title: Basal cell adenoma with acinic differentiation.
abstract: A case of basal cell adenoma in the left parotid region of a 45 years old male was reported. The tumor measured 1.1 cm X 0.9 cm, was spherical and covered with a fibrous capsule. Histologically, it was a monomorphic adenoma, forming solid, trabecular, tubular and acinic structure. The tumor cells secreted PAS-positive substance. Electron microscopically, the tumor consisted of three kinds of cells - secretory cells containing electron-dense secretory granules, non-secretory cells, and myoepithelial cells. The acinus was formed of single-layered secretory cells, in the base of which myoepithelial cells were observed. The tubulus was formed of both secretory and non-secretory cells, and myoepithelial cells were found in the base of the tubules. The interstitium was narrow, and was composed of a small amount of collagen fibers, myoepithelial cells, and basement membrane-like substance.
mesh_terms: D000236:Adenoma / Q000473:pathology* / Q000648:ultrastructure; D002454:Cell Differentiation; D003594:Cytoplasmic Granules / Q000648:ultrastructure; D003599:Cytoskeleton / Q000648:ultrastructure; D006056:Golgi Apparatus / Q000648:ultrastructure; D006801:Humans; D008297:Male; D008875:Middle Aged; D010307:Parotid Neoplasms / Q000473:pathology* / Q000648:ultrastructure