Irradiation of Very Locally Advanced and Recurrent Rectal Cancer.

Adjuvant therapy with chemoradiation or short-course radiation in addition to improvements in surgical technique has led to improved outcomes for patients with locally advanced rectal cancer. Local recurrence rates of less than 10% and 5-year survival rate of 60% or higher is expected. However, for patients with very locally advanced primary or locally recurrent disease in whom surgical resection is likely to be associated with incomplete resection, survival and disease control rates are poor and standard doses of adjuvant radiation or chemoradiation are relatively ineffective. Dose-escalation approaches with intraoperative radiation (IORT) have been explored in both the primary and recurrent setting. Although high-level evidence is lacking, available data suggest improvements in local and distant control leading to improved survival with IORT approaches. This review summarizes the evidence for dose-escalation approaches with IORT for patients with very locally advanced and recurrent rectal cancer.