Unstratified chemotherapy for non-metastatic osteosarcoma of the extremities in children

Background and Purpose: The superiority of changing postoperative chemotherapy of osteosarcoma based on histological response of the primary tumor over non-tailored chemotherapy has not been confirmed. This multicenter study evaluated the effectiveness of an intensive unstratified chemotherapy regimen in Taiwanese children with osteosarcoma. Methods: Fifty patients younger than 18 years of age with previously untreated non-metastatic osteosarcoma of the extremities were enrolled. Patients were treated with pre- and postoperative chemotherapy, and surgery. Definitive surgery was scheduled in week 7 and postoperative chemotherapy was uniform without stratification regardless of histologic response. Results: Chemotherapy toxicities were considerable, but manageable. Treatment delay and decreased dose-intensity were common. There was one treatment-related mortality. Forty three patients (86%) received limb salvage surgery and 14 patients (33%) had a good histologic response to preoperative chemotherapy. With a median follow-up of 47.1 months, the 7-year event-free and overall survival rates were 51.6%, respectively. Conclusions: This was the first multicenter study on the treatment of osteosarcoma from Taiwan. The results suggest that a non-tailored regimen may serve as an alternative treatment strategy in the management of osteosarcoma, particularly when histologic assessment of the tumor response is not available.