Surgical management of epilepsy associated with temporal lobe tumors

Object: Despite advancement in neuroimaging and improvement in the knowledge of tumor behavior, the optimal surgical treatment of patients with temporal-lobe tumors remains unclear. Controversies still exist regarding the type of tumor surgery, i.e., lesionectomy alone or in combination with resection of mesial temporal structures and epileptogenic cortex adjacent to the tumor and the extent of tumor removal. In this retrospective study, the authors have analyzed seizure outcome in a series of children with epileptogenic temporal lobe tumors who had been treated only by lesionectomy. Materials and Methods: Sixteen patients including 7 boys and 9 girls, with a mean age of 9.9 years (range: 5-17 years) underwent lesionectomy as the only surgical treatment for temporal lobe tumor related epilepsy. The interval between onset of seizures and surgery ranged from 3 months to 7.5 year (mean 5.9 year). Ten patients (62.5%) presented with complex partial seizures and the remaining 6 (37.5%) had simple partial seizures with secondary generalization, with seizure frequency varying from several per day to only a few per month. All tumors were located within the temporal lobes: 8 temporomesial, 5 temporolateral and 3 temporobasal. Cortical dysplasia adjacent to tumor, hippocampal sclerosis or tumor infiltration was not demonstrated in any patient. Results: Gross total resection of the tumor was achieved in 11 (69%) and subtotal resection in 5 (31%) patients. The histopathological diagnosis was ganglioglioma in 6 (37.5%) patients, dysembryoplastic neuroepithelial tumor in 5 (31.3%), low-grade astrocytoma in 2 (12.5%), juvenile pilocytic astrocytoma in 2 (12.5%) and pleomorphic xanthoastrocytoma in 1 (6.3%). At a mean follow-up of 5.2 years (range, 1.4-9.3 years), 11 (69%) patients were seizure-free (Engel class I) and 4 (25%) others had a significant improvement in the seizure frequency (Engel class II). Conclusions: The results of this study suggest that good long-term seizure control can be achieved with lesionectomy alone in majority of children suffering from medically resistant epilepsy associated with temporal lobe tumors.