Abstracts

The management of seizures in brain tumor patients may be complicated by anti-epileptic drug (AED) interactions with anti-neoplastic agents, anti-emetics, antibiotics, analgesics, and other medications. Management may be further complicated by adverse effects of AEDs like bone marrow suppression, hyponatremia, and rash. Recent studies suggest that LEV carries less risk of inducing such complications, and investigation of its use in this population is warranted. Our objective was to assess the efficacy and tolerability of levetiracetam (LEV) in patients with brain tumors and seizures. This is a retrospective study of 15 patients (ages 24 to 76 years, mean age 48) evaluated between 1-1-03 and 12-1-03. All patients had either primary or metastatic intracranial tumors involving the frontal, temporal, or parietal lobes. All patients had at least one seizure of simple partial, complex partial, or generalized convulsive type. Mean duration on LEV was 7.25 months (range: 3 weeks to 26 months). Mean dose was 1016 mg/day (range: 500 to 2000 mg/day). LEV was monotherapy in 6 patients (40%). Nine patients (60%) were on 1-3 concomitant AEDs. LEV was first-line therapy in three of the fifteen patients. All patients had a minimum of three months follow-up. Of six patients on LEV monotherapy, all were seizure free. Two of nine patients on LEV adjuvant therapy had improved seizure control. Of three patients on first-line LEV therapy, two became seizure free. Seven (47%) patients, over all, had no definite change in seizure control while on LEV.
Two of the fifteen (13%) patients required discontinuation of LEV, and one required decreased dosage. These changes were the result of behavioral adverse effects rather than efficacy. Other adverse effects were dizziness and fatigue (7%), lethargy (7%), and insomnia (7%). No abnormal blood counts, infections, rashes, or metabolic abnormalities were associated with LEV. Three patients underwent adjuvant radiotherapy for their tumors, but no dermatitis was reported. LEV is an attractive AED for brain tumor patients because of its favorable pharmacokinetic profile and minimal impact on cell counts and blood chemistries. In these fifteen patients, LEV appeared to have efficacy and tolerability comparable to that seen in non-tumor patients with epilepsy. LEV monotherapy may show potential in this challenging patient population.
Future work involving larger patient numbers may allow for both statistical confirmation of these findings and more detailed evaluation of efficacy and tolerability based on tumor type and location.