[5-Fluorouracil plus low-dose leucovorin in the treatment of advanced colorectal cancer].

From September 1989 to September 1992, 17 patients (pts) with non-curative or recurrent colorectal cancer were treated with 5-fluorouracil (FU) plus leucovorin (LV) systemic therapy. The sites of evaluable metastases were liver (10), peritoneum (4), lung (3) and others (6). The LV dosage was 30 mg/body (low-dose method) and the FU dosage was 500-750 mg/body. Both drugs were administered either 5 days/every 4 weeks or one day/every 1 to 2 weeks via protracted or bolus infusion. The regimen was generally well tolerated, although 9 pts (53%) experienced toxicity which required dose reductions. Overall response rate was 29% (5 PR). No CR was observed. Improvement in tumor-related symptoms was noted temporarily in 7 out of 10 pts. Serum CEA level decreased in 13 out of 14 pts. All the response sites were liver (5), with simultaneous lung (1) or peritoneum (1) metastasis. The response duration was 3 to 10 months (mean 6.2 months). Second-line therapy after progression of diseases, such as combination with CDDP, was attempted in some of the PR pts, but no re-response was observed. We conclude that FU plus low-dose LV regimen is an effective therapy for advanced colorectal cancer, but further attempts should be made to increase response rate, prolongation of response duration and effective second-line therapy after progression.