Correlation between Familial Clustering of Malignant Neoplasms and Expression of the p53 Protein in Gastric Cancer

Abstract

The purpose of this study was to determine the correlation between familial clustering of malignant neoplasms and expression of the p53 protein in gastric cancer. We made a survey of the family history of malignant neoplasms in 342 patients who underwent resections for gastric cancer from 1989 to 1993. Twenty-two patients had two or more first degree relatives with malignant neoplasms. They were divided into two groups: Group A consisting of 10 patients with two or more first degree relatives with gastric cancer, and Group B consisting of 12 patients with one or no first degree relative with gastric cancer. Two hundred and thirty-nine patients who had no relatives with any malignant neoplasms were used as the control group. There were no significant differences in the clinicopathologic features among the three groups. Formalin-fixed paraffin-embedded specimens of the tumor were stained immunohistochemically for the p53 protein and proliferating cell nuclear antigen (PCNA). Staining for the p53 protein was positive in 80% of the patients in Group A, 75% in Group B and 38% in the controlgroup. There were statistically significant differences between Group A and the control group and between Group B and the control group (p<0.01). We could not find any difference in the PCNA labeling index among the three groups. In conclusion, immunohistochemical staining for the p53 protein of the tumor tissue in patients with gastric cancer may be useful for detecting the risk for malignant neoplasms in their families.