ESMO Minimum Clinical Recommendations for diagnosis, treatment and follow-up of Ewing's sarcoma of bone.

• Patients with radiological findings suggesting a bone sarcoma should be referred without prior biopsy to a centre with particular bone sarcoma experience. Ewing’s sarcoma is usually dominated by a large soft tissue component. Histological diagnosis is made by needle biopsy or open surgical biopsy. The Ewing family of tumours (ES) includes classical Ewing’s sarcoma and primitive neuroectodermal tumour (PNET), and these are treated identically. ES are rare tumours arising in the bone marrow from primitive neural elements and constitute ∼10% of bone sarcomas. ES can be distinguished immunohistochemically from other pediatric ‘blue tumours’ by expression of the MIC2 gene. Detection of the translocation t(11;22)(q24;q12) by cytogenetics or PCR is diagnostic (present in >90%).