Primary Ewing's Sarcoma of Maxillary sinus: A Case Report.

Ewing's sarcoma are small round cell tumors belonging to Ewing's family of tumors and the second most common bone tumor seen in children. The most common affected sites are long bones of extremities followed by pelvis and ribs. Primary arising in head and neck region is uncommon and maxillary Ewing's sarcoma is rarely seen. Histologically it is one of many small round cell tumors found in children and therefore immunohistochemical and occasionally molecular studies are required to establish the diagnosis. Imaging features include aggressive bony destruction with periosteal reaction and associated soft tissue mass. Treatment of this tumor is a combination of induction chemotherapy followed by surgery and/or radiation with completion of chemotherapy due to aggressive nature and a high propensity for metastases. Our case is an 11year-old boy diagnosed with primary non-metastatic Ewing's sarcoma of left maxilla. The tumor was positive for CD 99 and FLI-1 and negative for CD 45 and Tdt on immuno-histocytochemical examination. The patient was treated with induction chemotherapy comprising of alternating 3 weekly cycles of Vincristine, Adriamycin and Cyclophosphamide with Etoposide and Ifosfamide. This was followed by radical conformal radiation to a dose of 55.8Gy in 31 fractions with good response. Keywords: Ewing's sarcoma, maxilla, IHC, chemotherapy, radiation.