Background: Adjuvant radiotherapy for rectal cancer has been extensively studied, but no trial has unequivocally demonstrated improved overall survival with radiotherapy, despite a reduction in the rate of local recurrence.
Methods: Between March 1987 and February 1990, we randomly assigned 1168 patients younger than 80 years of age who had resectable rectal cancer to undergo preoperative irradiation (25 Gy delivered in five fractions in one week) followed by surgery within one week or to have surgery alone.
Results: The irradiation did not increase postoperative mortality. After five years of follow-up, the rate of local recurrence was 11 percent (63 of 553 patients) in the group that received radiotherapy before surgery and 27 percent (150 of 557) in the group treated with surgery alone (P<0.001). This difference was found in all subgroups defined according to Dukes' stage. The overall five-year survival rate was 58 percent in the radiotherapy-plus-surgery group and 48 percent in the surgery-alone group (P=0.004). The cancer-specific survival rates at nine years among patients treated with curative resection were 74 percent and 65 percent, respectively (P=0.002).
Conclusions: A short-term regimen of high-dose preoperative radiotherapy reduces rates of local recurrence and improves survival among patients with resectable rectal cancer.