Introduction: Epilepsy in the rare atypical and malignant meningiomas has been significantly under-studied. Our aim was to examine the rates, predictors, and epilepsy control in these two subtypes of meningiomas, and to analyze associations between clinical characteristics and seizure free survival (SFS) following surgical resection in an Asian population.
Methods: We retrospectively analyzed 102 patients with atypical or malignant meningiomas, treated between June 2001 and November 2009. Epilepsy occurring before and after the operation was reviewed. We compared demographic data and clinical characteristics including antiepileptic drugs (AEDs) treatment to extract potential risk factors for epilepsy.
Results: Pre-operative epilepsy occurred in 15 (14.7%) patients, and peri-operative occurred in 13 (12.7%). All cases of pre-operative epilepsy occurred with tumors located at the convexity or parasagittal area (P = .001), and was influenced by the presence of peritumor edema (odds ratio [OR] = 3.90; P = .027). Pre-operative epilepsy was predictive of peri-operative occurrence (OR = 4.94; P = .016). Twenty-one patients (20.6%) had post-operative epilepsy. SFS was significantly influenced by pre-operative epilepsy, AED use, and tumor location (P = .003, .036, and .002, respectively). Among 15 patients with pre-operative epilepsy, malignant meningiomas were associated with shorter SFS than atypical meningiomas (P = .001). Fifty one of 87 patients without pre-operative epilepsy had prophylactic AEDs, and none had peri-operative epilepsy (P=.001). Post-operative epilepsy control was not influenced by prophylactic AEDs (P=.226). Gross total resection (GTR) of tumors was associated with shorter SFS than subtotal resection (hazard ratio = 5.62; P = .045).
Conclusions: Convexity and parasagittal area tumors as well as peritumor edema strongly induce epilepsy. Pre-operative epilepsy predicts epilepsy after surgery. Malignant meningiomas contributed to poorer seizure control than atypical lesions. AEDs improve SFS, and prophylactic AEDs eliminate peri-operative epilepsy. Radical excision correlates with a higher seizure rate.
Patient Care: Atypical and malignant meningiomas are rare, comparing to benign subtypes.
My research can improve patient care
1. Provide predictive factors for seizure occurrence and prognostic factors of seizure control after surgical resection to these two types of meningiomas
2. Advice for prophylatic AED in seizure prevention for patients with atypical and malignant meningiomas
Learning Objectives: By the conclusion of this session, participants should be able to:
1. Describe the importance of seizure in patients with atypical and malignant meningiomas
2. Identify the factors of seizure occurrence and outcome in atypical and malignant meningiomas
3. Discuss about effective treatment with AEDs for seizure control in these patient group.