A phase I study of oral UFT/leucovorin and irinotecan, plus radiation for locally recurrent rectal cancer

Objectives: The aim of this phase I study is to identify the maximum tolerated dose (MTD) and recommended dose (RD) of CPT-11 in combination with UFT/LV and radiation in patients with locally recurrent rectal cancer. Methods: Patients with histologically proven rectal cancer with local recurrence were eligible for this study. Escalating doses of CPT-11 (30-60 mg/m2) were administered on days 3, 10, 24, and 31. UFT (300 mg/m2) and LV (75 mg/body) were given on days 1-5, 8-12, 22-26, and 29-33. Radiotherapy doses consisted of 50 Gy in daily fractions of 2.0 Gy each, 5 times per week, for total 5 weeks. Results: We recruited 27 patients, and the MTD of CPT-11 was 60 mg/m2 due to the occurrence of dose-limiting toxicity of grade 3 diarrhea. Major grade 3 adverse events were neutropenia (5/27; 18.5%) and diarrhea (6/27; 22.2%). No grade 4 adverse event was observed throughout this treatment. Conclusions: The combined chemoradiotherapy with oral UFT/LV plus CPT-11 is feasible and promising. The recommended dose for further phase II trials is determined to be 50 mg/m2 of CPT-11.