BACKGROUND: Little is known about the changes in the immunohistochemical and histochemical characteristics that take place during the malignant transformation of gastric adenoma (GA). METHODS: Nine patients with GA who developed carcinoma (Group A) and 33 who did not (Group B) during an equivalent follow-up period (mean, 76.4 months; range, 38-166 months) were studied. Tissue sections from these patients were stained for p53, c-erbB-2, bcl-2, carbohydrate antigen 19-9 (CA 19-9), carcinoembryonic antigen (CEA), and proliferating cell nuclear antigen (PCNA), and by high iron diamine-alcian blue staining. The gastric or intestinal phenotypes of the GA cells were evaluated histochemically by paradoxical concanavalin A and galactose oxidase-Schiff reactions. RESULTS: In Group A, the following were more frequent; severe dysplasia (77.8% vs. 0%, P < 0.001), villous structures (66.7% vs. 9.1%, P < 0.05), sulfomucin secretion (88.9% vs. 39.4%, P < 0.05) and mixed gastric-intestinal phenotype (77.8% vs. 9.1%, P < 0.001). The development of carcinoma in Group A positively correlated with an increase in p53 expression and PCNA-labeling index. None of the adenomas was positive for c-erbB-2, but four of nine carcinomas showed positive reactions. CONCLUSIONS: Mucin histochemistry of GA may be of some value in assessing the potential for subsequent carcinoma. Immunoexpression of c-erbB-2, bcl-2, CA 19-9, and CEA have only limited value. In contrast to p53, the immunoexpression of c-erbB-2 is a late event in the malignant transformation of GA.
BACKGROUND: Little is known about the changes in the immunohistochemical and histochemical characteristics that take place during the malignant transformation of gastric adenoma (GA). METHODS: Nine patients with GA who developed carcinoma (Group A) and 33 who did not (Group B) during an equivalent follow-up period (mean, 76.4 months; range, 38-166 months) were studied. Tissue sections from these patients were stained for p53, c-erbB-2, bcl-2, carbohydrate antigen 19-9 (CA 19-9), carcinoembryonic antigen (CEA), and proliferating cell nuclear antigen (PCNA), and by high iron diamine-alcian blue staining. The gastric or intestinal phenotypes of the GA cells were evaluated histochemically by paradoxical concanavalin A and galactose oxidase-Schiff reactions. RESULTS: In Group A, the following were more frequent; severe dysplasia (77.8% vs. 0%, P < 0.001), villous structures (66.7% vs. 9.1%, P < 0.05), sulfomucin secretion (88.9% vs. 39.4%, P < 0.05) and mixed gastric-intestinal phenotype (77.8% vs. 9.1%, P < 0.001). The development of carcinoma in Group A positively correlated with an increase in p53 expression and PCNA-labeling index. None of the adenomas was positive for c-erbB-2, but four of nine carcinomas showed positive reactions. CONCLUSIONS: Mucin histochemistry of GA may be of some value in assessing the potential for subsequent carcinoma. Immunoexpression of c-erbB-2, bcl-2, CA 19-9, and CEA have only limited value. In contrast to p53, the immunoexpression of c-erbB-2 is a late event in the malignant transformation of GA.