Pre- versus postoperative radiotherapy in rectal carcinoma: an interim report from a randomized multicentre trial.

Since October 1980 a randomized multicentre trial has been in progress among patients with rectal carcinoma, in whom high-dose fractionated pre-operative irradiation (total dose 25.5 Gy in 5-7 days) is being tested against postoperative irradiation to a high dose level using a conventional fractionation scheme (totally 60 Gy in 8 weeks) delivered only to a high-risk group of patients (Dukes' stages B and C). The primary aim of the trial is to investigate whether local recurrence rate differs between the two groups, and a secondary aim is to see whether 5-year survival will differ between the two groups of patients. Up to October 1984, 360 patients have been randomly allocated to these two groups. Locally curative surgery has been performed in 161 patients in the pre-operative irradiation group and in 152 patients in the postoperative irradiation group. Pre-operative irradiation was extremely well tolerated and there were no irradiation-related complications; 95 per cent of these patients received their treatment according to the intended schedule. However, 48 of the 161 patients had a tumour in Dukes' stage A. Pre-operative radiotherapy had no impact on postoperative mortality or the occurrence of anastomosis dehiscence, but significantly more patients with perineal wound sepsis after an abdominoperineal resection were found in the group of patients receiving pre-operative radiotherapy. This prolonged the stay in hospital after surgery. Postoperative radiotherapy was not so well tolerated as pre-operative treatment, and in a substantial number of patients the treatment could not be commenced until a relatively long time after surgery. To date, the local recurrence rate is acceptably low (approximately 10 per cent) in both treatment groups.