Prospective controlled study on the usefulness of Carmofur as a postoperative adjuvant chemotherapy for colorectal cancer

A prospective controlled study, the 7th cooperative study of the Japanese Foundation for Multidisciplinary Treatment, was conducted to evaluate the usefulness of concomitant therapy with MMC + HCFU as a postoperative adjuvant therapy in patients with colorectal cancer who had undergone curative resection for a period of 2 years and 11 months from February, 1986. The Dukes B and C patients with colorectal cancer classified by macroscopic examination who had an intravenous MMC 6 mg/m2 on the day of operation and followed by oral HCFU for 12 months from 2 weeks after operation (Group X) were compared with patients who had operation only (Group Y). Some 978 patients with colon cancer and 713 patients with rectal cancer were enrolled in the study, 85 (5.0%) of whom were not eligible. The 5-year survival rate of Group X in colon cancer was 79.3% and that of Group Y was 76.4%: thus the survival rate of Group X was slightly better than that of Group Y, but no significant difference was found between the two groups. Subset analysis revealed that the survival rate of Group X in advanced cancer of stage III b + IV, according to the General Rules for Clinical and Pathological Studies on Cancer of the Colon, Rectum and Anus in Japan, was 62.4% and that of Group Y was 46.2%. Thus, the survival rate of Group X was significantly better than that of Group Y (logrank test: p = 0.035, generalized Wilcoxon test: p = 0.025). The disease-free survival rate was not significantly different between the groups with colon cancer and rectal cancer. The above results suggest that HCFU is useful for patients with a high risk of recurrence who had advanced colon cancer (stage III b + IV). However, additional prospective studies are required to verify them.