[Cooperative study of surgical adjuvant chemotherapy for colorectal cancer. Cooperative Study Group of Surgical Adjuvant Chemotherapy for Colorectal Cancer in Japan]

Abstract

With the cooperation of 357 institutions nationwide, during the two years from January 1984 to December 1985, curative resection cases of colorectal cancer were divided into two groups and treated in the following method: A group with chemotherapy received MMC 12 mg/m2, on the day of operation, followed by 6 mg/m2 every two months, 6 times. From the second week after operation, 800 mg/body/day of FT was administered for one year. The other was a control group with operation only. In this study, targetting those cases in which recurrence was observed within 5 years, among eligible cases histologically curative resection, recurrence forms were examined by prognostic factors and usefulness of adjuvant chemotherapy after operation. Regarding the recurrence of liver metastasis, in the case of colon cancer, the effect of chemotherapy was observed in highly positive cases of lymph node metastasis and positive cases of lymphatic vessel invasion. In rectal cancer, it was noticed in Dukes C cases. For the local recurrence of rectal cancer, it was observed in Dukes C and cases of relative curative resection. Chemotherapy tended to inhibit recurrence within one year after the operation in both liver metastasis and local recurrence.