Leydig Cell Tumor: 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.Leydig Cells: Steroid-producing cells in the interstitial tissue of the TESTIS. They are under the regulation of PITUITARY HORMONES; LUTEINIZING HORMONE; or interstitial cell-stimulating hormone. TESTOSTERONE is the major androgen (ANDROGENS) produced.Sertoli Cell Tumor: 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).Testicular Neoplasms: Tumors or cancer of the TESTIS. Germ cell tumors (GERMINOMA) of the testis constitute 95% of all testicular neoplasms.Sertoli-Leydig Cell Tumor: 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.Seminoma: 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)Testis: The male gonad containing two functional parts: the SEMINIFEROUS TUBULES for the production and transport of male germ cells (SPERMATOGENESIS) and the interstitial compartment containing LEYDIG CELLS that produce ANDROGENS.Diethylstilbestrol: A synthetic nonsteroidal estrogen used in the treatment of menopausal and postmenopausal disorders. It was also used formerly as a growth promoter in animals. According to the Fourth Annual Report on Carcinogens (NTP 85-002, 1985), diethylstilbestrol has been listed as a known carcinogen. (Merck, 11th ed)Testosterone: A potent androgenic steroid and major product secreted by the LEYDIG CELLS of the TESTIS. Its production is stimulated by LUTEINIZING HORMONE from the PITUITARY GLAND. In turn, testosterone exerts feedback control of the pituitary LH and FSH secretion. Depending on the tissues, testosterone can be further converted to DIHYDROTESTOSTERONE or ESTRADIOL.Granulosa Cell Tumor: 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.Giant Cell Tumor of Bone: 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)Dog Diseases: Diseases of the domestic dog (Canis familiaris). This term does not include diseases of wild dogs, WOLVES; FOXES; and other Canidae for which the heading CARNIVORA is used.Giant Cell Tumors: 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.Aromatase: An enzyme that catalyzes the desaturation (aromatization) of the ring A of C19 androgens and converts them to C18 estrogens. In this process, the 19-methyl is removed. This enzyme is membrane-bound, located in the endoplasmic reticulum of estrogen-producing cells of ovaries, placenta, testes, adipose, and brain tissues. Aromatase is encoded by the CYP19 gene, and functions in complex with NADPH-FERRIHEMOPROTEIN REDUCTASE in the cytochrome P-450 system.Neoplasms, Germ Cell and Embryonal: Neoplasms composed of primordial GERM CELLS of embryonic GONADS or of elements of the germ layers of the EMBRYO, MAMMALIAN. The concept does not refer to neoplasms located in the gonads or present in an embryo or FETUS.Neoplasms, Experimental: Experimentally induced new abnormal growth of TISSUES in animals to provide models for studying human neoplasms.Granular Cell Tumor: 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.Immunohistochemistry: Histochemical localization of immunoreactive substances using labeled antibodies as reagents.Germinoma: 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)Chorionic Gonadotropin: A gonadotropic glycoprotein hormone produced primarily by the PLACENTA. Similar to the pituitary LUTEINIZING HORMONE in structure and function, chorionic gonadotropin is involved in maintaining the CORPUS LUTEUM during pregnancy. CG consists of two noncovalently linked subunits, alpha and beta. Within a species, the alpha subunit is virtually identical to the alpha subunits of the three pituitary glycoprotein hormones (TSH, LH, and FSH), but the beta subunit is unique and confers its biological specificity (CHORIONIC GONADOTROPIN, BETA SUBUNIT, HUMAN).3-Hydroxysteroid Dehydrogenases: Catalyze the oxidation of 3-hydroxysteroids to 3-ketosteroids.Receptors, LH: Those protein complexes or molecular sites on the surfaces and cytoplasm of gonadal cells that bind luteinizing or chorionic gonadotropic hormones and thereby cause the gonadal cells to synthesize and secrete sex steroids. The hormone-receptor complex is internalized from the plasma membrane and initiates steroid synthesis.Luteinizing Hormone: A major gonadotropin secreted by the adenohypophysis (PITUITARY GLAND, ANTERIOR). Luteinizing hormone regulates steroid production by the interstitial cells of the TESTIS and the OVARY. The preovulatory LUTEINIZING HORMONE surge in females induces OVULATION, and subsequent LUTEINIZATION of the follicle. LUTEINIZING HORMONE consists of two noncovalently linked subunits, alpha and beta. Within a species, the alpha subunit is common in the three pituitary glycoprotein hormones (TSH, LH and FSH), but the beta subunit is unique and confers its biological specificity.Mesylates: Organic salts or esters of methanesulfonic acid.Sertoli Cells: Supporting cells projecting inward from the basement membrane of SEMINIFEROUS TUBULES. They surround and nourish the developing male germ cells and secrete ANDROGEN-BINDING