Ewings sarcoma arises from-

Ewing sarcoma and primitive neuroectodermal tumors (PNETs) are primary malignant small round cell tumors of bone and soft tissue. They share ceain molecular features and are best viewed as variants of the differentiation and clinical features. PNETs demonstrate clear neural differentiation, whereas Ewing sarcomas are undifferentiated.Ewing's sarcoma is a type of cancer that forms in bone or soft tissue. Symptoms may include swelling and pain at the site of the tumor, fever, and a bone fracture. The most common areas where it begins are the legs, pelvis, and chest wall. In about 25% of cases, the cancer has already spread to other pas of the body at the time of diagnosis. ref : Robbins Basic Pathology, 9E,page-780