PHASE-II STUDY OF PULSE 5-FLUORO-2'-DEOXYURIDINE AND LEUCOVORIN IN ADVANCED COLORECTAL-CANCER PATIENTS PREVIOUSLY TREATED WITH CHEMOTHERAPY

Because of possibly better activity against colorectal cancer of 5-flu oro-2'-deoxyuridine [floxuridine (FUdR)] compared to 5-fluorouracil (5 -FU), and because of improved therapeutic results of leucovorin (LV) m odulation of 5-FU, we carried out a phase II study of systemic FUdR an d LV in 5-FU-treated patients with metastatic colorectal cancer. Weekl y regimens consisted of a 4-hour infusion of LV, 200 mg/m2, and at 2 h ours, a 2-hour infusion of FUdR, 30 mg/kg, with weekly dose escalation , as tolerated, to a maximum of 60 mg/kg. Twenty-nine patients were tr eated; they had a median age of 66, most had good performance status, and all had measurable disease. All had received 5-FU, although three had received it as adjuvant therapy only. Two patients had partial res ponses (6.9% response rate, 95% confidence interval, 1.9-21.9%) lastin g 29 and 19 weeks, and five had stable disease. Median time to progres sion was 8 weeks and median survival was 36.5 weeks. The median number of courses was 6.5; escalation of FUdR was carried out in 27 patients . Hematologic toxicity was minimal and gastrointestinal toxicity was m ost frequent, although mild. This regimen, although well tolerated, is minimally effective in previously 5-FU-treated patients with metastat ic colorectal cancer.