Symptomatic epilepsy is frequently encountered in patients with brain metastases (BM), affecting up to 25% of them. However, it generally remains unknown whether the risk of seizures in such cases is affected by stereotactic radiosurgery (SRS), which involves highly conformal delivery of high-dose irradiation to the tumor with a minimal effect on adjacent brain tissue. Thus, the role of prophylactic administration of antiepileptic drugs (AED) after SRS remains controversial. A comprehensive review and analysis of the available literature reveals that according to prospective studies, the incidence of seizures after SRS for BM varies from 8% to 22%, and there is no evidence that SRS increases the incidence of symptomatic epilepsy. Therefore, routine prophylactic administration of AED prior to, during, or after SRS in the absence of a seizure history is not recommended. Nevertheless, short-course administration of an AED may be judiciously considered (on the basis of class III evidence) for selected high-risk individuals.
Keywords: Antiepileptic drugs; Fractionated radiotherapy; Intracranial metastases; Prophylactic antiepileptic therapy; Seizures; Stereotactic radiosurgery; Symptomatic epilepsy.