A novel scoring system based on post-radiotherapy changes in pain, performance status, and adverse events to stratify survival in bone metastases

Abstract

Abstract Although pain response has been associated with overall survival (OS) in palliative radiotherapy for bone metastases, the prognostic impact of integrating pain response with changes in performance status (PS) and treatment-related adverse events (AEs) remains unclear. This study aimed to investigate their combined effects on OS in this context. This study included 361 patients treated with palliative radiotherapy for bone metastases between January 2013 and October 2024, with 1-year OS as the primary endpoint. A composite score was developed by assigning weights to pain response, PS change, and AEs based on their respective 1-year OS rates (point = OS%/10). Internal validation used bootstrap resampling (1,000 iterations). Incremental prognostic value was assessed using Net Reclassification Improvement (NRI). The score (range, 4.8–15.8) significantly stratified OS (p < 0.001) with a C-index of 0.73. The composite model demonstrated superior discriminative performance compared with individual factor based on AUC comparisons (all p < 0.001). NRI analysis showed incremental prognostic value of the composite model over pain response (p = 0.017), PS change (p < 0.001), and AEs (p < 0.001). In conclusion, the scoring model incorporating pain response, PS changes, and AEs stratified OS-risk after palliative radiotherapy for bone metastases, providing incremental predictive value beyond pain response alone, but requires external validation before clinical application.