Age as a Prognostic Factor in Patients with Ewing Sarcoma-The Polish Sarcoma Group Experience

Ewing sarcoma (ES) is a rare and aggressive disease that requires multidisciplinary treatment with the use of chemotherapy, radiotherapy, and surgery. Our retrospective study aimed to analyze the prognostic factors and treatment results in different age groups of patients. Between 1998 and 2018, 569 patients with ES were treated in two referral centers. The patients were divided into four age groups (≤10 years; 11-18 years; 19-25, and >25). The treatment results and prognostic factors were assessed for each group. For statistical analyses, we used the Chi2 test, the Kaplan-Meier estimator with a log-rank test, and the multivariate Cox model. Five-year overall survival (OS) rate was 56%. In the age subgroups: ≤10 years, 11-18 years, 19-25 years, and >25 years, the 5-year OS rates were 75%, 58%, 41%, and 52%, respectively. Favorable prognostic factors: female gender (p = 0.024), non-axial localization (p = 0.005), VIDE regimen (p < 0.001), and surgery as a local treatment (p < 0.001) dominated in the group ≤10 years. In multivariate analysis, male (HR = 1.53), axial localization (HR = 1.46), M1 status at presentation (HR = 2.64), and age > 10 years (HR = 2.29) were associated with shorter OS. The treatment results in ES are significantly better in children aged ≤10 years; the challenge is to provide therapy for adolescents and young adults. The diagnostics and treatment of ES patients must be provided in referral centers.