Specific proteins related to skeletal muscle are helpful to distinguish other tumors, including actin, myosin, desmin, Myglobin, Z-band protein, MyoD and mygenin.5 The pathological types of RMS in children are mainly embryonal rhabdomyosarcoma (ERMS) and alveolar rhabdomyosarcoma (ARMS); grape-shaped type and spindle cell type are variant of ERMS, and polymorphous cell type is rare. The gene discussed is MYOD1; the disease is embryonal rhabdomyosarcoma.