PROTEIN and hormones such as ANTI-MULLERIAN HORMONE. The tight junctions of Sertoli cells with the SPERMATOGONIA and SPERMATOCYTES provide a BLOOD-TESTIS BARRIER.Sex Cord-Gonadal Stromal Tumors: 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.Pulmonary Blastoma: 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)Ovarian Neoplasms: 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.Cystadenoma: 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)Virilism: Development of male secondary SEX CHARACTERISTICS in the FEMALE. It is due to the effects of androgenic metabolites of precursors from endogenous or exogenous sources, such as ADRENAL GLANDS or therapeutic drugs.Adenylate Cyclase: An enzyme of the lyase class that catalyzes the formation of CYCLIC AMP and pyrophosphate from ATP. EC Esters: Tumor-promoting compounds obtained from CROTON OIL (Croton tiglium). Some of these are used in cell biological experiments as activators of protein kinase C.Guanylyl Imidodiphosphate: A non-hydrolyzable analog of GTP, in which the oxygen atom bridging the beta to the gamma phosphate is replaced by a nitrogen atom. It binds tightly to G-protein in the presence of Mg2+. The nucleotide is a potent stimulator of ADENYLYL CYCLASES.Tetradecanoylphorbol Acetate: A phorbol ester found in CROTON OIL with very effective tumor promoting activity. It stimulates the synthesis of both DNA and RNA.Cushing Syndrome: A condition caused by prolonged exposure to excess levels of cortisol (HYDROCORTISONE) or other GLUCOCORTICOIDS from endogenous or exogenous sources. It is characterized by upper body OBESITY; OSTEOPOROSIS; HYPERTENSION; DIABETES MELLITUS; HIRSUTISM; AMENORRHEA; and excess body fluid. Endogenous Cushing syndrome or spontaneous hypercortisolism is divided into two groups, those due to an excess of ADRENOCORTICOTROPIN and those that are ACTH-independent.Alopecia: Absence of hair from areas where it is normally present.Hirsutism: A condition observed in WOMEN and CHILDREN when there is excess coarse body hair of an adult male distribution pattern, such as facial and chest areas. It is the result of elevated ANDROGENS from the OVARIES, the ADRENAL GLANDS, or exogenous sources. The concept does not include HYPERTRICHOSIS, which is an androgen-independent excessive hair growth.Privacy: The state of being free from intrusion or disturbance in one's private life or affairs. (Random House Unabridged Dictionary, 2d ed, 1993)Confidentiality: The privacy of information and its protection against unauthorized disclosure.Computer Security: Protective measures against unauthorized access to or interference with computer operating systems, telecommunications, or data structures, especially the modification, deletion, destruction, or release of data in computers. It includes methods of forestalling interference by computer viruses or so-called computer hackers aiming to compromise stored data.Informed Consent: Voluntary authorization, by a patient or research subject, with full comprehension of the risks involved, for diagnostic or investigative procedures, and for medical and surgical treatment.Genetic Privacy: The protection of genetic information about an individual, family, or population group, from unauthorized disclosure.Internet: A loose confederation of computer communication networks around the world. The networks that make up the Internet are connected through several backbone networks. The Internet grew out of the US Government ARPAnet project and was designed to facilitate information exchange.Health Surveys: A systematic collection of factual data pertaining to health and disease in a human population within a given geographic area.Hoarseness: An unnaturally deep or rough quality of voice.Gastroenterology: A subspecialty of internal medicine concerned with the study of the physiology and diseases of the digestive system and related structures (esophagus, liver, gallbladder, and pancreas).Hospitals, Private: A class of hospitals that includes profit or not-for-profit hospitals that are controlled by a legal entity other than a government agency. (Hospital Administration Terminology, AHA, 2d ed)Menarche: The first MENSTRUAL CYCLE marked by the initiation of MENSTRUATION.Hair: A filament-like structure consisting of a shaft which projects to the surface of the SKIN from a root which is softer than the shaft and lodges in the cavity of a HAIR FOLLICLE. It is found on most surfaces of the body.Cell Proliferation: All of the processes involved in increasing CELL NUMBER including CELL DIVISION.Pregnenolone: A 21-carbon steroid, derived from CHOLESTEROL and found in steroid hormone-producing tissues. Pregnenolone is the precursor to GONADAL STEROID HORMONES and the adrenal CORTICOSTEROIDS.Receptors, Estrogen: Cytoplasmic proteins that bind estrogens and migrate to the nucleus where they regulate DNA transcription. Evaluation of the state of estrogen receptors in breast cancer patients has become clinically important.