Abstract
PURPOSE: Primary Ewing sarcoma of the jaw is rare. The aim of this study was to describe new cases of primary Ewing sarcoma of the jaw and investigate reported prognostic factors of Ewing sarcoma in this series and treatment outcome. MATERIALS AND METHODS: Six patients with primary Ewing sarcoma of the jaw were treated at the Memorial Sloan Kettering Cancer Center (MSKCC) from 1992 through 2013. Clinical data, pathology reports, treatment prescribed, treatment regimens, outcome, and follow-up information were reviewed. RESULTS: Five of 6 patients were female and 5 cases were in the mandible. No patient presented with metastatic disease at diagnosis. All cases were positive for CD99, and 3 patients with genetic confirmation were positive for EWS-FLI1 fusion or EWSR1 gene rearrangement. All patients received induction multiagent chemotherapy and surgical resection and 2 patients received adjuvant radiotherapy. Total (grade IV) or nearly total (grade III) tumor necrosis in 3 of 5 patients (60%) assessed for histologic response to chemotherapy indicated intense sensitivity. All patients were alive and free of disease, with no history of local recurrence, at a median follow-up period of 6.5 years. CONCLUSION: Patients with primary Ewing sarcoma of the jaw have a good prognosis and metastasis is an uncommon occurrence at initial presentation.