Outcomes and toxicity of radiotherapy for refractory bone and soft tissue sarcomas

Surgical resection is a well-established treatment option for sarcoma. However, anatomical barriers often hamper radical surgical procedures. The treatment of unresectable sarcoma, including local or distant failures following initial treatment, is challenging. The aim of the present study was to analyze the outcome of radiotherapy (RT) for refractory sarcoma, including unresectable, metastatic and recurrent disease, following radical treatment. We retrospectively reviewed a total of 67 tumors in 28 patients who were treated with RT between 2007 and 2014. Clinical target volume (CTV) was generally not defined in a preventive manner; therefore, in the majority of the cases, CTV equaled the gross tumor volume. The total delivered dose, number of fractions and biological equivalent dose were 52 (range, 40-69), 10 (range, 4-24) and 92.2 (range, 56-119.6) Gy, respectively. Only 1 patient developed local failure, with a median follow-up of 11 months (range, 1-59 months). Therefore, the 12-month progression-free survival rate for 67 sites was 96.8%. The overall survival rates at 12 and 36 months were 75.8 and 30.2%, respectively. A total of 2 patients developed grade >2 toxicities, including grade 3 mucositis and grade 4 pericardial effusion. Our results demonstrated that radical RT using modern techniques is highly feasible, achieves excellent local control, and may be an effective treatment option for refractory sarcoma.