Myxopapillary ependymoma with anaplastic features: A case report with review of the literature.

Background: Myxopapillary ependymoma (MPE) with anaplastic features is extremely rare, with only three case reports in the literature.

Case Description: We report the case of a MPE with anaplastic features in a 24-year-old female who presented with a dominant lumbar mass along with intracranial and sacral metastases. Upon gross total resection of the dominant tumor located at L2-L3, it appeared to arise from the filum terminale, and had a solid component in addition to soft or necrotic areas. Histologically, the tumor was composed of the two classic components of MPE: (1) low-grade ependymal cells surrounding blood vessels, producing the papillary appearance and (2) perivascular myxoid material between blood vessels and ependymal cells, creating the myxopapillary appearance. The high-grade anaplastic component showed hypercellularity, brisk mitotic rate, and vascular proliferation, with frequent pleomorphic cells and atypical mitotic figures. It was positive for vimentin and glial fibrillary acidic protein (GFAP); negative for epithelial membrane antigen (EMA), CAM5.2, creatine kinase 7 (CK7), CK20; and the MIB-1 index (Ki-67) was 8-38%. Ten months after initial resection, follow-up magnetic resonance imaging revealed new lesions in (1) the hypothalamus, (2) the left pons, and (3) the left medial temporal lobe, which were treated with radiosurgery. Eight months later (18 months from initial surgery), the patient underwent thoracic laminectomy for a large leptomeningeal metastasis at T6 and T8.

Conclusion: The present case of MPE with anaplastic features is the fourth case on record in the medical literature.