Postoperative radiotherapy in rectosigmoid cancer Dukes' B and C: interim report from a randomized multicentre study

The design, and complications seen during the first 2 years, of a randomized trial of postoperative radiotherapy for rectosigmoid cancer Dukes' B and C are presented and discussed. It is concluded that the present complication rate-below 10% in 221 patients-permits continuation of the intake, which is planned to include 550 patients, to demonstrate a possible increase in crude 5-year survival by 15% (60-75% in Dukes' B and 25-40% in Dukes' C), on the basis of a 0·01 significance level and a probability that the experiment will be successful of 0·90.