5-Fluorouracil and low-dose leucovorin in metastatic colorectal cancer: a pilot study.

A total of 56 consecutive patients with metastatic colorectal cancer received treatment with 5-fluorouracil (5-FU) given at 425 mg/m2 by rapid intravenous infusion, immediately preceded by leucovorin (LV) given at 20 mg/m2, with cycles being repeated every 4 weeks. Of 48 evaluable patients undergoing this treatment, a tumor response was observed in 16 (33%); a complete response, in 2 (4%); and a partial response, in 14 (29%). The median survival was 8.5 months for all patients and 16.5 months for responders. An improvement in symptoms was seen in 9 (26%) of 34 symptomatic patients. In all 15 (27%) of 44 evaluable patients showed an improvement in performance status. The most significant toxicity attributable to the treatment was mucositis of grade 3 or 4, seen in 27% of the patients. Altogether, 2 patients (3.5%) were hospitalized for treatment-related toxicity. We conclude that the combination of 5-FU and low-dose LV is active in advanced colorectal cancer and is associated with acceptable toxicity.