AMPLIFICATION OF EPIDERMAL GROWTH-FACTOR RECEPTOR GENE AND ITS RELATIONSHIP TO SURVIVAL IN HUMAN GASTRIC-CANCER

The correlation between the clinical features in 103 patients with pri mary gastric carcinoma and amplification of epidermal growth factor re ceptor (EGFR) gene was analyzed retrospectively. EGFR gene amplificati on was examined by slot-blot hybridization using DNA extracted from fo rmalin-fixed, paraffinembedded tissues. EGFR expression was also exami ned immunohistochemically using the same tissues with a monoclonal ant ibody that is monospecific for EGFR. In 5 to 103 cases (4.9%), a 2- to 11-fold amplification of EGFR gene was detected. Four of these 5 case s were poorly differentiated adenocarcinomas. All of them had overexpr essions of EGFR. The cumulative survival rate of patients with EGFR ge ne amplification was significantly lower than that of the patients wit hout amplification (p<0.05) and all of them died within 3 years. Excep t for tumor size (p<0.03), there were no significant clinicopathologic differences between the two groups. On the other hand, 41 of 103 case s (39.8%) exhibited expression of EGFR. However, there was no signific ant correlation between EGFR expression and clinicopathologic factors or prognosis. These results indicate that EGFR gene amplification may occur in advanced stages during the progression and be an important in dicator of poor short-term prognosis in gastric carcinoma.