Surgery and high-dose-rate intraoperative radiation therapy for recurrent squamous-cell carcinoma of the anal canal

BACKGROUND: Locoregionally recurrent squamous-cell carcinoma of the anal canal is managed with salvage surgery. High-dose-rate intraoperative radiation therapy has been used in selected patients with this disease to reduce the risk of local recurrence. OBJECTIVE: The aim of this article is to present our institutional experience with this technique. DESIGN: Medical records of 14 patients with locoregionally recurrent squamous-cell carcinoma of the anal canal who underwent this technique between 1992 and 2007 were reviewed. SETTING: The study was conducted at an academic cancer center. PATIENTS: The median age was 45 years (range, 36-77), and 13 of the patients were women. All had prior radiation with or without chemotherapy. INTERVENTIONS: The surgical procedures included abdominoperineal resection with or without sacrectomy (n = 8), low anterior resection (n = 2), and pelvic exenteration (n = 4). The median radiation dose was 1500 cGy (range, 1500-1750). All cases of radiographic invasion of adjacent structures correctly predicted pathologic invasion. There was pathologic invasion into adjacent structures in 11 cases (79%), and adherence to the sacrum without invasion in 2 cases (14%). Surgical margins were positive (n = 6), close (< 1 mm) (n = 3), and negative (n = 5). RESULTS: The median follow-up from our technique was 17 months (range, 5-145). Subsequent recurrence occurred in 11 cases, at a median of 8 months from treatment. Two-year actuarial control was 7.1%, and the overall survival was 21.4%. Acute toxicities included wound-healing complications (n = 6); gastrointestinal obstruction (n = 5); neurogenic bladder (n = 1); ureteral stricture (n = 3); and peripheral neuropathy (n = 2). LIMITATIONS: This is a small retrospective series in which the meaningful analysis of associations between clinical variables and outcomes was not possible. CONCLUSION: Salvage surgery with high-dose-rate intraoperative radiation therapy did not appear to be associated with a locoregional control or survival benefit in this series. The addition of high-dose-rate intraoperative radiation therapy to salvage surgery is insufficient to compensate for positive surgical margins. Preoperative imaging should be used to aid in patient selection to identify those patients in whom negative margins can be obtained and to aid in the determination of appropriate salvage surgery.