Biomaterial Database

Grades of atypia in tubular and villous adenomas of the human colon. An electron microscopic study. 1980

H Gabbert, and P Höhn

Of a total of 544 tubular, villous and tubulo-villous adenomas of the human colon which were investigated by light microscopy, six tubular and six villous adenomas were examined under the electron microscope. It was shown that the two types of adenoma differ in their tissue architecture, but not in their cytological appearance. Different grades of epithelial atypia occur in both types of adenoma. These are designated as grades I to III, correspond to mild, moderate and severe atypia respectively. Whereas adenoma cells with atypia grade I clearly show a cytological relationship with crypt epithelia of the normal colonic mucosa under the electron microscope, adenoma cells with atypia grade III have largely lost the differentiation characteristics of the parent cells and there is no longer intracytoplasmic organization. In the cytoplasm of adenoma cells with atypia grade II, glycogen storage is found as a special feature which does not occur in normal colonic epithelium. A similar finding has been described in the course of malignant transformation of the liver and kidney and thus can be regarded as a further indication of the precancerous nature of the adenomas.

UI	MeSH Term	Description	Entries
D008854	Microscopy, Electron	Microscopy using an electron beam, instead of light, to visualize the sample, thereby allowing much greater magnification. The interactions of ELECTRONS with specimens are used to provide information about the fine structure of that specimen. In TRANSMISSION ELECTRON MICROSCOPY the reactions of the electrons that are transmitted through the specimen are imaged. In SCANNING ELECTRON MICROSCOPY an electron beam falls at a non-normal angle on the specimen and the image is derived from the reactions occurring above the plane of the specimen.	Electron Microscopy
D002454	Cell Differentiation	Progressive restriction of the developmental potential and increasing specialization of function that leads to the formation of specialized cells, tissues, and organs.	Differentiation, Cell,Cell Differentiations,Differentiations, Cell
D003110	Colonic Neoplasms	Tumors or cancer of the COLON.	Cancer of Colon,Colon Adenocarcinoma,Colon Cancer,Cancer of the Colon,Colon Neoplasms,Colonic Cancer,Neoplasms, Colonic,Adenocarcinoma, Colon,Adenocarcinomas, Colon,Cancer, Colon,Cancer, Colonic,Cancers, Colon,Cancers, Colonic,Colon Adenocarcinomas,Colon Cancers,Colon Neoplasm,Colonic Cancers,Colonic Neoplasm,Neoplasm, Colon,Neoplasm, Colonic,Neoplasms, Colon
D006003	Glycogen
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000236	Adenoma	A benign epithelial tumor with a glandular organization.	Adenoma, Basal Cell,Adenoma, Follicular,Adenoma, Microcystic,Adenoma, Monomorphic,Adenoma, Papillary,Adenoma, Trabecular,Adenomas,Adenomas, Basal Cell,Adenomas, Follicular,Adenomas, Microcystic,Adenomas, Monomorphic,Adenomas, Papillary,Adenomas, Trabecular,Basal Cell Adenoma,Basal Cell Adenomas,Follicular Adenoma,Follicular Adenomas,Microcystic Adenoma,Microcystic Adenomas,Monomorphic Adenoma,Monomorphic Adenomas,Papillary Adenoma,Papillary Adenomas,Trabecular Adenoma,Trabecular Adenomas