A Phase II Trial of Neoadjuvant Preoperative Chemoradiotherapy With S-1 Plus Irinotecan and Radiation in Patients With Locally Advanced Rectal Cancer: Clinical Feasibility and Response Rate

A preoperative regimen of S-1, irinotecan, and radiotherapy to the rectum was feasible, and it appeared safe and effective in this nonrandomized Phase II setting. It exhibited a low incidence of adverse events, a high rate of completion of treatment, and an extremely high rate of pathologic complete response.