Supratentorial Cortical Ependymomas: A Retrospective Series of 13 Cases at a Single Center.

OBJECTIVE: Cortical ependymomas (CEs), supratentorial ependymomas that selectively involve the cerebral cortex, are relatively rare neoplasms that have not been extensively described. The purpose of our study was to identify the clinical features, radiologic characteristics, and treatment of a series of such tumors. METHODS: Thirteen patients with CEs from our hospital were included in this study. Epidemiologic characteristics, clinical features, imaging findings, treatment methods, and clinical outcomes were reviewed retrospectively. RESULTS: The patients consisted of 7 men and 6 women with mean age of 31.1 +/- 23.2 years (range, 4-74 years). The most common clinical manifestation was seizure (n = 11; 85%), followed by headache (n = 2; 15%). None of the tumors were incidentally detected. Eight CEs were located in the right hemisphere and 5 in the left side. The 2 most common tumor locations were the frontal (n = 5; 38%) and parietal lobe (n = 5; 38%). All patients underwent surgical resection. Gross total resection was achieved in 12 patients (92%), and subtotal resection was performed in 1 patient (8%). Ten of the 11 patients who presented with seizure are seizure-free after surgery (91% seizure-free rate). According to the World Health Organization classification system, 9 tumors (69%) were Grade II (ependymoma) and 4 (31%) were Grade III (anaplastic ependymoma). The mean follow-up was 52 months (range, 20-88 months). No recurrence was observed in patients with Grade II CEs. Of 4 patients with Grade III CEs, 2 (50%) suffered from tumor recurrence after initial treatment. CONCLUSIONS: CEs are a rare subset of supratentorial ependymomas that selectively involve the cerebral cortex. Most CEs are low grade and present with seizures. Anaplastic CEs show a greater recurrence rate and a relatively poor prognosis. Gross total resection with or without adjuvant radiotherapy is currently the optimal treatment for CEs. CEs seem to have a more favorable prognosis than other supratentorial ependymomas.