TNFRSF21 and rhabdomyosarcoma: We further evaluated DR6 expression based on histologic subtypes, including myogenic sarcoma (22 leiomyosarcoma and 2 rhabdomyosarcoma), liposarcoma (n = 11), bone sarcoma (4 osteosarcomas and 1 Ewing sarcoma), peripheral nerve sheath tumor (n = 4), synovial sarcoma (n = 6), angiosarcoma (n = 5), and undifferentiated sarcoma (5 pleomorphic undifferentiated, 3 undifferentiated uterine, 6 undifferentiated-NOS, and 3 extra-skeletal myxoid chondrosarcomas) (Figure 3D).