Combination chemotherapy for advanced colorectal cancer. A pilot study.

Twenty-three patients with advanced colorectal carcinoma, mostly with liver and lung metastases and measurable disease, were treated with mitomycin-C 20 mg/m2 I.V. and vincristine 1.2 mg/m2 I.V. every 6 weeks, and cisplatinum 50 mg/m2 I.V. and 5-fluorouracil 1,000 mg/m2/24 hours I.V. continuous infusion for 96 hours every 3 weeks based upon the hypothesis that cisplatinum may potentiate the antitumor activity of antimetabolites and alkylating agents. Five patients had received prior chemotherapy and six had received prior radiotherapy, with one of these patients receiving both. One complete and 10 partial responses were observed, with an overall response rate of 48% (90% confidence interval 30-70%). The toxicity was manageable. A possible potentiating effect of cisplatinum is suggested in this first attempt in the treatment of colorectal cancer, and warrants further exploration.