SEIZURE CONTROL FOLLOWING TUMOR SURGERY FOR CHILDHOOD CORTICAL LOW-GRADE GLIOMAS

Detailed preoperative electroencephalographic (EEG) studies are now re commended for children with seizures and cortical tumors to define sei zure foci prior to surgery. To develop a historical perspective for be tter evaluation of results from series reporting tumor removal combine d with resection of seizure foci, the authors reviewed seizure outcome in 60 children with seizures and low-grade neoplasms treated consecut ively since 1981 by surgical resection without concomitant EEG monitor ing or electrocortical mapping. Forty-seven of the 60 tumors were tota lly or near-totally resected; 45 patients were seizure-free and two we re significantly improved 1 year following surgery. Of the 50 children in this series with more than five seizures prior to surgery, 36 were seizure-free, two were significantly improved, and 12 were not improv ed. Factors associated with poor seizure control included a parietal t umor location, a partial tumor resection, and a history of seizures fo r more than 1 year prior to surgery. The children at highest risk for poor seizure control at 2 years had experienced seizures for more than 1 year prior to surgery and had undergone partial resection of their parietal low-grade glial tumors or gangliogliomas. In contradistinctio n, the best seizure control was seen in patients with totally resected low-grade gliomas or gangliogliomas who had experienced seizures for less than 1 year (concordance rates for being seizure-free ranged from 78% to 86%). Long-term seizure control remained excellent. These resu lts suggest that seizure control can be obtained 2 years following tum or surgery in the majority of children with presumed tumors after exte nsive tumor resection without concomitant EEG monitoring or electrocor tical mapping.