The Stockholm II trial on preoperative radiotherapy in rectal carcinoma: long-term follow-up of a population-based study

Abstract

BACKGROUND The Stockholm II trial is a population-based prospective randomized trial on preoperative radiotherapy in rectal carcinoma. METHODS Eligibility criteria were age younger than 80 years and biopsy-proven adenocarcinoma of the rectum judged resectable for cure with an abdominal procedure. Between 1987 and 1993, 557 patients were included. Patients were randomized to preoperative radiotherapy (RT+) followed by surgery within a week (n = 272) or surgery alone (RT−; n = 285). Radiotherapy was given with 25 grays in 1 week to the rectum and pararectal tissues. Curative resection was performed in 481 patients (86%). Median follow-up was 8.8 years. RESULTS Among patients who underwent curative surgery, the incidence of pelvic recurrence was 12% (RT+) and 25% (RT−), respectively (P < 0.001). The overall survival rate in irradiated patients who underwent curative surgery was improved (46%) versus (39%; P < 0.03). For all included patients, the difference was 39% (RT+) compared with 36% (RT−; P = 0.2). Within 6 months of surgery, 13 of 272 (5%) of the irradiated patients died of intercurrent disease versus 4 of 285 (1%) of the nonirradiated (P = 0.02). Cardiovascular death was the main cause of intercurrent death and occurred in 35 of 272 (13%) of the irradiated patients compared with 20 of 285 (7%) among the nonirradiated (P = 0.07). CONCLUSIONS Preoperative short-term radiotherapy reduces the risk of pelvic recurrence and can improve survival after curative surgery for rectal carcinoma. An increased risk of intercurrent death may reduce the benefit especially in elderly patients. Cancer 2001;92:896–902. © 2001 American Cancer Society.