ES is caused by pathognomonic translocations juxtaposing the EWS RNA binding protein 1 (EWSR1) gene with one of E26 transformation-specific (ETS) genes, with EWSR1 being most commonly fused with friend leukemia integration 1 (FLI1) or ETS-related gene (ERG) (9, 10). This evidence concerns the gene ERG and Ewing sarcoma.