Temporal lobe tumoral epilepsy - Characteristics and predictors of surgical outcome

Objective: To review the clinical and neurophysiologic features and surgical outcome in patients with intractable temporal lobe tumoral epilepsy. Methods: Patients with intractable temporal lobe epilepsy who underwent resection of temporal lobe tumors, confirmed by surgical pathology, seen between 1985 and 2000 at Yale University School of Medicine Epilepsy Center, were selected. Medical records were reviewed for age at diagnosis, age at onset of seizures, delay between seizure onset and tumor diagnosis, types and frequencies of seizures, EEG results, use of anticonvulsants, extent of surgery, and pathologic diagnosis. Results: Sixty-eight patients were identified, 94.1% of them with low-grade tumors. Complex partial seizure was the most common seizure type. All patients underwent at least one surgical procedure with average follow-up of 9 years after surgical intervention. Eighty-seven percent of patients had significant postoperative seizure improvement (Engel's classes I and II). Gross total tumor resection predicted postoperative seizure freedom (p=0.002), whereas patients with early surgical intervention, auras, and simple partial seizures had a tendency toward better seizure outcome. Conclusions: Long-term follow-up of patients with intractable temporal lobe tumoral epilepsy suggests good response of seizures to surgery, which is unrelated to age at diagnosis, EEG, or pathology. Extent of tumor resection was significantly predictive of outcome, whereas early intervention and presence of simple partial seizures showed trends as predictive factors.