Related Experiment Video
Updated: Mar 18, 2026
Proton Therapy Delivery and Its Clinical Application in Select Solid Tumor Malignancies
Published on: February 6, 2019
Carbon-Ion Radiation Therapy for Pelvic Recurrence of Rectal Cancer
Shigeru Yamada1, Tadashi Kamada1, Daniel K Ebner2
1Research Center Hospital for Charged Particle Therapy, National Institute of Radiological Sciences, Chiba, Japan.
Purpose:
Investigation of the treatment potential of carbon-ion radiation therapy in pelvic recurrence of rectal cancer.
Methods And Materials:
A phase 1/2 dose escalation study was performed. One hundred eighty patients (186 lesions) with locally recurrent rectal cancer were treated with carbon-ion radiation therapy (CIRT) (phase 1/2: 37 and 143 patients, respectively). The relapse locations were 71 in the presacral region, 82 in the pelvic sidewalls, 28 in the perineum, and 5 near the colorectal anastomosis. A 16-fraction in 4 weeks dose regimen was used, with total dose ranging from 67.2 to 73.6 Gy(RBE); RBE-weighted absorbed dose: 4.2 to 4.6 Gy(RBE)/fraction.
Results:
During phase 1, the highest total dose, 73.6 Gy(RBE), resulted in no grade >3 acute reactions in the 13 patients treated at that dose. Dose escalation was halted at this level, and this dose was used for phase 2, with no other grade >3 acute reactions observed. At 5 years, the local control and survival rates at 73.6 Gy(RBE) were 88% (95% confidence interval [CI], 80%-93%) and 59% (95% CI, 50%-68%), respectively.
Conclusion:
Carbon-ion radiation therapy may be a safe and effective treatment option for locally recurrent rectal cancer and may serve as an alternative to surgery.
