOR and THECOMA. These tumors may be identified in either the OVARY or the TESTIS.
  • Sezary Syndrome [M0019760]
    A form of cutaneous T-cell lymphoma manifested by generalized exfoliative erythroderma, intense pruritus, peripheral lymphadenopathy, and abnormal hyperchromatic mononuclear cells in the skin, lymph nodes, and peripheral blood (Sezary cells). (Dorland, 27th ed)
  • Sigmoid Cancer [M0333403]
  • Sigmoid Neoplasms [M0019837]
    Tumors or cancer of the SIGMOID COLON.
  • Skin Neoplasms [M0019939]
    Tumors or cancer of the SKIN.
  • Skull Base Neoplasms [M0028724]
    Neoplasms of the base of the skull specifically, differentiated from neoplasms of unspecified sites or bones of the skull (SKULL NEOPLASMS).
  • Skull Neoplasms [M0019950]
    Neoplasms of the bony part of the skull.
  • Smooth Muscle Tumor [M0027464]
    A tumor composed of smooth muscle tissue, as opposed to leiomyoma, a tumor derived from smooth muscle.
  • Soft Tissue Neoplasms [M0020121]
    Neoplasms of whatever cell type or origin, occurring in the extraskeletal connective tissue framework of the body including the organs of locomotion and their various component structures, such as nerves, blood vessels, lymphatics, etc.
  • Somatostatinoma [M0020155]
    A SOMATOSTATIN-secreting tumor derived from the pancreatic delta cells (SOMATOSTATIN-SECRETING CELLS). It is also found in the INTESTINE. Somatostatinomas are associated with DIABETES MELLITUS; CHOLELITHIASIS; STEATORRHEA; and HYPOCHLORHYDRIA. The majority of somatostatinomas have the potential for METASTASIS.
  • Sphenoid Wing Meningioma [M0481063]
  • Spinal Cord Neoplasms [M0020313]
    Benign and malignant neoplasms which occur within the substance of the spinal cord (intramedullary neoplasms) or in the space between the dura and spinal cord (intradural extramedullary neoplasms). The majority of intramedullary spinal tumors are primary CNS neoplasms including ASTROCYTOMA; EPENDYMOMA; and LIPOMA. Intramedullary neoplasms are often associated with SYRINGOMYELIA. The most frequent histologic types of intradural-extramedullary tumors are MENINGIOMA and NEUROFIBROMA.
  • Spinal Cord Neoplasms, Benign [M0336105]
  • Spinal Cord Neoplasms, Malignant [M0336106]
  • Spinal Meningeal Neoplasms [M0337066]
  • Spinal Meningioma [M0481059]
  • Spinal Neoplasms [M0020320]
  • Splenic Neoplasms [M0020370]
    Tumors or cancer of the SPLEEN.
  • Spongioblastoma [M0337491]
  • Spongioblastoma, Polar [M0336849]
  • Sporadic Retinoblastoma [M0336986]
  • Squamous Cell Cancer [M0333144]
  • Stomach Neoplasms [M0020544]
    Tumors or cancer of the STOMACH.
  • Struma Ovarii [M0020626]
    A rare teratoid tumor of the ovary composed almost entirely of thyroid tissue, with large follicles containing abundant colloid. Occasionally there are symptoms of hyperthyroidism. 5-10% of struma ovarii become malignant, the only absolute criterion for which is the presence of metastasis. (Dorland, 27th ed; Segen, Dictionary of Modern Medicine, 1992)
  • Sturge-Weber Syndrome [M0020641]
    A congenital syndrome characterized by a port-wine nevus covering portions of the face and cranium (in the distribution of the ophthalmic division of the TRIGEMINAL NERVE) and angiomas of the meninges and choroid. Clinical manifestations include the onset of focal SEIZURES, progressive hemiparesis, GLAUCOMA, hemianopsia, and cognitive deficits in the first decade of life. By age two years, skull radiographs reveal "tramline calcifications" of the margins of the occipital and parietal lobes. Pathologically cortical neurons are replaced by glial tissue that undergoes calcification. (From Adams et al., Principles of Neurology, 6th ed, pp1018-9)
  • Subependymal Astrocytoma, Adult [M0337426]
  • Subependymal Gliosis [M0337427]
  • Sublingual Gland Neoplasms [M0020665]
    Neoplasms of the sublingual glands.
  • Submandibular Gland Neoplasms [M0020668]
  • Supratentorial Neoplasms [M0023322]
    Primary and metastatic (secondary) tumors of the brain located above the tentorium cerebelli, a fold of dura mater separating the CEREBELLUM and BRAIN STEM from the cerebral hemispheres and DIENCEPHALON (i.e., THALAMUS and HYPOTHALAMUS and related structures). In adults, primary neoplasms tend to arise in the supratentorial compartment, whereas in children they occur more frequently in the infratentorial space. Clinical manifestations vary with the location of the lesion, but SEIZURES; APHASIA; HEMIANOPSIA; hemiparesis; and sensory deficits are relatively common features. Metastatic supratentorial neoplasms are frequently multiple at the time of presentation.
