Intraoperative pelvic brachytherapy for treatment of locally advanced or recurrent colorectal cancer

Background: The aim of this study was to evaluate the efficacy and morbidity of intraoperative radiation therapy (IORT) for advanced colorectal cancer. Methods: All patients undergoing IORT for locally advanced rectal cancer from 2001-2009 were reviewed for cancer recurrence, survival, and procedure-related morbidity. Cumulative event rates were estimated using the method of Kaplan and Meier. Results: Twenty-nine patients with locally advanced (n = 8) or recurrent (n = 21) rectal cancers were treated with IORT and resection. Surgical interventions included low anterior resection, abdominoperineal resection, pelvic exenteration, and a variety of non-anatomic resections of pelvic recurrences. R₀resections were achieved in 16 patients, while R1 resections were achieved in 10, and margins were grossly positive in 3 patients. IORT was delivered to all patients over a median area of 48 (42-72) cm² at a median dose of 12 (12-15) Gy. Local and overall recurrence rates were 24 % (locally advanced group) and 45 % (recurrent group). Median disease-free and overall survival were 25 and 40 months respectively at a median follow-up of 26 (18-42) months. The short-term (≤30 days) complication rate was 45 %. Eight patients developed local wound complications, 5 of which required operative intervention. Four patients developed intraabdominal abscesses requiring drainage. Long-term (>30 days) complications were identified in 11 patients (38 %) and included long-term wound complications (n = 3), ureteral obstruction requiring stenting (n = 1), neurogenic bladder (n = 3), enteric fistulae (n = 2), small bowel obstruction (n = 1), and neuropathic pain (n = 1). Conclusions: Intraoperative brachytherapy is a viable IORT option during pelvic surgery for locally advanced or recurrent colorectal cancer but is associated with high postoperative morbidity. Whether intraoperative brachytherapy can improve local recurrence rates for locally advanced or recurrent colorectal cancer will require further prospective investigation.