The Role of Re-irradiation for Locally Recurrent Rectal Cancer

Treatment of colorectal cancer has improved significantly due to advances in chemo-and/ or radiotherapy and better surgical management. Local recurrence in the modern era of rectal surgery occurs in approximately 4-11% of patients. The role of chemoradiation therapy to further reduce recurrence rates in primary treatment of rectal cancer patients is well established. This chapter outlines the evidence regarding re-irradiation of locally recurrent rectal cancer. Re-irradiation is therefore challenging because the surrounding tissues have already received doses near the organ-specific tolerance dose during the primary treatment. Toxicity as a result of re-irradiation has been reported in several studies in the literature. Overall, toxicity following re-irradiation is well tolerated but is increased in those undergoing surgery. Generally, toxicity is modest, with grade 3 or higher acute toxicity reported in 2-4%, nausea/vomiting in 4%, skin damage in 5-8%, and acute diarrhea in 10-20% of patients.