Epilepsy in patients with brain tumours: epidemiology, mechanisms, and management

Dose-dependent seizure control with MEK inhibitor therapy for progressive glioma in a child with neurofibromatosis type 1

BACKGROUND

Low-grade gliomas (LGGs) occurring in children can result in many different neurologic complications, including seizures. MEK inhibitors are increasingly being used to treat LGG, but their effect on associated neurologic symptoms has not been established.

RESULTS

Here, we report a patient with neurofibromatosis type 1 (NF1), medically refractory epilepsy (MRE), and an extensive optic pathway glioma (OPG) who developed dose-dependent seizure control while being treated with selumetinib. Seizure frequency rebounded after dose reduction for cardiac toxicity, then improved, and finally ceased after restarting full dosing, allowing confidence in the cause of improvement.

CONCLUSION

Selumetinib may have promise in epilepsy management in other children with NF1 or LGG.

The utility of intraoperative ECoG in tumor-related epilepsy: Systematic review

OBJECT

Epilepsy is one of the most common clinical manifestations of primary brain tumors. Intraoperative electrocorticography (ECoG) has been widely used in tumor resection. We aim to describe the indication and utility of ECoG during brain tumor surgery.

METHODS

We performed a systematic review of the literature on the prognosis of tumor-related epilepsy surgery guided by intraoperative ECoG. The published studies were searched in PubMed, Embase, and Web of Science using the keyword 'seizure' or 'epilepsy' and 'electrocorticography' or 'ECoG'. Two reviewer authors screened studies and extracted data independently.

RESULTS

Thirteen studies included 569 patients were finally selected, of which eight investigated medically intractable epilepsy. Three publications described temporal tumor-related epilepsy. All included studies were retrospective, and the age of all patients ranged from 1 to 71 years. The duration of epilepsy ranged from 1 month to 30 years. Patients with tumor-related epilepsy underwent surgical treatment with Engel I outcomes ranging from 56.5%-100%.

CONCLUSION

Intraoperative ECoG is generally considered a useful technique in delineating epileptogenic areas and improving the prognosis of surgical treatment of tumor-related epilepsy. However, large-scale randomized control trials are still needed to verify these findings and formulate appropriate surgical strategies.

Antiepileptic drug management in pediatric patients with brain tumor-related epilepsy

BACKGROUND

Patients with brain tumor-related epilepsy (BTRE) are at a higher risk of significant morbidity, lower quality of life, and increased risk of mortality. We surveyed providers regarding anti-seizure medication (ASM) management in pediatric BTRE to determine if practices are standard or markedly variable.

METHODS

An anonymous voluntary online survey was sent to members of the Child Neurology Society. Providers were asked specific questions regarding initiation and wean of ASMs and if this was dependent on multiple factors. Demographic information was collected.

RESULTS

Fifty-one providers responded to the survey. Ninety-four percent of providers would start an ASM after a second seizure. Eighty-four percent chose levetiracetam as the preferred ASM. Management was variable when based on tumor location, extent of surgical resection, pathology, and tumor prognosis. Statistically significant differences in responses regarding management were identified when comparing neurologists and epileptologists, providers with formal neuro-oncology or epilepsy training, providers at large institutions, and years of experience. For patients who underwent a gross total resection of the tumor, neuro-oncology and epilepsy-trained providers were more likely to wean off ASMs (p < 0.049). Providers without formal training in neuro-oncology or epilepsy were more likely to get an EEG prior to making a decision about weaning off ASMs (p < 0.016).

CONCLUSION

These results suggest that ASM management in BTRE varies greatly according to sub-specialty and experience. Further studies and potential development of guidelines are needed to identify the most appropriate management of ASMs for BTRE.

Tissue 2-Hydroxyglutarate and Preoperative Seizures in Patients With Diffuse Gliomas

BACKGROUND AND OBJECTIVES

Mutant isocitrate dehydrogenase (IDH) 1/2 gene products gain a new ability to produce D-2-hydroxyglutarate (D2HG). IDH1/2 mutations are thought to be associated with seizures owing to the structural similarity between D2HG and glutamate. However, the effects of D2HG on seizures in clinical settings are not fully understood. We sought to investigate the relationship between tissue 2-hydroxyglutarate (2HG) concentration and preoperative seizures using clinical samples.

