Long-term Survivors of Childhood Ewing Sarcoma: Report From the Childhood Cancer Survivor Study

Abstract

The survival of Ewing sarcoma (ES) patients has improved since the 1970s but is associated with considerable future health risks. The study population consisted of long-term (> or =5-year) survivors of childhood ES diagnosed before age 21 from 1970 to 1986. Cause-specific mortality was evaluated in eligible survivors (n = 568), and subsequent malignant neoplasms, chronic health conditions, infertility, and health status were evaluated in the subset participating in the Childhood Cancer Survivor Study (n = 403). Outcomes were compared with the US population and sibling control subjects (n = 3899). Logistic, Poisson, or Cox proportional hazards models, with adjustments for sex, age, race/ethnicity, and potential intrafamily correlation, were used. Statistical tests were two-sided. Cumulative mortality of ES survivors was 25.0% (95% confidence interval [CI] = 21.1 to 28.9) 25 years after diagnosis. The all-cause standardized mortality ratio was 13.3 (95% CI = 11.2 to 15.8) overall, 23.1 (95% CI = 17.6 to 29.7) for women, and 10.0 (95% CI = 7.9 to 12.5) for men. The nonrecurrence-progression non-external cause standardized mortality ratio (subsequent non-ES malignant neoplasms and cardiac and pulmonary causes potentially attributable to ES treatment) was 8.7 (95% CI = 6.2 to 12.0). Twenty-five years after ES diagnosis, cumulative incidence of subsequent malignant neoplasms, excluding nonmelanoma skin cancers, was 9.0% (95% CI = 5.8 to 12.2). Compared with siblings, survivors had an increased risk of severe, life-threatening, or disabling chronic health conditions (relative risk = 6.0, 95% CI = 4.1 to 9.0). Survivors had lower fertility rates (women: P = .005; men: P < .001) and higher rates of moderate to extreme adverse health status (P < .001). Long-term survivors of childhood ES exhibit excess mortality and morbidity.