Phase I/II study of irinotecan and UFT for advanced or metastatic colorectal cancer.

UNLABELLED: The aim of this study was to determine the recommended dose of irinotecan in combination with the fixed dose of oral UFT as first-line therapy in patients with advanced or recurrent colorectal cancer, and to evaluate the response rate and overall survival as a phase II study. PATIENTS AND METHODS: Thirteen patients were recruited into a phase I trial. Four doses of irinotecan ranging from 60 to 150 mg/m2/day were administered intravenously on day 1 and day 16 in combination with UFT given orally from day 2 to day 15. In a phase II study, 53 patients received at least one cycle of this therapy. RESULTS: The recommended dose of this combination was determined as irinotecan 120 mg/m2/day and UFT 400 mg/m2/day. Dose-limiting toxicities were neutropenia and prolonged leucopenia. On an intent-to-treat analysis, the response rate in the phase II study was 24.5% (95% confidence interval 13.8% to 38.2%). The median overall survival time was 20.3 months (95% confidence interval, 15.0-22.8 months). Out of 20 patients with stable disease, 17 who received more than 4 cycles of the regimen lived longer than the other 3 patients who received fewer than 3 cycles (p = 0.0353). Hematological adverse events were mainly grade 3/4 neutropenia observed in 6 out of 53 patients. Grade 3 non-hematological toxicities, such as diarrhea, anorexia, nausea/vomiting and alopecia were observed in 6 patients. CONCLUSION: Irinotecan combined with oral UFT was effective and well-tolerated. This regimen may be considered as a first-line therapy for advanced or metastatic colorectal cancer and may result in fairly long survival, even for patients with stable disease.