MIAMI BEACH--Sphincter-preserving surgical techniques can be safely and effectively combined with high-dose preoperative radiation for tumors in the most distal segments of the rectum, Mohammed Mohiuddin, MD, said at the American Society for Therapeutic Radiology and Oncology (ASTRO) meeting.
Dr. Mohiuddin, professor and chairman, Department of Radiation Medicine, University of Kentucky, Lexington, reported that this approach resulted in excellent local control, improved survival, and enhanced quality of life, with retention of normal anal sphincter function in the majority of patients.
His conclusions are based on results in 70 patients with tumors in the distal 2 cm of the rectum who were part of a series of 259 rectal cancer patients enrolled in a program of high-dose preop-erative radiation and sphincter-preserving surgery. All surgeries were performed by Gerald Marks, MD, who is now professor of surgery, Medical College of Pennsylvania-Hahnemann University.
"The availability of anastomic stapling devices and the introduction of new surgical techniques have expanded the options for sphincter-preservation surgery to more distal segments of the rectum, providing an alternative to abdominal perineal resection and loss of anal function," Dr. Mohiuddin said.
However, he added, current approaches for surgical resection of rectal cancer still call for a 2 cm distal margin to prevent excessive local disease recurrence. "Sphincter-preservation surgery has thus been limited to tumors at least 2 cm proximal to the anal-rectal junction," he said.
In the current series, all patients received a minimum dose of 40 to 45 Gy over 4½ weeks at 1.8 to 2.5 Gy per fraction. Patients with unfavorable tumors were given an additional boost of 10 to 15 Gy. Surgery was performed 4 to 10 weeks after the completion of radiation therapy. Median follow-up was 4 years.
Overall, there was one perioperative mortality. Two patients did not have their colostomy closed because of complications. Four patients required late colostomies because of local recurrence. Sixty patients (86%) maintained satisfactory long-term sphincter function.