METHODS

We included 104 consecutive patients with diffuse glioma who underwent surgery from August 2008 to May 2016 and whose clinical presentation and IDH1/2 status were identified. The presence of preoperative seizures, tumor location, histopathologic diagnosis, IDH1/2 status, and 1p/19q codeletion were assessed from the patient charts. Tissue 2HG concentration was measured using liquid chromatography-tandem mass spectrometry. To evaluate 2HG distribution without artefactual tissue disruption, we applied matrix-assisted laser desorption/ionization high-resolution mass spectrometry imaging (MALDI-MSI) in 12 patients' surgically resected samples. We assessed the correlation of preoperative seizures with tissue 2HG concentration, IDH1/2 status, WHO grade, and 1p/19q codeletion.

RESULTS

Tissue 2HG concentration was higher in IDH1/2 mutant tumors (IDH-Mut, n = 42) than in IDH1/2 wild-type tumors (IDH-WT, n = 62) (median 4,860 ng/mg vs 75 ng/mg) (p < 0.0001). MALDI-MSI could detect 2HG signals in IDH-Mut, but not in IDH-WT. Preoperative seizures were observed in 64.3% of patients with IDH-Mut and 21.0% patients with IDH-WT (p < 0.0001). The optimal cutoff value of tissue 2HG concentration for predicting preoperative seizures was 1,190 ng/mg, as calculated by the receiver operating characteristic curve. Increased preoperative seizure risk was only observed in tumors with 2HG concentration above the cutoff value among IDH-Mut (IDH-Mut with above the cutoff value: 71.4% vs IDH-Mut with below the cutoff value: 28.6%; p = 0.031). Multivariate analysis, including IDH1/2 mutation status, tissue 2HG concentration, WHO grade, and 1p/19q codeletion, revealed that only increased tissue 2HG concentration was associated with preoperative seizures (odds ratio 5.86, 95% confidence interval 1.02-48.5; p = 0.048).

DISCUSSION

We showed that high tissue 2HG concentration was associated with preoperative seizures, suggesting that excess 2HG increases risk of preoperative seizures in IDH1/2 mutant tumors.

IDH Wild-type Glioblastoma Presenting with Seizure: Clinical Specificity, and Oncologic and Surgical Outcomes

BACKGROUND

 Glioblastoma (GBM) is the most common and aggressive primary brain neoplasia in adults. Seizure is a common manifestation in GBM. Up to 25 to 60% of patients with GBM have seizures. We aim to summarize all the relevant clinical, surgical, radiologic, and molecular features of a cohort of patients suffering from GBM-related epilepsy and measure the outcome, to understand the possible existence of a clinical/phenotypical specificity of this subgroup of patients.

METHODS

 We retrospectively analyzed a cohort of 177 patients affected by isocitrate dehydrogenase wild-type (IDH-WT) GBM; 49 patients presented seizure at onset (SaO) and 128 were seizure free (SF). We investigated the relationship between seizures and other prognostic factors of GBMs.

RESULTS

 A statistically significant association between the location of the lesions in the parietal lobe and seizures was observed. The left side was more commonly affected. Interestingly, there was a statistical relationship between tumors involving the subventricular zone (SVZ) and SaO patients. The tumors were also smaller on average at diagnosis, and generalized SaOs were associated with longer overall survival.

CONCLUSIONS

 The typical patient with IDH-WT GBM with SaO is a young (<55 year) male without a history of headache. The lesion is typically small to medium in size and located in the temporoparietal dominant lobe, with a high tendency to involve the SVZ.

