[Value of intraoperative electron radiation therapy in the treatment of malignant bone or soft tissue tumors around the joints].

Objective: To evaluate the value of intraoperative radiation therapy with electrons (ELIOT) in treatment of malignant bone or soft tissue tumors around the joints.

Methods: From October 2008 to April 2012, nineteen patients with malignant bone or soft tissue tumors around the joints were treated with ELIOT. The tumors were located around the knee joint in 8 patients, around the hip joint in 6 patients, around the elbow joint in 4 patients and around the shoulder joint in one patient. All of the patients underwent limb salvage surgeries. R0 resections were performed in 18 patients, while R1 resection was performed in one patient. The doses of intraoperative radiation ranged from 10 Gy to 22 Gy. The median dose was 19 Gy. More than one ELIOT fields were used in 10 patients because of the large tumor size.

Results: Seven patients suffered wound complications. No grade ≥ 3 acute toxicities were observed. One patient developed radiation ulcer and arterial fistula 15 months after surgery and ELIOT, and resulted in amputation finally (grade 4 late toxicity). The mean Musculoskeletal Tumor Society (MSTS) 93 score was 26.26 ± 4.04 (87.5% ± 13.5%), with excellent to good extremity functions in 18 patients (94.7%). Four patients had local recurrences. The estimated locoregional control rates at 1, 2, and 3 years were 81.9%, 73.7%, and 73.7%, respectively. Seven patients died of the diseases. The estimated overall survivals of the entire group of patients at 1, 2, and 3 years were 76.3%, 61.2%, and 51.0%, respectively.

Conclusions: ELIOT is a safe and well-tolerable technique and could be widely used for patients with malignant bone or soft tissue tumors around the joints with acceptable rates of acute and late toxicity. There is positive significance for controlling the tumor local recurrence, preserving the joint function and improving survival quality.