A Study of Nucleolar Organizer Regions in Normal and Neoplastic Epithelial Cells of Stomach

ABSTRACT

Nucleolar organizer regions are DNA loops encoding rihbosomal RNA production and detectable by the argyrophilia of their associated proteins(AgNORs). AgNOR numbers correlate with cellular proliferating activity. Many studies have shown a significnt difference in AgNOR counts between benign and malignant tumors. AgNOR counts were also helpful in differential diagnosis. For the evaluation of its diagnostic utility in gastric lesions, a silver staining technique was carried out in paraffin sections of 5 control cases, 5 benign peptic ulcers, 7 hyperplastic polyps, 10 tubular adenomas, 16 early gastric adenocarcinomas and 15 advanced gastric adenocarcinomas. The results were as follows. The mean numbers of AgNORs in early and advanced gastric adenocarcinomas(1.94 and 2.16) were significantly higher than those of normal foveolar epithelium(1.43) and epithelia of benign gastric ulcers(1.54), hyperplastic polyps(1.64) and tubular adenomas(1.79). In malignancy, there was increased variability in size and shape of AgNORs. There was little differences in mean AgNOR numbers between early and advanced gastric adenocarcinomas. Differentiation of the tumor made no difference in AgNOR numbers. From the above results, the AgNORs count, if its morphologic change are taken into consideration, is helpful in differentiation between malignant and non-malignant lesions.