Cooperative study of surgical adjuvant chemotherapy of colorectal carcinoma (second study): a preliminary report. Cooperative Study Group of Surgical Adjuvant Chemotherapy of Colorectal Cancer in Japan]

In a prospectively randomized study, the effect of adjuvant chemotherapy with mitomycin C (MMC) and tegafur (FT) on survival and recurrence was analyzed in 2,477 evaluable patients with colon or rectal cancer who underwent macroscopically curative resection. Patients (1,256 with colon cancer, 1,221 with rectal cancer) were divided into the treatment group (group A) and the control group (surgical resection only, group B). In group A, chemotherapy consisted of intravenous administration of MMC (12 mg/m2 on operative day, followed by 6 mg/m2/2 months, 6 times) and oral administration of FT (800 mg/day for one year). No serious adverse effects were observed in the treatment group. There was no significant difference between group A and group B in three-year survival rate. The disease-free interval curve in group A of rectal cancer revealed significantly better results than group B (p = 0.044). There was no difference in the incidence of local recurrence at three years after operation between group A and group B. The incidence of metachronous liver metastases in group A of rectal cancer was significantly lower than in group B (p = 0.036).