  • Sweat Gland Neoplasms [M0020921]
  • Syringoma [M0027481]
    A benign tumor of the sweat glands which is usually multiple and results from malformation of sweat ducts. It is uncommon and more common in females than in males. It is most likely to appear at adolescence, and further lesions may develop during adult life. It does not appear to be hereditary. (Rook et al., Textbook of Dermatology, 4th ed, pp2407-8)
  • Teratocarcinoma [M0027472]
    A malignant neoplasm consisting of elements of teratoma with those of embryonal carcinoma or choriocarcinoma, or both. It occurs most often in the testis. (Dorland, 27th ed)
  • Teratoma [M0021174]
    A true neoplasm composed of a number of different types of tissue, none of which is native to the area in which it occurs. It is composed of tissues that are derived from three germinal layers, the endoderm, mesoderm, and ectoderm. They may be solid or cystic and are classified histologically as mature, immature, and malignant. (From Dorland, 27th ed & DeVita Jr et al., Cancer: Principles & Practice of Oncology, 3d ed, p1642)
  • Testicular Neoplasms [M0021192]
    Tumors or cancer of the TESTIS. Germ cell tumors (GERMINOMA) of the testis constitute 95% of all testicular neoplasms.
  • Thecoma [M0021273]
    A gonadal stromal neoplasm composed only of THECA CELLS, occurring mostly in the postmenopausal OVARY. It is filled with lipid-containing spindle cells and produces ESTROGENS that can lead to ENDOMETRIAL HYPERPLASIA; UTERINE HEMORRHAGE; or other malignancies in postmenopausal women and sexual precocity in girls. When tumors containing theca cells also contain FIBROBLASTS, they are identified as thecoma-fibroma tumors with less active hormone production.
  • Therapy-Associated Cancer [M0333143]
  • Thoracic Neoplasms [M0021397]
  • Thymoma [M0021459]
    A neoplasm originating from thymic tissue, usually benign, and frequently encapsulated. Although it is occasionally invasive, metastases are extremely rare. It consists of any type of thymic epithelial cell as well as lymphocytes that are usually abundant and probably not neoplastic. Malignant lymphomas that involve the thymus, e.g., lymphosarcoma, Hodgkin's disease (previously termed granulomatous thymoma), should not be regarded as thymoma. (Stedman, 25th ed)
  • Thymus Neoplasms [M0021471]
    Tumors or cancer of the THYMUS GLAND.
  • Thyroid Adenoma [M0471769]
  • Thyroid Carcinoma [M0333546]
  • Thyroid Neoplasms [M0021485]
    Tumors or cancer of the THYROID GLAND.
  • Thyroid Nodule [M0025323]
    A small circumscribed mass in the THYROID GLAND that can be of neoplastic growth or non-neoplastic abnormality. It lacks a well-defined capsule or glandular architecture. Thyroid nodules are often benign but can be malignant. The growth of nodules can lead to a multinodular goiter (GOITER, NODULAR).
  • Tongue Neoplasms [M0021659]
    Tumors or cancer of the TONGUE.
  • Tonsillar Neoplasms [M0021664]
    Tumors or cancer of the TONSIL.
  • Tracheal Neoplasms [M0021745]
  • Transitional Meningioma [M0337841]
  • Trophoblastic Cancer [M0333626]
  • Trophoblastic Neoplasms [M0022033]
    Trophoblastic growth, which may be gestational or nongestational in origin. Trophoblastic neoplasia resulting from pregnancy is often described as gestational trophoblastic disease to distinguish it from germ cell tumors which frequently show trophoblastic elements, and from the trophoblastic differentiation which sometimes occurs in a wide variety of epithelial cancers. Gestational trophoblastic growth has several forms, including HYDATIDIFORM MOLE and CHORIOCARCINOMA. (From Holland et al., Cancer Medicine, 3d ed, p1691)
  • Trophoblastic Tumor, Placental Site [M0027474]
    An uncommon variant of CHORIOCARCINOMA. It is composed almost entirely of mononuclear cytotrophoblasts (TROPHOBLASTS). Because its secretion of hCG (CHORIONIC GONADOTROPIN) is low, a large tumor may develop before the hCG can be detected.
  • Tuberous Sclerosis [M0022136]
    An autosomal dominant disorder which is generally classified as a phacomatosis. Pathologically, the condition is characterized by glial cell tumors which arise in the cerebral hemispheres and retina. There is an increased incidence of benign rhabdomyomas of the heart and angiomyolipomas of kidney, liver, lungs, thyroid, and testes. Clinical manifestations include MENTAL RETARDATION; adenoma sebaceum of the face (actually angiofibromas); EPILEPSY; SPASMS, INFANTILE; Shagreen patches on the trunk; and subungual fibromas. (From Adams et al., Principles of Neurology, 6th ed, p1011)
  • Tumor of Rete Testis [M0021191]
  • Tumor Virus Infections [M0022156]
    Infections produced by oncogenic viruses. The infections caused by DNA viruses are less numerous but more diverse than those caused by the RNA oncogenic viruses.
