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 twenty-nine patients with 134 sites of locally recurrent cancer receiving carbon ion radiotherapy were analyzed.Fifty-eight relapses originated in the presacral region, 45 in the pelvic sidewalls, 20 in the perineal region and 9 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 the 104 lesions 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 98% at one year and 95% at 5 years. The dose escalation was then halted at this level. The median survival in the patients treated with 73.6 GyE was 54 months (range, 7 to 82 months), and the overall survival rates were 74% at 3 years and 45% 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 unacceptableThe 4th Japanese-European Joint Symposium on Ion Cancer Therap