Purpose: Patients with cT2N0 distal rectal cancer do not require adjuvant therapy. However, when a patient refuses an abdominoperineal resection (APR), is there an alternative? The purpose of this trial is to determine whether preoperative external-beam radiation therapy can increase the rate of sphincter preservation for patients with distal cT2N0 adenocarcinoma of the rectum.
Patients and methods: Between April 1988 and October 2003, 27 patients with distal rectal adenocarcinoma staged T2 by clinical and/or endorectal ultrasound who were judged by the operating surgeon to require an APR were treated with preoperative pelvic radiation alone (50.4 Gy). Surgery was performed 4 to 7 weeks later. If pathologic positive pelvic nodes were identified, postoperative adjuvant chemotherapy was recommended. The median follow-up was 55 months (range, 9 to 140 months).
Results: The pathologic complete response rate was 15% and 78% of patients underwent a sphincter-sparing procedure. The crude incidence of local failure for patients undergoing a sphincter sparing procedure was 10% and the 5-year actuarial incidence was 13%. The actuarial 5-year survival for patients undergoing sphincter preservation was as follows: disease-free, 77%; colostomy-free, 100%; and overall, 85%. Using the Memorial Sloan-Kettering Cancer Center sphincter function score, 54% of those undergoing a sphincter-sparing procedure had good/excellent bowel function at 12 to 24 months after surgery, and 77% had good/excellent function at 24 to 36 months after surgery.
Conclusion: Our data suggest that for patients with cT2N0 distal rectal cancer who require an APR, preoperative pelvic radiation improves sphincter preservation without an apparent compromise in local control or survival.