Epilepsy outcome following resection of low-grade brain tumors in children

Abstract

<jats:sec><jats:title>OBJECTIVE</jats:title><jats:p>The indication for and timing of surgery for epilepsy associated with low-grade mixed neuronal-glial tumors may be controversial. The purpose of this study was to evaluate the effect of resection and associated variables on epilepsy and on progression-free survival (PFS).</jats:p></jats:sec><jats:sec><jats:title>METHODS</jats:title><jats:p>A retrospective chart review of patients treated between 1992 and 2016 was conducted to identify individuals with epilepsy and low-grade gliomas or neuronal-glial tumors who underwent resective surgery. Data analyzed included age at epilepsy onset, age at surgery, extent of resection, use of electrocorticography, the number of antiepileptic drugs (AEDs) before and after surgery, the presence of dysplasia, Engel class, histological findings, and PFS. The institutional review board protocol was specifically approved to conduct this study.</jats:p></jats:sec><jats:sec><jats:title>RESULTS</jats:title><jats:p>A total of 107 patients were identified. The median follow-up was 4.9 years. The most common pathology was dysembryoplastic neuroepithelial tumor (36.4%), followed by ganglioglioma (31.8%). Eighty-four percent of patients had Engel class I outcomes following surgery. Gross-total resection was associated with a higher likelihood of an Engel class I outcome (90%) as compared to subtotal resection (58%) (p = 0.0005). Surgery reduced the AED burden, with 40% of patients requiring no AEDs after surgery (p &lt; 0.0001). Children with neurodevelopmental comorbidities (n = 5) uniformly did not experience seizure improvement following resection (0% vs 83% overall; p &lt; 0.0001). Electrocorticography was used in 33% of cases and did not significantly increase class I outcomes. PFS was 90% at 5 years. Eleven percent of tumors recurred, with subtotal resection more likely to result in recurrence (hazard ratio 5.3, p = 0.02). Histological subtype showed no significant impact on recurrence.</jats:p></jats:sec><jats:sec><jats:title>CONCLUSIONS</jats:title><jats:p>Gross-total resection was strongly associated with Engel class I outcome and longer PFS. Further studies are needed to elucidate the suitable time for surgery and to identify factors associated with oncological transformation.</jats:p></jats:sec>

Seizures following surgery for supratentorial extratemporal low-grade tumors in children: a multicenter retrospective study

“…For example, the most common causes of tumor-related epilepsy are glioneuronal tumors, accounting for approximately 40% of all tumors causing epileptic seizures. 8,9 While in adults the most common form of epilepsy is temporal lobe epilepsy, in children the majority of cases are extratemporal epilepsy. 10 Extratemporal epilepsy is characterized by a younger age at seizure onset than that of temporal epilepsy.…”

“…14 Several publications have described the outcomes of epilepsy associated with temporal lobe LGG, leading to an 80%-100% seizurefree rate following tumor resection. 8,15,16 Literature focusing on the occurrence of postoperative seizures following the resection of supratentorial extratemporal (STET) LGG in children (with or without a seizure history), and the impact of preoperative seizures or epilepsy on postoperative epilepsy risk is scarce. 8,9 Several studies in children include temporal as well as STET lesions.…”

“…8,15,16 Literature focusing on the occurrence of postoperative seizures following the resection of supratentorial extratemporal (STET) LGG in children (with or without a seizure history), and the impact of preoperative seizures or epilepsy on postoperative epilepsy risk is scarce. 8,9 Several studies in children include temporal as well as STET lesions. 8,9,17,18 Other studies in children include only patients with preoperative refractory epilepsy (including other pathologies besides LGGs).…”

“…8,9 Several studies in children include temporal as well as STET lesions. 8,9,17,18 Other studies in children include only patients with preoperative refractory epilepsy (including other pathologies besides LGGs). 13,19 Many studies combine pediatric and adult patients with STET LGGs.…”

Beyond the neuro-oncological outcome: A perspective of the seizure control after resection of the medial temporal lobe gliomas

“…On the other hand, the epileptologic outcome (seizure-freedom), one of the final targets in patients with lesional temporal lobe epilepsy (TLE), has also been suggested to be dependent on the complete epileptogenic zone resection. [ 1 ] However, these two different aspects of the clinical outcome do not always move parallel to each other: some patients with partial resection of the tumor experience significant seizure control, while some others with apparently gross total resection of the tumor have a suboptimal epileptologic outcome. [ 2 ] This discrepancy originates from shortages of our knowledge about the exact predicting factors of the best seizure outcome after lesionectomy in each patient.…”