Beyond the Spine: A Rare Case of Myxopapillary Ependymoma With Extraneural Metastases.

OBJECTIVE: Myxopapillary ependymoma (MPE) is a rare tumor of ependymal origin that commonly arises within the spinal canal. It is rather benign and slow-growing; however, it tends to recur along the central nervous system (CNS), usually after incomplete resection or tumor seeding due to surgical manipulation. Extraneural metastases of MPE are extremely rare, with only a few documented cases in the literature. CASE REPORT: We describe a case of a middle-aged female patient with sacrococcygeal MPE, which was initially misdiagnosed as a pilonidal cyst and subjected to surgical excision. Over the following years, she experienced three local recurrences in the sacrococcygeal region, which were treated with surgery and radiotherapy. Ten years after the initial excision, the patient complained of dyspnea and hemoptysis, and imaging studies revealed multiple right lung nodules. A core biopsy of a lung lesion was performed, and histopathology was consistent with metastatic MPE. The patient was started on chemotherapy with per os temozolomide and has not experienced disease progression for nearly 3 years. CONCLUSION: Extraneural metastases of MPE represent an exceptionally rare and diagnostically challenging entity and should be considered in patients with a history of MPE who present with distant lesions, even years after the initial diagnosis.