Ewing’s Sarcoma

Ewing sarcoma (ES) belongs to the family of the small, round, and blue cell tumors. With a reported incidence of around 1 to 3 per million cases-year, Ewing sarcoma should be considered as a rare cancer. Nonetheless, it is the third most frequent primary sarcoma of bone after osteosarcoma and chondrosarcoma, and represents the second most common primary malignant tumor of bone in children and adolescents. It is characterized by a chromosomal translocation between chromosomes 11 and 22; t(11;22)(q24;q12). This translocation is present in 85% of cases and nowadays is considered pathognomonic for this disease. Patients usually complain of pain in the absence of relevant trauma. Clinical and laboratory systemic symptoms that can be associated with ES sarcoma are fever, leukocytosis, and increase of erythrocyte sedimentation rate. Positivity of this triad of symptoms makes osteomyelitis a relevant differential diagnosis. The radiographic appearance has been described as a permeative lesion with an aggressive behavior and poorly defined borders. MRI will better define the tumor size volume and intramedullary extension. The treatment protocol consists of three phases: neoadjuvant chemotherapy, local therapy in the form of either surgical resection or radical radiation therapy, and then adjuvant postoperative chemotherapy.