Impact of carbon ion radiotherapy for unresectable osteosarcoma of the trunk

Abstract

Background: The authors summarized the outcomes of patients with unresectable osteosarcoma of the trunk who received carbon ion radiotherapy (CIRT).

Methods: The authors performed a retrospective analysis of 78 patients who had medically inoperable osteosarcoma of the trunk and received treatment with CIRT between 1996 and 2009. Tumor sites included the pelvis in 61 patients, the spine and paraspinal region in 15 patients, and other sites in 2 patients. The median applied CIRT dose was 70.4 Gray equivalent (GyE) in a total of 16 fixed fractions over 4 weeks.

Results: The minimum duration of follow-up for survivors was 14 months. Forty-eight patients remained alive. The 5-year overall survival rate was 33%, and the local control rate was 62%. Thirty-eight patients who had a clinical target volume <500 cm(3) had a 5-year overall survival rate of 46% and a 5-year local control rate of 88%. Except for 3 patients who experienced severe skin/soft tissue complications requiring skin grafts, no other severe toxicities were observed. Of 9 patients who were continuously disease free for >5 years, 8 were able to walk with or without the help of a cane, and 6 were free from pain killers.

Conclusions: CIRT appeared to be a safe and effective modality for the management of unresectable osteosarcoma of the trunk, providing good local control and offering a survival advantage and good long-term functional results without unacceptable morbidity.