Chemotherapy with Preoperative Radiotherapy in Rectal Cancer

Background Preoperative radiotherapy is recommended for selected patients with rectal cancer. We evaluated the addition of chemotherapy to preoperative radiotherapy and the use of postoperative chemotherapy in the treatment of rectal cancer. Methods We randomly assigned patients with clinical stage T3 or T4 resectable rectal cancer to receive preoperative radiotherapy, preoperative chemoradiotherapy, preoperative radiotherapy and postoperative chemotherapy, or preoperative chemoradiotherapy and postoperative chemotherapy. Radiotherapy consisted of 45 Gy delivered over a period of 5 weeks. One course of chemotherapy consisted of 350 mg of fluorouracil per square meter of body-surface area per day and 20 mg of leucovorin per square meter per day, both given for 5 days. Two courses were combined with preoperative radiotherapy in the group receiving preoperative chemoradiotherapy and the group receiving preoperative chemoradiotherapy and postoperative chemotherapy; four courses were planned postoperatively in...