Impact of Postoperative Radiotherapy on Survival in Primary Osteosarcoma: A population-based study

Abstract

PURPOSE To evaluate the impact of postoperative radiotherapy on survival in osteosarcoma patients. MATERIALS AND METHODS Total of 3218 participants aged 3–85 years with primary bone and joint osteosarcoma, primary site resection, and/or postoperative radiotherapy were enrolled from the Surveillance, Epidemiology, and End Results (SEER) database. Multiple imputations were utilized to fill in missing data, a directed acyclic graph was constructed to identify causal pathways, and propensity score matching at a ratio of 1:1 was employed to balance covariate characteristics. The Kaplan-Meier method was utilized to estimate survival rates, which were compared the rates using the Log-rank test, and univariate and multivariate analyses were performed using the Cox proportional hazards regression model. Subsequently, sensitivity analyses were conducted on the conclusions using subgroup analysis, competitive risk analysis, and complete dataset analysis. RESULTS A total of 430 patients in the analysis, with 215 in the Radiotherapy and Non-Radiotherapy groups. The 5-year overall survival rates (OS) were 39.1% and 47.1% in the two groups, and the 5-year cancer-specific survival rates (CSS) were 45.5% and 51.8%, respectively. Comparison of the survival rate between the two groups using the Log-rank test yielded non-significant differences (OS, χ² = 2.029, p = 0.154; CSS, χ² = 0.826, p = 0.363). Both univariate and multivariate analyses revealed no significant differencse in survival associated with radiotherapy. Moreover, the sensitivity analysis findings were consistent with these conclusions. CONCLUSION Postoperative radiotherapy for primary bone and joint osteosarcoma has not shown survival benefits, and its value should be reassessed in multidisciplinary management.