Epilepsy surgery in genetic epilepsies: the pathway predicts seizure freedom better than the lesion

Design

Systematic review with individual-participant pooled analysis

Population

272 people with germline genetic epilepsy undergoing resection or laser ablation

Primary outcome

Seizure freedom (Engel I) at last follow-up

Effect

Vascular 73.6%, GATORopathies 65.8%, channelopathies 30.0%, synaptopathies 22.2%

This pooled individual-patient analysis combined 224 published cases with 48 from institutional and paediatric consortium databases: 272 people with pathogenic germline variants, excluding tuberous sclerosis, who had resection or laser ablation. Median follow-up was 24 months.

Seizure freedom was achieved in 74% of vascular disorders, 66% of GATOR-pathway (mTOR-related) disorders and 58% of copy-number variants, but only 30% of channelopathies and 22% of synaptopathies. The low rates in channelopathies and synaptopathies held even when MRI showed a lesion, which most did.

In practice, a genetic diagnosis should not exclude surgery, and in GATOR-pathway epilepsy it may strengthen the case. In channelopathies and synaptopathies, a visible lesion is weaker reassurance than usual, and expectations need setting accordingly. The data are retrospective and drawn mostly from published reports, which favour successes.

• Do not exclude a patient from surgical evaluation because of a germline genetic diagnosis.
• Expect better surgical outcomes in GATOR-pathway and vascular genetic epilepsies.
• Set lower expectations in channelopathies and synaptopathies, even with an MRI lesion.
• Include genetic results in the epilepsy surgery multidisciplinary discussion.

Why it matters

It turns a genetic result from a reason to avoid surgery into a guide to who benefits.

Don't overread it

Largely retrospective and literature-based; publication bias likely inflates success rates.

The statistics, in plain English

Odds ratios of 0.22 and 0.23 for channelopathies and synaptopathies mean roughly four-fold lower odds of seizure freedom than other groups. Some groups are small (19 vascular cases), so their estimates are imprecise. Published case reports tend to over-represent good outcomes.

Read the rest in the app

You have read your two free briefings this month. The app carries all 27 specialties, every morning, free — and this finding is waiting in it.

Get Daily Doctor — free

Scan to keep reading on your phone. No account needed to start.