EP14.05 LYMPH NODE METASTASIS IN MYXOPAPILLARY EPENDYMOMA WITHOUT CNS INVOLVEMENT: A RARE CASE REPORT AND THERAPEUTIC RESPONSE

Abstract BACKGROUND Myxopapillary ependymomas are rare neoplastic tumors originating from ependymal glial cells of the spinal cord. They rarely metastasize but may exhibit malignant behavior characterized by distant neural dissemination and spinal drop metastases. MATERIAL AND METHODS This is a retrospective case report of an adult patient with extra-neural metastatic myxopapillary ependymoma, including his diagnosis, treatment, and clinical outcomes. RESULTS We report the case of a 44-year-old male who presented with non-specific lower back pain for over 20 years, associated with gradual tumor growth. A near-total sacral resection was performed, and one year later, local recurrence was identified, without cerebrospinal fluid infiltration but with extra-neural metastases involving bilateral inguinal, pelvic, and retroperitoneal lymph nodes. Biopsy of an inguinal lymph node confirmed metastatic myxopapillary ependymoma. The patient underwent radiotherapy with a total dose of 36 Gy to the primary site and involved lymph nodes, followed by a sequential boost to 54 Gy to areas of gross disease, delivered with concurrent cisplatin. Adjuvant chemotherapy with cisplatin and etoposide (CDDP/VP-16) was administered. A PET-CT performed one year after treatment showed a partial response, with no further dissemination and good control of both neural and extra-neural disease. The patient remains under multidisciplinary follow-up and continues physiotherapy. CONCLUSION This case highlights a rare presentation of myxopapillary ependymoma with lymphatic metastasis in the absence of CNS dissemination. It underscores the potential efficacy of combined modality treatment, including systemic therapy, in controlling aggressive variants of this tumor.