Molecular Docking Simulation Studies Identifies Potential Natural Product Derived-Antiwolbachial Compounds as Filaricides against Onchocerciasis

Onchocerciasis is the leading cause of blindness and severe skin lesions which remain a major public health problem, especially in tropical areas. The widespread use of antibiotics and the long duration required for effective treatment continues to add to the increasing global menace of multi-resistant pathogens. Onchocerca volvulus harbors the endosymbiont bacteria Wolbachia, essential for the normal development of embryos, larvae and long-term survival of the adult worm, O. volvulus. We report here results of using structure-based drug design (SBDD) approach aimed at identifying potential novel Wolbachia inhibitors from natural products against the Wolbachia surface protein (WSP). The protein sequence of the WSP with UniProtKB identifier Q0RAI4 was used to model the three-dimensional (3D) structure via homology modelling techniques using three different structure-building algorithms implemented in Modeller, I-TASSER and Robetta. Out of the 15 generated models of WSP, one was selected as the most reasonable quality model which had 82, 15.5, 1.9 and 0.5% of the amino acid residues in the most favored regions, additionally allowed regions, generously allowed regions and disallowed regions, respectively, based on the Ramachandran plot. High throughput virtual screening was performed via Autodock Vina with a library comprising 42,883 natural products from African and Chinese databases, including 23 identified anti-Onchocerca inhibitors. The top six compounds comprising ZINC000095913861, ZINC000095486235, ZINC000035941652, NANPDB4566, acetylaleuritolic acid and rhemannic acid had binding energies of −12.7, −11.1, −11.0, −11, −10.3 and −9.5 kcal/mol, respectively. Molecular dynamics simulations including molecular mechanics Poisson-Boltzmann (MMPBSA) calculations reinforced the stability of the ligand-WSP complexes and plausible binding mechanisms. The residues Arg45, Tyr135, Tyr148 and Phe195 were predicted as potential novel critical residues required for ligand binding in pocket 1. Acetylaleuritolic acid and rhemannic acid (lantedene A) have previously been shown to possess anti-onchocercal activity. This warrants the need to evaluate the anti-WSP activity of the identified molecules. The study suggests the exploitation of compounds which target both pockets 1 and 2, by investigating their potential for effective depletion of Wolbachia. These compounds were predicted to possess reasonably good pharmacological profiles with insignificant toxicity and as drug-like. The compounds were computed to possess biological activity including antibacterial, antiparasitic, anthelmintic and anti-rickettsials. The six natural products are potential novel antiwolbachial agents with insignificant toxicities which can be explored further as filaricides for onchocerciasis.

Identification and Validation of a Seizure-Free-Related Gene Signature for Predicting Poor Prognosis in Lower-Grade Gliomas

Background

Lower-grade gliomas (LGGs) patients presented seizure-free have a worse survival than those presented with seizures. However, the current knowledge on its potential value in LGGs remains scarce.

Purpose

This study aimed to identify a novel gene signature associated with seizures-free for predicting poor prognosis for LGGs patients.

Materials and Methods

The RNA expression and clinical information of LGGs patients were downloaded from the Cancer Genome Atlas database. Differentially expressed genes (DEGs) were screened out between LGGs patients presented seizures-free and seizures. The novel gene signature was constructed by Lasso and multivariate regression analyses for predicting prognosis in LGGs. Its prognostic value was assessed and validated by Kaplan-Meier analyses and receiver operating characteristic (ROC) curves. Multivariate regression analysis was applied to identify the independent prognostic value of the gene signature. Furthermore, bioinformatics analysis was performed to elucidate the molecular mechanisms.

Results

A total of 253 DEGs were screened out between LGG patients presented with seizures and free of seizures. A 5-gene signature (HIST1H4F, HORMAD2, LILRA3, PRSS33, and TBX20 genes) was constructed from these 253 DEGs. Kaplan-Meier analyses and ROC curves assessed and validated the good performance of the 5-gene signature in differentiating and predicting prognosis of high- and low-risk patients. Multivariate regression analysis determined the independent prognostic value of the 5-gene signature. According to bioinformatics analysis, DEGs were mainly enriched in biological processes related to positive regulation of transcription from RNA polymerase II promoter, G-protein coupled receptor signaling pathway, and pathways of cytokine-cytokine receptor interaction, chemokine signaling pathway.

Conclusion

Our findings suggested that the 5-gene signature might serve as a potential prognostic biomarker and provide guidance for the personalized LGGs management.

