From location to manifestation: a systematic review and meta-analysis of seizure prevalence in different brain tumor sites

Objectives: The location of the brain tumor in the frontal or temporal lobes has been reported as a predictor for seizure occurrence in patients with a brain tumor but the predictive value of other locations is uncertain. We aimed to ascertain the pooled prevalence of pre-operative seizures in relation to the brain tumor locations, by employing a systematic review and meta-analysis. Methods: The search was conducted up to 1st May 2023, in Pubmed, Embase, and Web of Science and references were exported and managed using EndNote 20. Articles were included if they reported a prevalence or incidence of the seizure at the tumor location. MetaXL by Epigear was used to generate the meta-analysis. Results: The pooled prevalence for preoperative seizures in gliomas was 51–63% in most locations (frontal, temporal, parietal, and insula) but lowest in the occipital lobe (28%). Subgroup analysis on low-grade gliomas showed a high pre-operative seizure prevalence in all locations: frontal lobe [75% (95% CI: 68–81%)], temporal lobe [73% (95% CI: 63–82%)], parietal lobe [79% (95% CI: 57–82%)], occipital lobe [46% (95% CI: 0–95%)], and insular [76% (95% CI: 65–77%)]. In the astrocytoma and meningioma subanalysis, the pooled prevalence is ≥ 40% in most cortical location. In brain metastases, the pooled prevalence was similar in most locations (18–39%), lowest in the temporal lobe. Conclusion: Tumor location is not the main influencing factor for pre-operative seizure independent from tumor type. Extensive seizure screening should be considered irrespective of tumor location, especially in those with low-grade gliomas.