Abstracts

Rationale: Supratentorial cortical ependymoma (CE) is rare, with less than 10 cases reported. All reported cases suggest the presenting symptom is epilepsy. Further, the relationship to the recently described angiocentric glioma (AG) is still unclear; however there appear to be distinct differences. Methods: Between 1997 and 2009, we identified 202 cases of ependymoma at our institution; there were 49 cases of supratentoral tumors. From this, 9 cases of CE were retrospectively reviewed from our institutional experience. Results: Tumors arose from the frontal (n=5), parietal (n=3), and occipital (n=1) lobes. Interestingly, no tumor occurred in the temporal lobe, despite its reported association with seizures. Mean Age at presentation was 26.8 ± 6.2 years, and age at resection was 35.7 ± 5.3 years. Average size was 16 ± 14 cm3. Seizures were the presenting symptom in 78%. CE radiographic appearance is distinctive, with popcorn enhancement and heterogeneous appearance. Gross total resection (GTR) was achieved in 8 of 9 tumors. Six were WHO grade II, and three were grade III ependymoma. Two recurred locally after imaging confirmed GTR, both grade III. Mean follow up since surgery for all CE was 61.5 ± 38 months. Seventy-one percent of patients presenting with seizures achieved an Engel grade one outcome. Conclusions: This large series of cortical ependymomas demonstrates that, contrary to reported cases, not all tumors are low grade and cured with surgery. Further, not all tumors present with seizures. Moreover, despite its high association with epilepsy, it is distinctly absent from the temporal lobe.