Carbon ion Therapy for Patients with Locally Recurrent Rectal Cancer

Purpose: To evaluate the tolerance for and effectiveness of carbon ion radiotherapy in patients with locally recurrent rectal cancer.Patients and Methods: We conducted a phase I/II dose escalation study of carbon ion radiotherapy. One hundred patients with 105 sites of locally recurrent cancer receiving carbon ion radiotherapy were analyzed. Forty-eight relapses originated in the presacral region, 28 in the pelvic sidewalls, 16 in the perineal region and 8 in the colorectal anastomosis. The total dose ranged from 67.2 to 73.6 gray equivalent (GyE) and was administered in 16 fixed fractions over 4 weeks (4.2 to 4.6 GyE/fraction). Results: None of 75 patients treated with the highest total dose of 73.6 GyE experienced National Cancer Institute - Common Toxicity Criteria grade 3 to 5 acute reactions. The local control rate in patients treated with 73.6 GyE in the present study was 97% at one year and 92% at 3 years. Dose escalation was then halted at this level. The median survival time in patients treated with 73.6 GyE was 54 months (range, 7 to 65 months), and the 1- and 3-year overall survival rates were 71% at 3 years and 39% at 5 years, respectively.Conclusion: Carbon ion radiotherapy seems to be a safe and effective modality in the management of locally recurrent rectal cancer, providing good local control and offering a survival advantage without unacceptable morbidity.NIRS-ETOILE Joint Symposium 2009 on Carbon Ion Radiotherap