Tumor-associated epilepsy at diagnosis in glioblastoma patients reveals an inflammatory molecular signature and is associated with better overall survival

Lay Summary Glioblastoma patients who present with seizures at diagnosis live significantly longer than patients without seizures. In this multicenter study of more than 1100 patients, we show that tumor-associated epilepsy identifies a biologically distinct glioblastoma subtype characterized by inflammatory and immune-related features. Seizure status also influenced the effect of surgery: complete tumor removal was particularly important in patients with seizures. These findings suggest that seizures are not merely a symptom of glioblastoma, but a clinically relevant biomarker that may help guide prognosis, surgical decision-making, and future personalized therapies.