Study of nucleolar organizer regions (NORs) in lesions of gallbladder.

Tissue sections from 100 specimens of gallbladder including 40 cases of chronic cholecystitis, 30 cases of epithelial hyperplasia and 30 cases of well, moderately and poorly differentiated adenocarcinoma of gallbladder were studied for argyrophillic nucleolar organizer regions (AgNORs). The arithmetic mean +/- S.D. were calculated for each category. This showed NOR counts of chronic cholecystitis--(1.89+/-0.96), epithelial hyperplasia--(3.99+/-1.03), well differentiated adenocarcinoma (WDCA)--(7.04+/-1.34), moderately differentiated adenocarcinoma (MDCA)--(7.52+/-0.97) and poorly differentiated adenocarcinoma (PDCA)--(8.37+/-1.27). The study revealed increasing number of AgNORS from cases of chronic cholecystitis to epithelial hyperplasia to carcinoma gallbladder, but a considerable overlap in AgNOR counts of individual cases was observed suggesting that though AgNOR count cannot act as a specific diagnostic parameter for diagnosis of early carcinoma & dysplasia in isolated cases, they may prove to be a good adjunct to presently available imaging techniques and cytology.