Changes in epilepsy causes of death: A US population study

OBJECTIVES

Since 2000, medical treatment for epilepsy and cardiovascular risk-reduction strategies have advanced significantly in the United States (US). However, seizure-free rates remain unchanged, and people with epilepsy are at higher risk than the general population for heart disease and stroke. The purpose of this study is to determine how cardiovascular, epilepsy-related, and other causes of death are changing in epilepsy in comparison with the US population.

MATERIALS & METHODS

Changes in the 15 underlying causes of death in epilepsy (ICD-10 G40-G40.9) and the US population were analyzed and compared from 2000 to 2018. The CDC multiple cause-of-death database was utilized as the primary data source. Changes in the relative proportions for each cause-of-death over were evaluated using logistic regression.

RESULTS

The proportions of deaths in epilepsy due to heart disease declined 34.4% (p < .001), a rate similar to the general population (39.9%). Epilepsy-related deaths declined 25% as a percentage of all epilepsy deaths (p < .001). The proportions of deaths due to stroke and neoplasms increased significantly in epilepsy versus the US population (p < .001 linear trend).

CONCLUSIONS

The reduction in ischemic heart disease in epilepsy is a novel and highly significant finding, which reflects widespread implementation of cardiovascular risk-factor reduction and treatment in the United States. Reductions in epilepsy-related deaths are an exciting development which requires further investigation into causality. The increase in deaths due to neoplasms and stroke relative to the US population is concerning, warranting vigilance and increased efforts at recognition, prevention, and treatment.

Effect of Levetiracetam Use Duration on Overall Survival of Isocitrate Dehydrogenase Wildtype Glioblastoma in Adults: An Observational Study

OBJECTIVES

The association between Levetiracetam and survival of Isocitrate Dehydrogenase (IDH) wildtype glioblastomas is controversial. We investigated whether the duration of Levetiracetam use during the standard chemoradiation protocol impacts overall survival of IDH-wildtype glioblastoma patients.

METHODS

Observational single-institution cohort study (2010-2018). Inclusion criteria were: 1) patients ≥18 years old; 2) newly diagnosed supratentorial tumor; 3) histomolecular diagnosis of IDH-wildtype glioblastoma; 4) standard chemoradiation protocol. To assess the survival benefit of Levetiracetam use during the standard chemoradiation protocol (whole duration, part time, and never subgroups), a Cox proportional hazard model was constructed. We performed a case-matched analysis (1:1) between patients with Levetiracetam use during the whole duration of the standard chemoradiation protocol and patients with Levetiracetam use part time or never according to the following criteria: sex, age, epileptic seizures at diagnosis, RTOG-RPA class, tumor location, preoperative volume, extent of resection, and O6-Methylguanine-DNA methyltransferase promoter methylation status. Patients with unavailable O6-Methylguanine-DNA methyltransferase promoter methylation status (48.5%) were excluded.

RESULTS

460 patients were included. The median overall survival was longer in the 116 patients with Levetiracetam use during the whole duration of the standard chemoradiation protocol (21.0 months; 95%CI, 17.2-24.0) than in the 126 patients with part time Levetiracetam use (16.8 months; 95%CI, 12.4-19.0], and in the 218 patients who never received Levetiracetam (16.0 months; 95%CI, 15.5-19.4; p=0.027). Levetiracetam use during the whole duration of the standard chemoradiation protocol (adjusted Hazard Ratio (aHR) 0.69; 95%CI, 0.52-0.93; p=0.014), O6-Methylguanine-DNA methyltransferase promoter methylation (aHR 0.53; 95%CI, 0.39-0.71; p<0.001), and gross total tumor resection (aHR 0.57; 95%CI, 0.44-0.74; p<0.001) were independent predictors of a longer overall survival. After case matching (n=54 per group), a longer overall survival was found for Levetiracetam use during the whole duration of the standard chemoradiation protocol (HR=0.63; 95%CI, 0.42-0.94, p=0.023).

