Pediatric Blood & CancerEwing Sarcoma in Infants and Children Under 2 Years of Age: A French Retrospective Study

⚠️ Small Study / Early Comparative Evidence

Ewing sarcoma before age 2 is exceptionally rare, leaving treatment decisions dependent on limited evidence and adaptation of protocols developed for older children. Investigators examined 17 French patients treated from 1988 through 2015 and compared their presentation, treatment, toxicity, and outcomes with 1,245 patients aged 2 to 18 years. Infants received weight- or age-adjusted chemotherapy and underwent surgery more often than radiotherapy. Five-year disease-free and overall survival were both 88.2%, but the very small cohort and evolving treatment era restrict generalizability.

Clinical Considerations

• Extraosseous disease was more common in infants than older patients, occurring in 24% versus 8% of cases.
• Sixteen of 17 infants achieved complete remission after chemotherapy and local treatment; two subsequently experienced localized recurrence.
• Five-year DFS and OS were both 88.2%, with wide 95% confidence intervals of 65.7% to 96.7%.
• Surgery alone was used in 82% of infants, while radiotherapy with or without surgery was used in 18%, versus 44% among older patients.
• Acute chemotherapy toxicity was substantial but broadly expected. Grade 4 hematologic toxicity occurred in 91% of infants evaluated under the EE99 protocol.
• Late effects affected several organ systems, including orthopedic, renal, cardiac, pulmonary, dental, growth, and pubertal outcomes. Fertility and later-emerging malignancy risks remain incompletely assessed.

Practice Applications

• Recognize that age- and weight-adjusted chemotherapy can retain treatment intensity, but this retrospective series does not define an optimal infant regimen.
• Prioritize multidisciplinary local-control planning, particularly when complete resection cannot be achieved and radiotherapy carries substantial developmental consequences.
• Monitor long-term cardiac and renal function, especially after anthracycline, ifosfamide, or high-dose chemotherapy exposure.
• Integrate orthopedic, growth, dental, endocrine, and fertility surveillance into survivorship care as patients progress through adolescence and adulthood.
• Interpret the favorable survival cautiously because only 17 infants were included and treatments changed across the 27-year enrollment period.