Fifty-three patients with advanced metastatic colorectal carcinoma were treated every 4-5 weeks with a chemotherapeutic regimen consisting of 5-FU (300 mg/m2 iv on Days 1-5), mitomycin (10 mg/m2 iv on Day 1 only [repeated every other course]), vincristine (0.75 mg/m2 on Days 1 and 5), and methotrexate (8.0 mg/m2 iv on Days 1 and 5). The overall response rate was 43.4%, with three patients (5.7%) achieving complete response (mean duration, 13.3 months) and 20 patients (37.7%) achieving partial response (mean duration, 6.3 months). Stable disease was not considered to be a response category in this report. The mean overall response duration was 7.8 months. The observed mean survival duration in responders was 15.2 months and in nonresponders was 8.9 months (P less than or equal to 0.01). Hematologic and subjective toxic effects are discussed.