DISCUSSION

Levetiracetam use during the whole standard chemoradiation protocol possibly improves overall survival of IDH-wildtype glioblastoma patients. It should be considered in the anti-tumor strategy of future multicentric trials.

CLASSIFICATION OF EVIDENCE

This study provides Class III evidence that in individuals with IDH-wildtype glioblastoma, levetiracetam use throughout the duration of standard chemotherapy is associated with longer median overall survival.

Acetylation Profiles in the Metabolic Process of Glioma-Associated Seizures

Objective: We test the hypothesis that lysine acetylation is involved in the metabolic process of glioma-associated seizures (GAS). Methods: We used label-free mass spectrometry-based quantitative proteomics to quantify dynamic changes of protein acetylation between gliomas with seizure (CA1 group) and gliomas without seizure (CA2 group). Furthermore, differences of acetyltransferase and deacetylase expression between CA1 and CA2 groups were performed by a quantitative proteomic study. We further classified acetylated proteins into groups according to cell component, molecular function, and biological process. In addition, metabolic pathways and protein interaction networks were analyzed. Regulated acetyltransferases and acetylated profiles were validated by PRM and Western blot. Results: We detected 169 downregulated lysine acetylation sites of 134 proteins and 39 upregulated lysine acetylation sites of 35 proteins in glioma with seizures based on acetylome. We detected 407 regulated proteins by proteomics, from which ACAT2 and ACAA2 were the differentially regulated enzymes in the acetylation of GAS. According to the KEGG analysis, the upregulated acetylated proteins within the PPIs were mapped to pathways involved in the TCA cycle, oxidative phosphorylation, biosynthesis of amino acids, and carbon metabolism. The downregulated acetylated proteins within the PPIs were mapped to pathways involved in fatty acid metabolism, oxidative phosphorylation, TCA cycle, and necroptosis. Regulated ACAT2 expression and acetylated profiles were validated by PRM and Western blot. Conclusions: The data support the hypothesis that regulated protein acetylation is involved in the metabolic process of GAS, which may be induced by acetyl-CoA acetyltransferases.

Old Stars and New Players in the Brain Tumor Microenvironment

In recent years, the direct interaction between cancer cells and tumor microenvironment (TME) has emerged as a crucial regulator of tumor growth and a promising therapeutic target. The TME, including the surrounding peritumoral regions, is dynamically modified during tumor progression and in response to therapies. However, the mechanisms regulating the crosstalk between malignant and non-malignant cells are still poorly understood, especially in the case of glioma, an aggressive form of brain tumor. The presence of unique brain-resident cell types, namely neurons and glial cells, and an exceptionally immunosuppressive microenvironment pose additional important challenges to the development of effective treatments targeting the TME. In this review, we provide an overview on the direct and indirect interplay between glioma and neuronal and glial cells, introducing new players and mechanisms that still deserve further investigation. We will focus on the effects of neural activity and glial response in controlling glioma cell behavior and discuss the potential of exploiting these cellular interactions to develop new therapeutic approaches with the aim to preserve proper brain functionality.

Tumor type, epilepsy burden, and seizure documentation: experiences at a single center neuro-oncology clinic

Background

Patients with both primary and metastatic brain tumors have significant seizure burden due to their tumor. The management of tumor-related epilepsy (TRE) and optimizing antiepileptic drug (AED) regimens requires collaboration between neurologists and seizure specialists, which is facilitated by seizure documentation in clinic notes. We aim to describe seizure incidence in patients seen in neuro-oncology clinical practice. Further, in the subset of those patients with TRE, we aim to analyze seizure documentation.

Methods

This is a retrospective review of patients with a primary or metastatic brain tumor seen in a neuro-oncology clinic in October 2019. Patients with TRE were included in the analysis of seizure documentation. These notes were analyzed for inclusion of seizure descriptors, terminology, AED regimens, and changes in management.

Results

Of the full cohort of 356 patients, 199 (55.9%) had TRE. Anaplastic astrocytomas had the highest percentage of patients with TRE. The analysis of seizure documentation in patients with TRE revealed that the majority of notes (90.9%) mentioned seizures. Fewer notes (39.6%) provided additional descriptions of the seizures or commented on AED regimens (58.3%). In notes for patients who had seizures within the previous 6 months, seizure descriptors were more likely.

