The purpose of this study is to obtain the clinicopathological characteristics of replication error-positive (RER ) gastric adenocarcinoma in Korean, and to identify the significance of RER in adenoma stage of gastric carcinogenesis. Microsatellite instability was examined at D2S71, D2S119, D3S1067, D6S87, D11S905, DM, AR, VWF, HPRT, and BAT-26 loci. Frameshift mutation of BAX gene was analyzed in RER tumors. Normal and tumor DNA of 76 cases of gastric carcinoma and 25 cases of adenoma were examined. RER was found in 8 of 76 cases (10.5%), and it was more frequently found in adenocarcinoma of female (17.7%) than those of male (4.8%).
The frequency of RER was not different between the histologic types, age of the patient, anatomical location of the carcinoma, and the stage. The RER found in adenoma suggests that RER contributes to the malignant transformation early in the adenoma stage of the gastric carcinogenesis. None of the RER tumors revealed frameshift mutation of the BAX gene.