Age-related real-world treatment patterns and outcomes of localised, high-grade osteosarcoma

Introduction: There is currently no consensus regarding the standard treatment for osteosarcoma arising in middle-aged and older patients. We aimed to evaluate real-world treatment patterns and oncological outcomes using a nationwide Japanese database and to clarify optimal age-adapted treatment strategies. Methods: A total of 871 patients with localised, high-grade osteosarcoma registered between 2011 and 2020 in the Japanese Bone and Soft Tissue Tumour Registry were analysed. Treatment patterns and disease-specific survival (DSS) were evaluated according to age groups (≤ 40 years, n = 615; 41-64 years, n = 154; and ≥ 65 years, n = 102). Results: < 0.001). DSS was significantly superior in patients undergoing guideline-concordant treatments (wide/radical resection with perioperative chemotherapy) regardless of age. In patients aged > 40 years who underwent guideline-concordant treatments, DSS did not differ between primary chemotherapy and upfront surgery. Conclusion: Wide/radical resection combined with perioperative chemotherapy remains the mainstay of treatment regardless of age in osteosarcoma management. The optimal sequencing of chemotherapy and surgery warrants a prospective international collaborative study.