Resection of a dysembryoplastic neuroepithelial tumor in the precentral gyrus.

Background: Dysembryoplastic neuroepithelial tumors (DNTs) are common causes of intractable epilepsy in pediatric epilepsy patients. The effect of surgical intervention is often limited when the tumor is located in the precentral gyrus. Furthermore, complete surgical resection is often not performed in order to avoid permanent neurological deficits.

Methods: Here, we present a pediatric patient with intractable epilepsy caused by a simple DNT located in the precentral gyrus. Intracranial electrodes were implanted and used in combination with magnetic resonance imaging, video-electroencephalography and electrical cortical stimulation to assess neurological function, and where the epileptogenic zone was located.

Results: The results of intracranial electrode monitoring suggested that the epileptogenic zone was located in the tumor area and that cortical function had been reorganized. We completely resected the tumor based on these findings. The patient has been seizure free after the surgery and has not had any neurological deficits.

Conclusions: Simple form DNTs in the precentral gyrus can be completely resected with careful preoperative assessment of cortical function. Cortical reorganization could partly explain the functional preservation after surgery.