Characteristics and long-term outcomes of Ewing sarcoma patients in the Euro-EWING99 study

Euro-EWING99 was a multinational prospective study recruiting patients with Ewing sarcoma (EWS) between 1999 and 2015 younger than 50 years of age. The study assessed three different clinical questions through randomized trials. Patients received up to six 3-week courses of VIDE induction therapy (vincristine, ifosfamide, docorubicin, and etoposide), local therapy (surgery or radiotherapy) and different consolidation treatments according to clinical risk group and trial. A total of 3395 patients were included: 2267 with localized disease. 614 with pleuropulmonary metastases, and 514 wirh extrapulmonary metastases. Ninety-eight percent of the patients received at least four neoadjuvant VIDE courses. With a median follow-up of 7.2 years, the progression-free survival rate of the entire cohort was 60.2% at 3 years and 55.4% at 5 years, with overall survival rate of 72.6% at 3 years and 64.6% at 5 years. In addition to metastatic status at diagnosis, main prognostic factors included patient age, tumor volume, and histologic response. The authors conclude that this largest study of EWS patients to date may serve as a landmark paper for EWS.