Unusual presentation of metastatic Ewing sarcoma to the ovary in a 13 year-old: a case report and review.

Ewing sarcoma (ES) is the second most common bone malignancy in children and adolescents. Together with primitive neuroectodermal tumors (PNET), ES comprises the PNET/ES family. Metastasis is present in about 25% of patients at diagnosis and is most commonly found in the lung and bones. Primary PNET/ES of the ovary has been reported in many adult cases; however, secondary occurrences are rare. Here we present the clinical course of a 13-year-old patient with metastatic ES to the ovary without involvement of any other sites. To our knowledge, this is the second reported pediatric case of metastatic ES to the ovary.