[Mitomycin C plus HCFU adjuvant chemotherapy for noncuratively resected cases of colorectal carcinoma. (Second report): 5-year survival rate. Cooperative Study Group of Kyushu and Chugoku for HCFU Adjuvant Chemotherapy].

In order to examine the efficacy of adjuvant chemotherapy employing mitomycin C (MMC) and carmofur (HCFU) for patients with noncuratively resected colorectal carcinoma, a cooperative study was performed by 54 institutions in the Kyushu and Chugoku areas of Japan. The criteria for patient selection were as follows: 1) Age of 75 years or less and not accompanied by any serious disease. 2) Macroscopic diagnosis as being noncuratively resected on completion of the surgical procedure. 3) Definitive diagnosis of colorectal carcinomas, histologically. 4) No synchronous or metachronous double cancer. The prospective randomized controlled study consisted of two groups. In Group A, the MMC group received bolus intravenous injections of 20 mg MMC on the day of operation and 10 mg the next day, followed by 10 mg every 4 weeks until a total of 100 mg had been administered. In Group B, the MMC + HCFU group received the same treatment in Group A, but with the addition of 600 mg/day of HCFU from the second week, orally for at least one year. Concerning the 69-month survival rate, a better result was observed in the MMC + HCFU group than in the MMC only group (generalized Wilcoxon test: p less than 0.05). Significantly better survival rates were obtained in those cases with disseminating peritoneal metastasis, hepatic metastasis and stage V cancer in the MMC + HCFU group as when compared with the MMC only group. No significant side effects due to the combined administration of HCFU were recognized. The combined administration of MMC and HCFU was suggested to be a safe and effective adjuvant chemotherapy for noncuratively resected cases of colorectal carcinoma.