Carbon ion radiotherapy for localized primary sarcoma of the extremities: Results of a phase I/II trial

Purpose To determine the effectiveness of carbon ion radiotherapy (CIRT) for localized primary sarcomas of the extremities in a prospective study. Patients and materials From April 2000 to May 2010, 17 (male/female: 12/5) patients with localized primary sarcoma of the extremities received CIRT. The median age was 53years (range: 14–87years). Nine patients had primary diseases and eight had recurrent diseases. Of the 17 patients, eight refused amputation, and the remaining nine refused surgical resection. Tumors were located in the upper limbs in four patients and lower limbs in 13. Histological diagnosis was osteosarcoma in three patients, liposarcoma in two, synovial sarcoma in two, rhabdomyosarcoma in two, pleomorphic sarcoma in two, and miscellaneous in six. The CIRT dose to the limb was 52.8GyE for one patient, 64GyE for three, 70.4GyE for 13 in 16 fixed fractions over 4weeks. Records were reviewed and outcomes including radiologic response, local control (progression-free), and survival were analyzed. Results The median follow-up was 37months (range: 11–97months). Radiological response rate was 65% (PR in 11, SD in 5, and PD in 1). The local control rate at 5years was 76%. The overall survival rate at 5years was 56%. Of the 17 patients, 10 survived without disease progression. Four patients had local recurrences, one was salvaged by repeated CIRT and the other three died due to systemic diseases. Distant failure was observed in six patients. One patient suffered from femoral fracture (grade 3) and received surgical fixation 27months after CIRT. No other severe reactions (grade 3) were observed. Conclusions CIRT is suggested to be an effective and safe treatment for patients who refuse surgery for localized primary sarcomas of the extremities.