| basal squamous cell carcinoma | <tumour> A carcinoma of the skin which in structure and behaviour is considered transitional between basal cell and squamous cell carcinoma The term should not be used for the much more common keratotic variety of basal cell carcinoma, in which the tumour cells are of basal type but which contains small foci of abrupt keratinization. Synonym: basal squamous cell carcinoma. (05 Mar 2000) |
|---|---|
| carcinoma, basal cell | 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. (12 Dec 1998) |
| neoplasms, basal cell | Neoplasms composed of cells from the deepest layer of the epidermis. The concept does not refer to neoplasms located in the stratum basale. (12 Dec 1998) |
| nevoid basal cell carcinoma syndrome | <syndrome> An inherited group of defects which involve abnormalities of the skin, eyes, nervous system, endocrine, glands and bones. The condition is characterised by an unusual facial appearance and a predisposition for skin cancer. (27 Sep 1997) |
| acidophil adenoma | <endocrinology, oncology, tumour> A benign tumour, usually found in the anterior lobe of the pituitary gland, whose cells stain with acid dyes. Such pituitary tumours 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 galactorrhoea. (25 Jun 1999) |
| ACTH-producing adenoma | <tumour> A pituitary tumour composed of corticotrophs that produce ACTH, often a basophilic adenoma; may give rise to Cushing's disease or Nelson's syndrome. (05 Mar 2000) |
| adenoma | <oncology, tumour> A benign epithelial tumour in which the cells form recognisable glandular structures or in which the cells are clearly derived from glandular epithelium. (18 Nov 1997) |
| adenoma, adrenal cortical | A benign neoplasm of adrenal cortical cells resembling normal adrenal cells histologically but possessing functional autonomy. In general it does not exceed 5 cm in its largest dimension, although benign tumours exceeding 20 cm have been reported. Adrenal cortical adenomas produce hypercortisolism and hyperaldosteronism, but seldom produce adrenogenital syndromes. For the most part the prognosis after surgery is reasonably favourable. (12 Dec 1998) |
| adenoma, basophil | A small tumour 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's syndrome. (12 Dec 1998) |
| adenoma, bile duct | A benign tumour of the intrahepatic bile ducts. (12 Dec 1998) |
| adenoma, chromophobe | A tumour of the anterior lobe of the pituitary gland whose cells do not stain readily with either acid or basic dyes and whose presence may be associated with hypopituitarism. Although classically these adenomas have been said to be composed of sparsely granulated or degranulated (nonfunctioning) cells, some contain functioning cells and may be associated with a hyperpituitary state, e.g., acromegaly or cushing's syndrome. (12 Dec 1998) |
| adenoma fibrosum | <oncology, tumour> A benign solid growth, usually found in the breast. (09 Oct 1997) |
| adenoma of nipple | A benign tumour which may clinically resemble Paget's disease, but which is a papillary or solid growth of columnar and myoepithelial cells producing a florid pseudoinfiltrative pattern. Synonym: adenoma of nipple, erosive adenomatosis of nipple. (05 Mar 2000) |
| adenoma, oxyphilic | A usually benign adenoma composed of oncocytes with granular, eosinophilic cytoplasm due to the presence of abundant mitochondria. It is often composed of huerthle cells found in the thyroid. It occurs uncommonly in the kidney, salivary glands, and endocrine glands. (12 Dec 1998) |
| adenoma, pleomorphic | A benign, slow-growing tumour, 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 tumour presents a variety of cells: cuboidal, columnar, and squamous cells, showing all forms of epithelial growth. (12 Dec 1998) |