Primary Ewing Sarcoma in Spinal Epidural Space: Report of Three Cases and Review of the Literature

Ewing sarcoma (ES) is the most common malignant bone tumor in children younger than 10 years of age. Extraosseous ES (EES) arising from the spinal epidural space is extremely rare. We aimed to report herein three cases of primary spinal epidural EES and to review the related literature. We report our experience with three cases of primary spinal epidural EES in a single institution (aged 34, 14, and 65 years). The patients were admitted with complaints of weakness of the lower extremities and urinary retention. Magnetic resonance imaging (MRI) showed an epidural mass with cord compression at T4-T6, L2-L3 and T7-T8 levels, respectively. All three patients underwent laminectomy; total resection of the epidural mass was performed in two patients and gross total resection in one patient. Immunohistochemical examinations revealed ES. All patients underwent chemotherapy and radiotherapy after surgery. No evidence of recurrence or metastasis was detected after 18 and 16 months, respectively, for the first two cases. In the third patient, gross total resection was performed due to tumor infiltration and invasion to the surrounding tissue, and residual tumor in the surrounding tissue was noted on MRI for the 14-month follow-up period.