Concurrent chemoradiation with capecitabine and weekly irinotecan as preoperative treatment for rectal cancer: results from a phase I/II study

The aim of this study was to investigate the efficacy and safety of chemoradiation using capecitabine and irinotecan as neoadjuvant therapy for patients with rectal cancer. Conventional radiation was given at daily fractions of 1.8 Gy on 5 days a week for a total dose of 55.8 (50.4 + 5.4) Gy. Concurrently, irinotecan 40 mg m(-2) once weekly and capecitabine continuously at dose levels of 500, 650, 750 and 825 mg m(-2) twice daily were administered. Surgery was performed 4-6 weeks following completion of chemoradiation. A total of 28 patients (3 UICC II, 25 UICC III) were enrolled and all received treatment. Dose-limiting toxicity was diarrhoea grade IV and hand-foot syndrome at the 825 mg m(-2) dose level. The maximum tolerated dose of capecitabine was 750 mg m(-2). Diarrhoea was the most common toxicity: grade III in nine patients. Two patients died, one due to pneumonia and one due to sudden cardiac death. A complete response and only microfocal residual tumour disease was achieved in four and three patients (27%). In all, 25 of 28 patients undergoing surgery, 24 (96%) had R0 resection. Preoperative chemoradiation based on continuous daily capecitabine and weekly irinotecan appears to tolerated and effective in patients with rectal cancer.