Inguinal lymph nodal metastasis of myxopapillary ependymoma confirmed by fine-needle aspiration cytology, biopsy, and immunohistochemistry: case report.

Ependymoma (EP) rarely metastasizes outside the central nervous system. Inguinal nodule metastasis of EP more than 10 years after surgical resection and radiotherapy is extremely rare. We report a man aged 38 years who underwent surgery for lumbosacral myxopapillary EP at the age of 22 years and was treated with several cycles of radiotherapy. The patient was reoperated for residual tumor and received two complete cycles of radiotherapy for 11 years. Biopsies were always diagnosed as myxopapillary EP. Five years after the last surgical excision, the patient developed abdominal pain and inguinal lymphadenopathy. Biopsy was performed by fine-needle aspiration and was proven malignant epithelial neoplasm with a myxoid background, was diagnosed as metastasis of EP. Biopsy showed an anaplastic EP grade III. EP is often recurrent at the primary site but can seed on the entire cerebrospinal axis. We describe the clinical features of this rare lesion and particularly emphasize the need for long-term follow-up, for more than 10 years after the initial treatment, in patients with EP and malignant transformation after radiotherapy.