Conditional Survival and Predictors of Late Death in Patients With Ewing Sarcoma.

Purpose: Long-term survivors of Ewing sarcoma (EWS) are at considerable risk for future complications, including late relapse and death. Data on prognostic factors for late death in those who have survived beyond 5 years are lacking.

Methods: We conducted a retrospective cohort study using the Surveillance, Epidemiology, and End Results database. We obtained clinical features and outcome data on 1,351 patients with EWS who had survived 60 months or more. From these data, we performed univariate and multivariable analyses of overall survival (OS) using log-rank tests and Cox proportional hazard models.

Results: Of 1,351 patients in the cohort, there were 209 deaths, 144 (69%) of which were reported to be due to EWS. The OS for 5-year survivors at 10 years was 87.5% (95% confidence interval 85.4-89.3%). Univariate adverse prognostic factors for late death in 5-year survivors included age ≥ 18 years at initial diagnosis, male sex, and axial/pelvic primary site. Initial stage was not prognostic. Independent adverse prognostic factors for late death included black race (hazard ratio [HR] 2.16, P = 0.01), age ≥ 18 years at diagnosis (HR 2.02, P < 0.001), male sex (HR 1.43, P = 0.01), and axial/pelvic primary site (HR 1.43, P = 0.02).

Conclusions: The majority of late deaths in 5-year survivors are due to EWS. Black race, age ≥18 at diagnosis, male sex, and axial/pelvic primary site (but not stage at diagnosis) are independently associated with increased risk of late death.