A New Survival Score for Patients ≥65 Years Assigned to Radiotherapy of Bone Metastases

Abstract

Survival scores are important for personalized treatment of bone metastases. Elderly patients are considered a separate group. Therefore, a specific score was developed for these patients. Elderly patients (≥65 years) irradiated for bone metastases were randomly assigned to the test (n = 174) or validation (n = 174) cohorts. Thirteen factors were retrospectively analyzed for survival. Factors showing significance (p < 0.05) or a trend (p < 0.06) in the multivariate analysis were used for the score. Based on 6-month survival rates, prognostic groups were formed. The score was compared to an existing tool developed in patients of any age. In the multivariate analysis, performance score, tumor type, and visceral metastases showed significance and gender was a trend. Three groups were designed (17, 18–25 and 27–28 points) with 6-month survival rates of 0%, 51%, and 100%. In the validation cohort, these rates were 9%, 55%, and 86%. Comparisons of prognostic groups between both cohorts did not reveal significant differences. In the test cohort, positive predictive values regarding death ≤6 and survival ≥6 months were 100% with the new score vs. 80% and 88% with the existing tool. The new score was more accurate demonstrating the importance of specific scores for elderly patients.