Euro-EWING99 long-term analysis defines outcomes in 3,395 patients with Ewing sarcoma

Five-year progression-free and overall survival were 55.4% and 64.6%, with metastatic status and histologic response remaining major prognostic factors.

KEY POINTS

  • Euro-EWING99 was a large international prospective study enrolling patients younger than 50 years with Ewing sarcoma between 1999 and 2015. The long-term analysis included 3,395 patients.
  • At presentation, 2,267 patients had localized disease, 614 had pleuropulmonary metastatic disease, and 514 had extrapulmonary metastases.
  • Induction therapy consisted of six courses of VIDE—vincristine, ifosfamide, doxorubicin, and etoposide—followed by local therapy with surgery and/or radiotherapy and risk-adapted consolidation.
  • Ninety-eight percent of patients received at least four neoadjuvant VIDE courses, demonstrating high treatment delivery across the large international cohort.
  • With median follow-up of 7.2 years, progression-free survival for the overall population was 60.2% at three years and 55.4% at five years.
  • Overall survival was 72.6% at three years and 64.6% at five years, establishing long-term outcome benchmarks across the complete Euro-EWING99 population.
  • In addition to metastatic status at diagnosis, patient age, tumour volume, and histologic response to neoadjuvant therapy remained major prognostic factors for progression-free and overall survival.

CLINICAL TAKEAWAY

Euro-EWING99 confirms that Ewing sarcoma prognosis cannot be reduced to metastatic versus localized disease alone: tumour burden, age, and especially response to induction therapy remain critical. The study is primarily a long-term prognostic benchmark rather than evidence for a new radiotherapy strategy.

SOURCE

Journal of Clinical Oncology