RESUMO
There is increasing evidence that genes involved in normal cell growth and differentiation (oncogenes) or genes that encode for growth factors are important in determining the development and biologic aggressiveness of gastric carcinoma. This study was undertaken to define the prognostic value of the overexpression of p53 protein, c-erbB-2 protein, EGFr protein and PCNA in gastric carcinomas. Using monoclonal antibodies, immunohistochemical studies were performed on formalin-fixed, paraffin-embedded tissue sections from 84 primary gastric carcinomas. Overall, 34% of gastric carcinomas had nuclear-staining for p53 protein, 34% of carcinomas membrane staining for the c-erbB-2 and 74% of carcinomas membrane and cytoplasmic staining for EGFr, showing distribution in a heterogeneous fashion. PCNA was expressed as Grade 2 and 3 in 75% of patients with gastric carcinomas. Both c-erbB-2 and p53 staining was significantly associated with high grade expression of PCNA. p53 staining tended to be associated with positive nodal status and metastasis, and c-erbB-2 staining with positive nodal status only. Multivariate analysis using the Cox model showed that overexpression of p53 protein, c-erbB-2 protein and PCNA was not an independent prognostic variable in gastric carcinoma. These results suggest that expressions of p53 and c-erbB-2 protein are heterogeneous and that p53 and c-erbB-2 overexpressions are significantly associated with high proliferative activity in gastric carcinoma.