Glioneuronal tumors and epilepsy in children: seizure outcome related to lesionectomy

Aim. Glioneuronal tumors (especially gangliogliomas and dysembryoplastic neuroepithelial tumors) are an increasingly recognised cause of drug-resistant epilepsy in children. The optimal surgical strategy (lesionectomy vs. extended resection of epileptogenic peritumoral areas) to obtain seizure control has not been fully established. Our aim was to analyze the post-surgical seizure outcome in children with epileptogenic glioneuronal tumors related to lesionectomy. Methods. The clinical data were collected through a database. Video-EEG and MRI were performed in all patients pre-operatively and at the follow-up. Results. Our series included 22 patients. The age range at surgery was 10 months-16 years (mean: 6.5±4.5 years). Epilepsy duration ranged 1-78 months (mean: 11.6±17.0). There were complex partial seizures in 14 cases, simple partial seizures in 6 patients and generalized epilepsy in 2. Gross-total surgical removal was achieved in 15 (68.2%) patients. At the last follow-up (mean 4.7 years), 20 (90.9%) patients were seizure-free (Engel Class I) and two (9.1%) were Engel Class III. Six out of seven (85.7%) patients with subtotal removal were Engel Class I. Statistical analysis failed to detect any difference between seizure outcome (Engel Class) and tumor type (DNT vs. GG; P=1.00) or location (temporal vs. non temporal; P=0.51), and extension of the resection (total vs. subtotal; P=1.00). Conclusion. Primary aim of the surgery for epileptogenic glioneuronal tumors is to remove the lesion and to obtain a complete seizure control. However, if a complete tumor resection cannot be carried out, a subtotal removal of the lesion can equally provide satisfactory results.