[A cooperative study of surgical adjuvant chemotherapy of colorectal cancer (second report): 3-year survival rate. Cooperative Study Group of Surgical Adjuvant Chemotherapy of Colorectal Cancer in Japan].

To evaluate the efficacy of surgical adjuvant chemotherapy for patients with curatively resected colorectal cancer (excluding m and sm cancer), a randomized controlled study was performed from January 1982 to October 1983. The schedules for drug administration were different in four districts, and four randomly assigned protocols were studied using tegafur (FT), ACNU, MMC and ADM. A total of 4,906 cases from 491 institutions were entered and 4,206 cases were varied for the study. There were no significant differences in 3-year survival rate in each district protocol. According to Dukes C for rectal cancer patients, ADM + FT group was higher than the FT only group in 3-year survival rate (p = 0.092) and had a significantly longer survival than FT only group in 3-year disease-free rate (p = 0.011). The rate of local recidivation in colon cancer resected curatively was higher in ACNU + FT group than in FT only group (p less than 0.05). A tendency for decreased liver metastasis was observed in FT group compared with the control group, and liver metastasis of ADM + FT group was lower than that of FT only group. No serious adverse effects were observed in any protocol.