Abstract
BACKGROUND: Pleomorphic xanthoastrocytomas (PXAs) are rare brain tumors that are often associated with seizures. There are limited data characterizing epilepsy phenotypes in relation to PXA tumor biology and survival outcomes. METHODS: This is a retrospective observational study of 35 patients with PXA who received treatment at the University of Pennsylvania or Dana-Farber Cancer Institute. Demographic and clinical features were assessed in PXA patients with or without seizures and with respect to seizure freedom following tumor resection. RESULTS: During their clinical course, 27 (77%) developed tumor-related epilepsy (TRE), with 25 (71%) initially presenting with a seizure. Compared to those without TRE, patients with TRE were more likely to have a BRAF-mutated PXA and less likely to have frontal lobe tumor localization. Patients with TRE who became seizure-free after the initial resection up to the time of progressive disease were found to have a lower age of seizure onset, smaller tumor diameter, and more likely to have BRAF-mutated tumors compared to those who were not seizure-free. However, following the last tumor resection and accounting for tumor recurrences, there were no significant differences in clinical features between those who were seizure-free and those who were not. Overall survival was 88% after 5 years and 59% after 10 years, with similar survival rates between patients with and without TRE. CONCLUSION: These findings indicate that BRAF-mutated and BRAF-wildtype PXAs have distinct epilepsy phenotypes. Further investigation of the interplay between tumor biology and seizures may help guide counseling and targeted therapeutic strategies for PXA-related epilepsy.