  • Unknown Primary Tumors [M0014609]
  • Upper Aerodigestive Tract Neoplasms [M0358107]
  • Ureteral Neoplasms [M0022326]
    Cancer or tumors of the URETER which may cause obstruction leading to hydroureter, HYDRONEPHROSIS, and PYELONEPHRITIS. HEMATURIA is a common symptom.
  • Urethral Neoplasms [M0022333]
    Cancer or tumors of the URETHRA. Benign epithelial tumors of the urethra usually consist of squamous and transitional cells. Primary urethral carcinomas are rare and typically of squamous cells. Urethral carcinoma is the only urological malignancy that is more common in females than in males.
  • Urinary Bladder Cancer [M0332202]
  • Urinary Bladder Neoplasms [M0002635]
    Tumors or cancer of the URINARY BLADDER.
  • Urogenital Neoplasms [M0022391]
    Tumors or cancer of the UROGENITAL SYSTEM in either the male or the female.
  • Urologic Neoplasms [M0022401]
    Tumors or cancer of the URINARY TRACT in either the male or the female.
  • Uterine Cervical Dysplasia [M0003937]
    Abnormal development of immature squamous EPITHELIAL CELLS of the UTERINE CERVIX, a term used to describe premalignant cytological changes in the cervical EPITHELIUM. These atypical cells do not penetrate the epithelial BASEMENT MEMBRANE.
  • Uterine Cervical Neoplasms [M0003944]
    Tumors or cancer of the UTERINE CERVIX.
  • Uterine Neoplasms [M0022431]
    Tumors or cancer of the UTERUS.
  • Uveal Neoplasms [M0022444]
    Tumors or cancer of the UVEA.
  • Vaginal Cancer [M0022484]
  • Vaginal Neoplasms [M0022485]
    Tumors or cancer of the VAGINA.
  • Vascular Neoplasms [M0028432]
    Neoplasms located in vascular tissue or specific veins. They are differentiated from NEOPLASMS, VASCULAR TISSUE which are neoplasms composed of vascular tissue, such as ANGIOFIBROMA or HEMANGIOMA.
  • Venereal Tumors, Veterinary [M0022587]
    Tumors most commonly seen on or near the genitalia. They are venereal, most likely transmitted through transplantation of cells by contact. Metastases have been reported. Spontaneous regression may occur.
  • Vipoma [M0006214]
    A tumor that secretes VASOACTIVE INTESTINAL PEPTIDE, a neuropeptide that causes VASODILATION; relaxation of smooth muscles; watery DIARRHEA; HYPOKALEMIA; and HYPOCHLORHYDRIA. Vipomas, derived from the pancreatic ISLET CELLS, generally are malignant and can secrete other hormones. In most cases, Vipomas are located in the PANCREAS but can be found in extrapancreatic sites.
  • Vulvar Neoplasms [M0022857]
    Tumors or cancer of the VULVA.
  • WAGR Syndrome [M0026692]
    A contiguous gene syndrome associated with hemizygous deletions of chromosome region 11p13. The condition is marked by the combination of WILMS TUMOR; ANIRIDIA; GENITOURINARY ABNORMALITIES; and MENTAL RETARDATION.
  • Waldenstrom Macroglobulinemia [M0012865]
    A plasma cell dyscrasia resembling leukemia with cells of lymphocytic, plasmacytic, or intermediate morphology, which secrete an IMMUNOGLOBULIN M monoclonal component. There is diffuse infiltration of bone marrow and also, in many cases, of the spleen, liver, or lymph nodes. The circulating macroglobulin produces symptoms of hyperviscosity syndrome: weakness, fatigue, bleeding disorders, and visual disturbances. Peak incidence is in the sixth and seventh decades. (Dorland, 28th ed)
  • Wilms Tumor [M0014630]
    A malignant kidney tumor, caused by the uncontrolled multiplication of renal stem (blastemal), stromal (STROMAL CELLS), and epithelial (EPITHELIAL CELLS) elements. However, not all three are present in every case. Several genes or chromosomal areas have been associated with Wilms tumor which is usually found in childhood as a firm lump in a child's side or ABDOMEN.
  • Xanthomatous Meningioma [M0337842]
  • Xeroderma Pigmentosum [M0023063]
    A rare, pigmentary, and atrophic autosomal recessive disease. It is manifested as an extreme photosensitivity to ULTRAVIOLET RAYS as the result of a deficiency in the enzyme that permits excisional repair of ultraviolet-damaged DNA.