Is Race an Independent Predictor of 5-Year Survival in Patients with Primary Malignant Bone Tumors?

Abstract

Background In the United States, socioeconomic status (SES), race, and ethnicity are factors used to predict adverse outcomes in various carcinomas as well as in soft tissue sarcoma. However, existing evidence is unclear if race is an independent predictor of overall survival in common primary malignant bone tumors, including Ewing sarcoma, osteosarcoma, and chondrosarcoma. Methods This is a retrospective analysis of the National Cancer Database (NCDB) of patients diagnosed with primary Ewing sarcoma, osteosarcoma, and chondrosarcoma between 1998 and 2016. Race/ethnicity was divided into White, Black, Asian, and “Hispanic”. Baseline and treatment characteristics between groups were compared using Pearson’s chi-square test for categorical variables and analysis of variance (ANOVA) for continuous variables. Long-term survival for each group was evaluated with the Kaplan-Meier (KM) method with comparisons between races based on the log-rank test. A multivariable Cox proportional hazard model was used to predict variables associated with lower overall survival. Results Black Ewing sarcoma patients had significantly poorer overall survival than did White, Asian, or Hispanic patients (p < 0.001) with a KM 5-year survival of 48.2% vs 61.0% vs 68.3% vs 63.0%, respectively, and a 123.5% (HR: 2.235, p = 0.009) higher independent likelihood of mortality in a multivariate analysis. Independent predictors of overall survival for Ewing sarcoma, osteosarcoma, and chondrosarcoma included older age (HR: 1.029, p < 0.001; HR: 1.020, p < 0.001; HR: 1.034, p < 0.001), more advanced cancer stage (HR: 3.315, p < 0.001; HR: 6.167, p < 0.001; HR: 10.201, p < 0.001), and positive surgical margins (HR: 1.679, p = 0.001; HR: 1.540, p < 0.001; HR: 1.992, p < 0.001), respectively. A significant racial disparity in survival for Black patients with Ewing sarcoma was identified. Conclusions Our study identifies a significant racial disparity in survival for Black patients with Ewing sarcoma. Our study reinforces previously established literature about predictors of overall mortality for Ewing sarcoma, osteosarcoma, and chondrosarcoma populations, while also providing new insight into the role of race, cancer-specific factors and treatment, and SES on long-term survival.