Relationship of p53 and c-erbB-2 expression to histopathological features, Helicobacter pylori infection and prognosis in gastric cancer.
BACKGROUND/AIMS: Conflicting results concerning the relationships between abnormal expression of p53 and c-erbB-2 and biologic behavior of gastric cancer are noted. Therefore, overexpression of p53 and c-erbB-2 in relation to the following aspects of gastric cancer: tumor histopathology, Helicobacter pylori infection, and prognosis are explored. MATERIALS AND METHODS: Expression of p53 and c-erbB-2 by immunohistochemistry was correlated with histopathology, H. pylori infection and prognosis of gastric cancer in 112 patients. RESULTS: Positive p53 staining was found in 61 (54.5%) of 112 tumors examined. There was no association of p53 expression with sex, age, lymph node metastasis, H. pylori infection or prognosis. A significantly higher frequency of p53-positive staining was observed in advanced (60.7%), intestinal (69.8%) and cardia (76.5%) than in early (30.4%, p < 0.01), diffuse (34.7%, p < 0.01) and noncardia (50.5%, p < 0.05) carcinoma, respectively. Expression of c-erbB-2 was found in 34 cases (30.3%), and was not related to sex, age, H. pylori infection and tumor location. Tumors with positive c-erbB-2 staining appeared to behave more aggressively in view of higher rates of nodal metastasis (38.0% vs 17.1%, p < 0.05), advanced stage (37.1% vs 4.3%, p < 0.01) and poor mean survival (p < 0.01). Patients with intestinal type tumors also had a significantly higher rate of c-erbB-2 expression than those with diffuse tumors (39.7% vs 18.4%, p < 0.01). CONCLUSIONS: Our results indicate that immunohistochemical expressions of p53 and c-erbB-2 are significantly associated with some histopathological phenotypes. Genetic alterations of c-erbB-2 or p53 may not be affected by H. pylori infection. C-erbB-2 expression may be used as a marker for identifying more aggressive gastric cancer for designing further therapy.