Surgical resection and high dose rate intraoperative radiation therapy for locally recurrent rectal cancer.

For intra-pelvic recurrence of rectal cancer, surgical resection is technically difficult and must be aggressive to achieve a high rate of negative resection margins. Resection with clear margins can be curative, particularly for those patients with true anastomotic recurrence. HDR-IORT is a safe, feasible, versatile, logistically sound modality that is highly reliable in delivering radiation to at-risk surgical margins in the pelvis. Despite surgery and IORT, overall local failure rates in this population are 33 to 50 percent. The most important prognostic variable is the state of surgical resection margins. At our institution, in patients with negative and positive resection margins the 2-year actuarial local recurrence rates are 33 percent versus 73 percent and 5-year survival rates are 51 percent versus 16 percent, respectively. On subset analysis, the most favorable outcome was seen in patients with true anastomotic recurrences (78 percent 5-year survival).