Stereotactic body radiotherapy for isolated paraaortic lymph node recurrence from colorectal cancer

AIM: To evaluate the efficacy and complications of stereotactic body radiotherapy in localized paraaortic lymph node recurrence from colorectal cancer. METHODS: From 2003 to 2009, 7 patients with paraaortic lymph node recurrence (1-3 lesions) from colorectal cancer were treated with stereotactic body radiotherapy. Total gross tumor volumes ranged from 4 to 40 mL. The doses were escalated from 36 Gy/patient to 51 Gy/patient and were delivered in 3 fractions. RESULTS: One and 3 year overall survival rates were 100% and 71.4%, respectively, and median survival was 37 mo. Grade Ⅳ intestinal obstruction was reported in 1 of 7 patients. This patient received 48 Gy in 3 fractions with a maximum point dose to the intestine of 53 Gy and V_(45Gy) = 3.6 mL. However, 6 patients received an intestinal maximum point dose of < 51 Gy and V_(45Gy) of < 1 mL, and did not develop any severe complications. CONCLUSION: This pilot study suggests selected paraaortic lymph node recurrence (1-3 closed lesions) that failed to respond to chemotherapy can be potentially salvaged by stereotactic body radiotherapy.