Radiotherapy combined with curative surgery. Its use as therapy for carcinoma of the sigmoid colon and rectum.

Local recurrence rates for colorectal carcinoma occur in the range from 20% to 35%. For this reason, postoperative radiotherapy was evaluated as a measure to achieve local disease control in the pelvis. Patients with tumors penetrating the entire bowel wall or with regionally involved lymph nodes received approximately 5,000 rads over a six-week period that commenced three to six weeks after surgery. Sixty-two patients treated by this method are compared with 168 patients treated without adjunctive radiotherapy. Five local recurrences occurred in the group receiving radiotherapy; a reduced incidence compared to the group managed by surgery alone. Complications attributable to radiotherapy included radiation enteritis and bowel obstruction. Measures to minimize complications with this combined approach have been identified. Surgery followed by adjuvant radiotherapy may be performed with an acceptable complication rate and this appears promising in reducing local recurrence of carcinomas of the sigmoid colon and rectum.