KIT and primitive neuroectodermal tumor: c-kit (CD117), a tyrosine kinase receptor, plays a crucial role in the development of melanogenesis, hematopoiesis, and gonadogenesis (Nocka et al., 1989), and is highly expressed in soft tissue sarcoma cells of neuroectodermic origin, such as ES and peripheral neuroectodermal tumors (PNET).