Intraoperative Radiation Therapy for Locally Advanced or Locally Recurrent Rectal Cancer

Colorectal cancer is a major cause of morbidity and mortality across the world. Although surgery alone is very effective for patients with early stage disease, patients with more advanced disease required a combined modality approach. Standard doses of radiation therapy are usually ineffective in controlling localized disease that cannot be widely resected. Radiation dose escalation with intraoperative radiation therapy (IORT) has been investigated for many years as a component of a trimodality strategy in patients at high risk for local recurrence. This paper reviews the evidence supporting inclusion of IORT in addition to external beam radiation, surgery, and chemotherapy in patients with very locally advanced primary rectal cancer and patients with locally advanced recurrent rectal cancer.