Effect of preoperative irradiation on resectability of colorectal carcinomas.

From 1968 to January 1, 1977, 44 patients with initially unresectable colorectal carcinoma were treated with preoperative radiotherapy and surgery. On presentation, unresectability was determined either clinically (26 patients) or by preradiotherapy laparotomy (18 patients). Preoperative irradiation consisted of 4500-5000 rad. After radiotherapy, 33 of 44 lesions were considered resectable. Seven of 33 patients underwent incomplete resection with mean survival of 17 months. Resection was complete in 26 of the 33 patients. Of the latter group (26), 18 patients are alive with no evidence of disease with minimum follow-up of 36 months. Detailed results are discussed.