Unusual Manifestation of Extraosseous Ewing Sarcoma: Report of 3 Cases.

Ewing sarcoma (ES), described as a diffuse endothelioma of the bone, is divided into two categories: osseous and extraosseous, which mainly affects adolescents. Extraosseous Ewing Sarcomas (EES) are rare tumors originating from soft tissues. Their clinical presentation depends mainly on the primary location of the tumor and are highly chemosensitive and radiosensitive. The purpose of this study was to describe the clinical characteristics and outcomes of 3 children with EES and uncommon presentation treated in our Unit. The diagnosis of EES was confirmed by biopsy and cytogenetic analysis with fluorescence in situ hybridization (FISH). Surgical excision was planned as primary treatment, followed by adjuvant chemotherapy according to EURO-E.W.I.N.G protocol. To date, all patients are alive, 1, 3 and 4 years after completion of treatment, with no signs of recurrence or metastasis.