AIM: To evaluate the long-term clinical outcomes and histopathological classifications of anterior temporal lobectomy in adult patients with mesial temporal lobe epilepsy (TLE) associated with hippocampal sclerosis.

MATERIAL and METHODS: This was a retrospective study of 168 adult patients diagnosed with drug-resistant mesial temporal lobe epilepsy who underwent resection surgery and were histopathologically confirmed to have hippocampal sclerosis between 2006 and 2025. Preoperative evaluations included video-EEG, high-resolution brain Magnetic Resonance Imaging, neuropsychological tests, and PET-CT. Postoperative outcomes were assessed using the Engel classification. The impact of demographic characteristics, age at epilepsy onset, epilepsy duration, initial precipitating injury, family history, histopathological findings, and diagnostic evaluations on long-term seizure outcomes was evaluated using Kaplan-Meier and multivariate analyses.

RESULTS: Among the 168 patients included in the study, 95.2% achieved Engel Class I seizure freedom in the first year, with a long-term seizure freedom rate of 85.1%. The mean follow-up duration was 117.74 months. Histopathological evaluations revealed that HS-ILAE Type 1 was the most common histopathological classification, (73.8%). Longer preoperative epilepsy duration (p=0.009) and positive family history were risk factors for seizure recurrence (p=0.021). There was no significant association between histopathological classification and seizure control (p>0.05).

CONCLUSION: Anterior temporal lobectomy are effective surgical options for achieving high rates of seizure freedom in patients with mesial TLE associated with hippocampal sclerosis. Longer preoperative epilepsy duration and a positive family history were identified as negative prognostic factors for seizure recurrence. This study makes a significant contribution to the literature, with long-term outcomes of these procedures in a large cohort of adult patients with TLE.