Is gastric carcinoma different between Japan and the United States? A comparison of patient survival among three institutions

BACKGROUND. Analyses of surgical results fur gastric carcinoma often lead t o the conclusion that gastric carcinoma occurring in Japan is different hor n that diagnosed in the U.S. METHODS. To elucidate factors that might explain the differences in surgica l results between the two countries, the authors compared data from a cance r center and a university hospital in Japan and a specialist cancer hospita l in the U.S (Memorial Sloan-Kettering Cancer Center [MSKCC]). RESULTS. The mean age and body mass index were significantly greater in pat ients in the U.S. The N category appeared to be determined less accurately at MSKCC compared with the Japanese centers. The occurrence of early gastri c carcinoma was not confined to Japanese patients because 20% of U.S. patie nts who underwent surgery were determined to have early stage disease. Howe ver, mucosal (in situ) carcinoma was detected rarely, and the proportion of advanced stage disease was greater in the U.S. Lesions in the upper gastri c body, including the gastroesophageal junction, occurred in > 50% of cases at MSKCC but in only 20% of cases at the Japanese centers (P < 0.001). D2 lymph node dissection was possible with low morbidity and minimum mortality (31% and 3%, respectively, at MSKCC). The 5-year survival rates, stratifie d by tumor location and T category, revealed more similar results between J apan and the U.S. than had been reported previously. The marked difference between Japanese and American institutions only was observed for T1 and T2 tumors occurring in the lower gastric body and for T3 tumors occurring in t he middle and upper third of the stomach. CONCLUSIONS. Based on the findings of the current study, it would appear th at the more favorable outcome noted for gastric carcinoma patients in Japan primarily is explained by the differences in tumor location, a greater fre quency of early stage disease, and more accurate staging compared with gast ric carcinoma patients in the U.S. Results of gastric carcinoma treatment c omparable to those obtained in Japan can he obtained in Western centers. Ca ncer 2000;89:2237-46. (C) 2000 American Cancer Society.