NKX2-2 was positive in 9 (75%) mesenchymal chondrosarcomas, 8 (80%) olfactory neuroblastomas, 1 CIC-DUX4 sarcoma, 1 poorly differentiated synovial sarcoma, 1 neuroblastoma, 2 unclassified round cell sarcomas, and 3 small cell carcinomas.     ///    "Nonetheless, NKX2-2 may be helpful to distinguish Ewing sarcoma from some histologic mimics including CIC-DUX4 and BCOR-CCNB3 sarcomas. "    ///    "We evaluated whole-tissue sections from 270 cases: 40 Ewing sarcomas (4 with atypical/large cell features), 20 CIC-DUX4 sarcomas, 5 BCOR-CCNB3 sarcomas, 9 unclassified round cell sarcomas, 10 poorly differentiated synovial sarcomas, 10 lymphoblastic lymphomas, 10 alveolar rhabdomyosarcomas, 10 embryonal rhabdomyosarcomas, 10 Merkel cell carcinomas, 10 small cell carcinomas, 20 melanomas, 5 NUT midline carcinomas, 10 Wilms tumors, 10 neuroblastomas, 10 olfactory neuroblastomas, 12 mesenchymal chondrosarcomas, 10 angiomatoid fibrous histiocytomas, 10 clear cell sarcomas, 5 gastrointestinal clear cell sarcoma-like tumors, 5 desmoplastic small round cell tumors, 10 extraskeletal myxoid chondrosarcomas, 10 soft tissue and cutaneous myoepitheliomas, and 19 myoepithelial carcinomas. "