Ewing sarcoma is a tumor of bone-derived precursor cells that occurs in bones and soft tissues, usually affecting children and adolescents. It is located in bone tissue such as legs, hips, ribs and spine. Symptoms such as pain, swelling, difficulty in joint movements, weakness, and weight loss may be observed in areas where tumor tissue develops. These tumors are mainly treated with combinations of chemotherapy and surgery, although in some cases radiotherapy or autologous stem cell transplantation may be added to the treatment plan