Primary Ewing's sarcoma affecting the central nervous system: a review and proposed prognostic considerations

Ewing's sarcoma (ES) is a part of a larger family of round blue cell tumors, which occasionally manifest as osseous or extraosseous lesions adjacent to or within the central nervous system (CNS). While a large body of literature exists on ES of bone, data are lacking on tumors with cranial or spinal components that affect the CNS. Here, we perform a systematic review of the literature and summarize the best available evidence on diagnosis, treatment and outcomes of ES affecting the CNS with emphasis on the breadth of clinical presentations, diagnostic tools and emerging management options for these rare and challenging lesions. We include a review of known prognostic factors and propose several new considerations for prognostication of ES affecting the CNS.