Posterior fossa ependymoma with preoperative cerebrospinal metastases: a case report with literature review.

Background: Adult posterior fossa ependymomas (PF-EPN) with preoperative cerebrospinal metastases are extremely rare. Only 3 cases have been reported in previous literature.

Case Presentation: A case of a 32-year-old male patient complained of headaches for three months. Pure tone audiometry showed a slight decrease in bilateral hearing. Auditory evoked potential indicated that the hearing on the left was slightly weaker than that on the right. Magnetic resonance imaging (MRI) revealed a primary tumor arising within the fourth ventricle and metastasizing to bilateral cerebellopontine angle (CPA), the third ventricle, the left lateral ventricle, T1, L1-2 and L5. A gross total resection (GTR) was performed on the lesion located in the left CPA. The histological examination showed a papillary ependymoma (WHO grade II). Immunohistochemical staining for H3K27me3 showed that nuclear positivity in more than 80% of cells. No NF2 mutation was observed. No progression was found during a 24-month follow-up.

Conclusions: Our data indicate that preoperative multiple metastases in adult PF-EPN are extremely rare. This kind of disease usually has a low WHO grade and a favorable prognosis. GTR should be achieved when feasible and patients need a long-term follow-up with MRI.