Phase I Trial of Neoadjuvant Preoperative Chemotherapy With S-1 and Irinotecan Plus Radiation in Patients With Locally Advanced Rectal Cancer

With our new regimen, the MTD of irinotecan was 90 mg/m2, and the RD of irinotecan for Phase II studies was 80 mg/m2. Although our results are preliminary, this new neoadjuvant chemoradiotherapy was considered safe and active, meriting further investigation in Phase II studies.