Seizure outcomes in patients with brain metastases and epilepsy: a systematic review on the efficacy of antitumor treatment and antiseizure medication.

Background: Epilepsy is a common symptom in patients with brain metastases (BMs), and because of the rising incidence of BMs, adequate seizure management is warranted. We conducted a systematic review on seizure outcomes after antitumor treatment and antiseizure medication (ASM) in patients with BMs from solid tumors and epilepsy.

Methods: A literature search was performed in 6 databases up to February 2024. Extracted outcomes were rates for (1) seizure freedom, (2) ≥50% seizure reduction, and (3) treatment failure (for ASM only). Weighted averages (WAs) were calculated for outcomes after surgery at 6 months follow-up. Quality assessment of the included studies was performed using the Risk Of Bias In Non-randomized Studies of Interventions (ROBINS-I) tool.

Results: We retrieved 2244 references, of which 16 studies were eligible for inclusion. Eight studies were at critical, and 8 studies at serious risk of bias. The WA of seizure freedom rates at 6 months after surgical resection was 64% (based on 3 studies at serious risk of bias, n = 151 patients). Results on ASM efficacy and tolerability were unreliable, as all eligible studies for these outcomes were at critical risk of bias.

Conclusions: Limited available evidence from heterogeneous study populations demonstrated that in the majority of patients with epilepsy due to BMs, seizure freedom 6 months after surgical resection may be reached. No substantial evidence on ASM efficacy and tolerability in patients with epilepsy due to BMs is available. High-quality cohort studies are warranted to expand the evidence on seizure outcomes after antitumor and ASM treatment.