Prophylactic Antiepileptic Drugs in Patients with Brain Tumors

Abstract

Seizure Prophylaxis in Patients with Brain Tumors: A Meta-analysis Sirven JI, Wingerchuk DM, Drazkowski JF, Lyons MK, Zimmerman RS Mayo Clin Proc 2004;79:1489–1494 Purpose To assess whether antiepileptic drugs (AEDs) should be prescribed to patients with brain tumors who have no history of seizures. Methods We performed a meta-analysis of randomized controlled trials (1966 to 2004) that evaluated the efficacy of AED prophylaxis versus no treatment or placebo to prevent seizures in patients with brain tumors who had no history of epilepsy. Summary odds ratios were calculated by using a random-effects model. Three subanalyses were performed to assess pooled odds ratios (ORs) of seizures in patients with primary glial tumors, cerebral metastases, and meningiomas. Results Of 474 articles found in the initial search, 17 were identified as primary studies. Five trials met inclusion criteria: patients with a neoplasm (primary glial tumors, cerebral metastases, and meningiomas) but no history of epilepsy who were randomized to either an AED or placebo. The three AEDs studied were phenobarbital, phenytoin, and valproic acid. Of the five trials, four showed no statistical benefit of seizure prophylaxis with an AED. Meta-analysis confirmed the lack of AED benefit at 1 week (OR, 0.91; 95% confidence interval [CI], 0.45–1.83) and at 6 months (OR, 1.01; 95% CI, 0.51–1.98) of follow-up. The AEDs had no effect on seizure prevention for specific tumor pathology, including primary glial tumors (OR, 3.46; 95% CI, 0.32–37.47), cerebral metastases (OR, 2.50; 95% CI, 0.25–24.72), and meningiomas (OR, 0.62; 95% CI, 0.10–3.85). Conclusions No evidence supports AED prophylaxis with phenobarbital, phenytoin, or valproic acid in patients with brain tumors and no history of seizures, regardless of neoplastic type. Subspecialists who treat patients with brain tumors need more education on this issue. Future randomized controlled trials should address whether any of the newer AEDs are useful for seizure prophylaxis.