Seizures in children with dysembryoplastic neuroepithelial tumors of the brain—A review of surgical outcomes across several studies

Abstract

PurposeIn children and adolescents, dysembryoplastic neuroepithelial tumors (DNETs) of the brain present with seizures almost 100 % of the time, potentially creating significant long-term morbidity and disability despite the generally indolent course of the lesion. These tumors also tend to be quite resistant to anti-epileptic drugs which, themselves, can be associated with long-term side effects and resultant disability. Many clinicians advocate early surgical resection of these lesions, but how effective this approach is, and how aggressive tumor removal should be, continues to be debated.MethodsWe performed a systematic review of the relevant literature to identify all reports of DNET resections in pediatric patients published over the past 20 years. In all, over 3000 MEDLINE abstracts were reviewed, ultimately resulting in 13 studies with 185 pediatric DNET patients to review.ResultsSurgical resection of the lesion was effective at improving seizures in over 98 % of patients and at achieving long-term seizure freedom in 86 %. Surgical resection of DNETs also appeared to be quite safe, with no reported perioperative deaths and an overall rate of postoperative complications of 12 %; the vast majority of these complications were transient.ConclusionsTotal gross resection of the lesion was the only factor statistically correlated with long-term seizure freedom (r = 0.63, p = 0.03). However, data remain lacking regarding whether this translates into more extensive procedures—like brain mapping and partial lobectomies—being any more effective than simple lesionectomies alone. Further research is clearly needed to address this and other crucial questions.

Association of different uncus lesions on magnetic resonance imaging with epilepsy

“…Medial temporal lobe is a site of predilection for DNET, mesial temporal sclerosis and herpes encephalitis which are known to be highly associated with epilepsy 15,16 . The great majority of these patients (15 of 18 patients) in the current study are shown to experience epilepsy/seizures.…”

Factors associated with seizure and cognitive outcomes after epilepsy surgery for low-grade epilepsy-associated neuroepithelial tumors in children

“…7,40) Therefore, the etiology of tumor-induced seizures is multifactorial and extends beyond the physical size of the tumor itself. 41,42) Factors associated with seizure outcomes after epilepsy surgery for LEATs…”

“…Several studies that included large numbers of patients confirmed that gross total resection is among the strongest factors leading to seizure freedom after LEAT resection. 41,[56][57][58] However, some studies have stated otherwise. 49,50,59,60) Gross total resection may not be possible if the tumor is located adjacent to eloquent areas or other functional cortical areas.…”

Surgical strategies for pediatric epilepsy

“…The most robust predictor of complete seizure freedom across available studies has been the extent of tumor resection (61,64 (65,66). The high rate of seizure freedom after surgery in patients with neoplasm-related epilepsy is especially meaningful given the long expected survival in children harboring low-grade brain tumors (67).…”