Extracorporeal irradiation for malignant bone tumors

PURPOSE: Extracorporeal irradiation (ECI) has been used selectively in the management of primary malignant bone tumors since 1996. We report our techniques for ECI and the short-term oncologic and orthopedic outcomes. METHODS AND MATERIALS: Sixteen patients with primary malignant bone tumors were treated with ECI from 1996 to 2000. The median age was 14 years. The histologic diagnoses were Ewing's sarcoma (11), osteosarcoma (4) and chondrosarcoma (1). The treated sites were femur (7), tibia (4), humerus (2), ilium (2), and sacrum (1). Following induction chemotherapy in Ewing's sarcomas and osteosarcoma, en bloc resection of the tumor and tumor-bearing bone was performed. A single dose of 50 Gy was delivered to the bone extracorporeally using either a linear accelerator (9 cases) or a blood product irradiator (7 cases). The orthopedic outcome was recorded using a standard functional scale. RESULTS: At a median follow-up of 19.5 months, there were no cases of local recurrence or graft failure. One patient required amputation due to chronic osteomyelitis. For the 10 patients with follow-up greater than 18 months, the functional outcomes were graded good to excellent. CONCLUSION: The short-term oncologic and orthopedic results are encouraging and suggest that ECI provides a good alternative for reconstruction in limb conservative surgery in selected patients. This technique should only be used in a multidisciplinary setting, where careful follow-up is available to assess the long-term outcomes.