RESUMO
INTRODUCTION: This retrospective study was conducted to identify the characteristics of paediatric high-grade osteosarcoma and define its prognostic factors. METHODS: We identified paediatric patients (aged <19 years at diagnosis) diagnosed with high-grade osteosarcoma from 1 January 2009 to 31 December 2018 in two hospitals in Hong Kong, then retrospectively evaluated their medical records to identify prognostic factors. RESULTS: In total, 52 patients were included in this study (22 girls, 42.3%). Femoral tumour was the most common form of osteosarcoma. Most patients (78.8%) had localised disease at diagnosis. The lung was the most common site of metastasis. Almost half (n=23, 46.9%) of the patients showed a good response to chemotherapy (ie, chemonecrosis >90%). Most patients (n=40, 80%) underwent limb-salvage surgery. The event-free survival and overall survival rates were 55.8% and 71.2%, respectively. Prognostic factors independently associated with poor event-free survival and poor overall survival were the presence of metastasis at diagnosis, poor tumour chemonecrosis, and the need for amputation. CONCLUSION: This multicentre review of paediatric high-grade osteosarcoma showed that the baseline patient demographics, event-free survival, and overall survival in Hong Kong were similar to previous findings in other countries. Patients with metastatic disease at diagnosis and poor chemonecrosis had worse survival outcomes. Molecular analyses of genetic abnormalities may help to identify targeted therapies in future studies.