505 Driver Mutations are Independent Predictors of Perioperative Seizure in Patients With Newly Diagnosed Meningiomas

INTRODUCTION: Seizure is a frequent presenting symptom for patients with newly diagnosed meningiomas. Though many risk factors have been identified, it is unknown whether driver mutations associated with meningioma development also portend increased risk for perioperative seizure in patients with meningiomas. METHODS: Tumor samples and clinical data were collected from an institutional tissue bank of patients who had a surgical resection of a primary meningioma between 1995 and 2018. The tumor samples were sequenced using next-generation targeted sequencing. Univariable models were used to select for relevant mutations with p-value < 0.20 for inclusion in the multivariate analysis. Multivariable models were built using selected variables and known clinical and demographic correlates of seizures. RESULTS: Of 146 patients with primary cranial meningiomas, 36 (24.7%) patients experienced preoperative seizures and 35 (24.0%) patients experienced postoperative seizures. A total of 16 (11.0%) patients developed both preoperative and postoperative seizures. With multivariable analysis, AKT1 mutation (OR = 4.26, p = 0.04), WHO grade 2 (OR = 12.94, p = 0.04) and convexity location (OR = 3.71, P =0.01) were associated with increased risk for preoperative seizures. Prior preoperative seizure (OR = 4.82, p = 0.003) were significantly associated with increased risk of developing postoperative seizure. For patients experiencing preoperative seizures, need for adjuvant radiation (OR = 28.5, p = 0.048) was significantly associated with increased risk of developing postoperative seizure. CONCLUSIONS: We identified AKT1 mutations, WHO grade 2, and convexity location as predictors of preoperative seizures. Prior preoperative seizures portended increased risk of postoperative seizure in patients with primary meningiomas. This analysis may help to inform which patients with newly diagnosed meningiomas may warrant antiepileptic drugs.