Extraskeletal Ewing Sarcoma- A Case Report with Review of Literature

Extraskeletal Ewing sarcoma is a rare malignant soft tissue tumor. It belongs to a group of small round blue cell tumors known as the Ewing sarcoma family of tumors, with common histological and genetic features. Mainly encountered in adolescents and young adults, it commonly develops in the extremities (36%) of patients and, in others, arises in central locations (commonly paravertebral regions).The Presnting case of a 13-year-old female presented to the private clinic after a history of trivial trauma to the back; her family noticed amass in the left paravertebral area, and the mass was painless. During the physical examination, the mass measured about 5*5 cm. It was not tender, hard inconsistency and fixed to the ribs, and the skin was not tethering; a radiological examination showed a mass of about 8*10*12 cm. involving three intercostal spaces and their ribs bulging into the thoracic cavity. A tru cut biopsy and histopathological examination revealed round cell tumors (Extraskeletal Ewing sarcoma) confirmed by immunohistochemical marker CD99 strongly positive. The patient was treated by chemotherapy and surgery, and she responded well to treatment. After eight cycles of chemotherapy, the patient was referred to the surgeon for resection of the residual mass; a left posterolateral thoracotomy was done, and the remnant of the mass was mainly fibrous tissue removed with 10 cm. of the posterior part of the 8th rib removed and sent again for histopathological examination, then the patient sent to an oncologist for prophylactic chemotherapy the patient followed for 5 months with no evidence of recurrence