Poly (ADP‐ribose) polymerases (PARP) inhibitors have shown promising results in advanced STS, especially for Ewing sarcoma with EWS‐FLI1 or EWS‐ERG genomic fusions, and PARP inhibitors have synergy effect with some chemotherapy such as trabectedin while the mechanism is not fully known.7 This evidence concerns the gene EWSR1 and Ewing sarcoma.