Primary intradural extramedullary Ewing sarcoma: Review of literature and update for a standard protocol

Ewing sarcoma (ES) is a rare, undifferentiated, and malignant mesenchymal tumor primarily affecting children and young adults. It typically presents as a lytic bone lesion located in the diaphysis of long bones or the flat bones of the pelvis, with the most common sites of metastasis being the lungs, skeletal system, and bone marrow. Primary intradural extramedullary Ewing sarcoma (IEES) is extremely rare, and its clinical presentation often overlaps with that of other spinal tumors, which can complicate diagnosis and treatment. We report a case of a young male patient, who was admitted with primary intradural extramedullary ES in the lumbar region. Magnetic resonance imaging revealed a large intradural, extramedullary mass extending from L2 to L5, with moderate contrast enhancement, initially suggesting a diagnosis of ependymoma. Consequently, the patient underwent an L2–L5 laminotomy with partial resection of the tumor. Histopathological and immunohistochemical analyses confirmed the diagnosis of IEES. After a multidisciplinary collegial evaluation of the case, the patient underwent adjuvant treatment with systemic chemotherapy. IEES is a rare condition, but it still merits consideration as a differential diagnosis of spinal tumors. Despite advances in treatment modalities, the literature review underscores the risk of local recurrence and distant metastasis, drawing attention to the importance of ideally pursuing radical surgery and effective oncologic treatment.