RISK-FACTORS AND P53 NUCLEAR OVEREXPRESSION IN EARLY-STAGE INTESTINAL-TYPE ADENOCARCINOMA OF THE STOMACH

In order to investigate the relationship between altered patterns of p 53 expression and risk factors for stomach cancer, we have analyzed a group of 35 patients with early stage intestinal-type adenocarcinoma o f the stomach. We assessed p53 nuclear overexpression by immunohistoch emistry, using monoclonal antibody PAb 1801, and identified 15 out of 35 patients (43%) displaying nuclear overexpression of p53 protein. Si gnificantly elevated odds ratios (O.R.) were observed for greater body mass index (highest quartile versus lowest quartile: O.R. = 7.9; 95% confidence interval (CI): 1.1 to 56.1) and younger age (< 60 vs. great er-than-or-equal-to 70 years: O.R. = 10; 95% CI, 1.43 to 50). The odds ratio for p53 overexpression in cigarette smokers was 2.8 (95% CI: 0. 7 to 11.6) but not statistically significant. These data indicate that p53 mutations may be involved in the early stages of gastric carcinog enesis, especially in the development of intestinal-type adenocarcinom a.