[The usefulness of nucleolar organizer regions in diagnosis of colonic epithelial neoplasia].

The Ag-NORs technique, staining nucleolar organizer regions, was performed on 23 areas of colonic normal mucosa, 17 adenomas with low grade atypical and 8 adenocarcinoma invading submucosa, to examine its possibility of application to the pathological diagnosis of colonic epithelial neoplasia. In normal colonic gland, the average number of Ag-NORs per 1 nucleus in cells of lower two-thirds showed significantly higher value (p less than 0.01) than higher one-third, and the mean cross-section area per 1 Ag-NOR in lower two-thirds showed a tendency to be larger than higher one-third. This results suggested that there was a positive correlation between the proliferative activity of cells and the number and size of Ag-NORs. A comparison of normal gland, adenoma and adenocarcinoma showed that the mean cross-section area of Ag-NORs correlated positively to their histological grade of atypia, but the average number did not. However using these two parameters, these three lesions had a tendency to be discriminated respectively at the average Ag-NORs number of 2.8 dots and the area of 2 microns. These results suggested that the Ag-NORs technique was expected to be a useful method for histopathological diagnosis of colonic epithelial neoplasia.