Ewing 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 parts of the body at the time of diagnosis. Complications may include a pleural effusion or paraplegia.It is a type of small round cell sarcoma. The cause of Ewing sarcoma is unknown. Most cases appear to occur randomly. Sometimes there has been a germline mutation. The underlying mechanism often involves a genetic change known as a reciprocal translocation. Diagnosis is based on biopsy of the tumor.Treatment often includes chemotherapy, radiation therapy, surgery, and stem cell transplant. Targeted therapy and immunotherapy are being studied. Five-year survival is about 70%. A number of factors, however, affect this estimate.James Ewing in 1920 established that the tumor is a distinct type of cancer. It affects about one in a million people per year in the United States. Ewing sarcoma occurs most often in teenagers and young adults and represents 2% of childhood cancers. Caucasians are affected more often than African Americans or Asians. Males are affected more often than females. Signs and symptoms
Ewing sarcoma is more common in males (1.6 male:1 female) and usually presents in childhood or early adulthood, with a peak between 10 and 20 years of age.
Treatment lengths vary depending on location and stage of the disease at diagnosis. Radical chemotherapy may be as short as six treatments at three-week cycles, but most people undergo chemotherapy for 6–12 months and radiation therapy for 5–8 weeks. Radiotherapy has been used for localized disease. The tumor has a unique property of being highly sensitive to radiation, sometimes acknowledged by the phrase "melting like snow", but the main drawback is that it recurs dramatically after some time.Antisense oligodeoxynucleotides have been proposed as possible treatment by down-regulating the expression of the oncogenic fusion protein associated with the development of Ewing sarcoma resulting from the EWS-ETS gene translocation. In addition, the synthetic retinoid derivative fenretinide (4-hydroxy(phenyl)retinamide) has been reported to induce high levels of cell death in Ewing sarcoma cell lines in vitro and to delay growth of xenografts in in vivo mouse models.In most pediatric cancers including sarcoma, proton beam radiation (also known as proton therapy) delivers an equally effective dose to the tumor with less damage to the surrounding normal tissue compared to photon radiation. Prognosis
Staging attempts to distinguish people with localized from those with metastatic disease. The most common areas of metastasis are the lungs, bone and bone marrow with less common areas of metastasis being the lymph nodes, liver and brain.