Seizure outcome of surgical treatment of focal epilepsy associated with low-grade tumors in children

Abstract

<jats:sec> <jats:title>Object</jats:title> <jats:p>Low-grade tumor (LGT) is an increasingly recognized cause of focal epilepsies, particularly in children and young adults, and is frequently associated with cortical dysplasia. The optimal surgical treatment of epileptogenic LGTs in pediatric patients has not been fully established.</jats:p></jats:sec> <jats:sec> <jats:title>Methods</jats:title> <jats:p>In the present study, the authors retrospectively reviewed 30 patients (age range 3–18 years) who underwent surgery for histopathologically confirmed LGTs, in which seizures were the only clinical manifestation. The patients were divided into 2 groups according to the type of surgical treatment: patients in Group A (20 cases) underwent only tumor removal (lesionectomy), whereas patients in Group B (11 cases) underwent removal of the tumor and the adjacent epileptogenic zone (tailored surgery). One of the patients, who underwent 2 operations, is included in both groups. Follow-up ranged from 1 to 17 years.</jats:p></jats:sec> <jats:sec> <jats:title>Results</jats:title> <jats:p>Sixteen (80%) of 20 patients in Group A had an Engel Class I outcome. In this group, 3 of 4 patients who were in Engel Classes II and III had temporomesial lesions. All patients in Group B had temporomesial tumors and were seizure free (Engel Class I). In this series, in temporolateral and extratemporal tumor locations, lesionectomy yielded a good seizure outcome. In addition, a young age at seizure onset (in particular &lt; 4 years) was associated with a poor seizure outcome.</jats:p></jats:sec> <jats:sec> <jats:title>Conclusions</jats:title> <jats:p>Tailored resection in temporomesial LGTs was associated with excellent seizure outcome, indicating that an adequate presurgical evaluation including extensive neurophysiological evaluation (long-term videoelectroencephalography monitoring) to plan appropriate surgical strategy is advised.</jats:p></jats:sec>

Seizure outcome in surgically treated drug-resistant mesial temporal lobe epilepsy based on the recent histopathological classifications

“…44 We confirmed these results in a recent retrospective pediatric series. 4 The higher effectiveness of an extended resection, beyond the low-grade tumor, might depend on the frequent association of this tumor type with other epileptogenic pathologies, such as the spectrum of cortical dysplasias that might represent the origin of a widespread epileptic network. 2 The analysis of outcome in the different types of ELGT found in our patients is significantly limited by the small number of cases in each histopathological subtype; represented mainly by glioneuronal tumors, is currently enlarging not only for the recognition of new, often rare, histotypes but also for the continuous identification of tumors having hybrid or mixed features that suggest the existence of a histological spectrum that can be difficult to categorize.…”

Seizure control after subtotal lesional resection

“…Rep resentative results are summarized in Table 1. Many large studies of low-grade gliomas have been accumulated; 5,6,9,26,37,38 only 1 has specifically focused on high-grade glioma. 7 Glioneuronal tumors, specifically ganglioglioma and DNET, are often considered together 3,18 because of their overlapping clinical and pathological characteristics, including epileptogenicity.…”

Seizures in Children with Brain Tumours — Epidemiology, Significance, Management, and Outcomes

“…But how successful is tumour resection in terms of controlling or eliminating seizures? [214][215][216][217][218][219][220][221][222][223] published over the past two decades in which seizure outcomes in children and adolescents undergoing surgery to remove epileptogenic brain neoplasms were examined. Across these 26 studies are 741 patients, ranging in age from one month to 21 years of age, with a mean age of 9.1 years and a mean duration of post-operative follow-up of more than four years (overall mean=52 months, with individual study means ranging from 12 to 148 months).…”

“…Over the years, attempts have been made to optimize the resection of epileptogenic lesions by both better delineating their margins and identifying extra-tumoral epileptogenic tissue, using intra-operative tools like electrocorticography (ECoG) to identify potential seizure-inducing tissue irregularities like cortical dysplasia [63,77,93,132,1 [6] 3 , 184,214,216,240,241]. This has led to debate regarding the relative benefits and safety of performing epilepsy surgery rather than just lesionectomies in patients with tumour-triggered seizures [242]; though, in fact, many surgeons have been utilizing additional surgical steps like lobectomies, amygdylohypocampectomies and, in extreme cases, hemispherectomies for decades [63,86,94,117,132,148,149,168,182,185,214,217,218,222,227,243]. To date, almost no direct empirical comparisons have been undertaken.…”

“…Among thalamic tumours, for example, up to one third of paediatric patients present with seizures [38]. As such, and because even low-grade gliomas can nonetheless be infiltrative into high-function brain tissue [19,[48][49][50], while some of these lesions are totally resectable, others are not [51][52][53][54]. This creates dilemmas as to how aggressive to be, and therefore how much risk to take in their resection [55].…”