Seizure characteristics and outcomes in patients with pleomorphic xanthoastrocytoma

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.

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.

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.

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.