FLI1 and Ewing sarcoma: While the DSRCT is unique for harboring the EWSR1::WT1 gene fusion, its differential diagnosis also has specific genetic signatures: PAX3::FOXO1, PAX7::FOXO1, or PAX3::AFX gene fusions for alveolar rhabdomyosarcoma, EWSR1::FLI1, EWSR1::ERG, EWSR1::FEV, EWSR1::ETV1, EWSR1::E1AF, EWSR1::ZSG, or FUS::ERG gene fusions for Ewing sarcoma/peripheral neuroectodermal tumor, and CIC::DUX44 or BCOR::CCNB35 gene fusions for undifferentiated round cell sarcomas [54].