Conclusions

This study defines the TRE burden in a cohort of patients seen in neuro-oncology clinic. Among patients with TRE, our study shows that documentation of many aspects of the characteristics and management of patient seizures can be improved, which would facilitate further analysis of impact on patient care as well as future research.

Efficacy of antiepileptic drugs in glioma patients with epilepsy: a systematic review

Background

Comprehensive data on the efficacy and tolerability of antiepileptic drugs (AED) treatment in glioma patients with epilepsy are currently lacking. In this systematic review, we specifically assessed the efficacy of AEDs in patients with a grade II-IV glioma.

Methods

Electronic databases PubMed/MEDLINE, EMBASE, Web of Science, and Cochrane Library were searched up to June 2020. Three different outcomes for both mono- and polytherapy were extracted from all eligible articles: (i) seizure freedom; (ii) ≥50% reduction in seizure frequency; and (iii) treatment failure. Weighted averages (WA) were calculated for outcomes at 6 and 12 months.

Results

A total of 66 studies were included. Regarding the individual outcomes on the efficacy of monotherapy, the highest seizure freedom rate at 6 months was with phenytoin (WA = 72%) while at 12-month pregabalin (WA = 75%) and levetiracetam (WA = 74%) showed highest efficacy. Concerning ≥50% seizure reduction rates, levetiracetam showed highest efficacy at 6 and 12 months (WAs of 82% and 97%, respectively). However, treatment failure rates at 12 months were highest for phenytoin (WA = 34%) and pregabalin (41%). When comparing the described polytherapy combinations with follow-up of ≥6 months, levetiracetam combined with phenytoin was most effective followed by levetiracetam combined with valproic acid.

Conclusion

Given the heterogeneous patient populations and the low scientific quality across the different studies, seizure rates need to be interpreted with caution. Based on the current limited evidence, with the ranking of AEDs being confined to the AEDs studied, levetiracetam, phenytoin, and pregabalin seem to be most effective as AED monotherapy in glioma patients with epilepsy, with levetiracetam showing the lowest treatment failure rate, compared to the other AEDs studied.

Recurrence risk after a first remote symptomatic seizure in adults: Epilepsy or not?

The ILAE practical definition of epilepsy has a one seizure possibility to diagnose epilepsy after a first seizure if the recurrence risk is very high. The recurrence risk after a first seizure in brain disorders (first remote seizure) is often high, but varies with etiology, so more specific information is needed for clinical practice. This review describes etiology-specific recurrence risks in adults with a first remote seizure in stroke, traumatic brain injury, infections, dementia, multiple sclerosis, and tumors. Most studies are short, single center, and retrospective. Inclusion criteria, outcome ascertainment, and results vary. Few patient categories are clearly above the epilepsy threshold of recurrence risk, and there are surprisingly little data for important etiologies like brain infections. Beside stroke, severe TBI could have a sufficiently high recurrence risk for early epilepsy diagnosis, but more studies are needed, preferably prospective ones. The literature is uninformative regarding which seizures qualify as remote. The clinical implication of the low level of available evidence is that for other etiologies than stroke, seizure recurrence remains the most appropriate indicator of epilepsy for most patients with a first remote seizure. Nonetheless, there are worrying indications of a diagnostic drift, which puts patients with a preexisting brain disorder at risk of misdiagnosis. Although there are drawbacks to an intermediate term like "possible epilepsy," it could perhaps be useful in cases when the recurrence risk is high, but epilepsy criteria are not definitely met after a first remote seizure.

Clinical and genomic factors associated with seizures in meningiomas

OBJECTIVE

The association of seizures with meningiomas is poorly understood. Moreover, any relationship between seizures and the underlying meningioma genomic subgroup has not been studied. Herein, the authors report on their experience with identifying clinical and genomic factors associated with preoperative and postoperative seizure presentation in meningioma patients.

METHODS

Clinical and genomic sequencing data on 394 patients surgically treated for meningioma at Yale New Haven Hospital were reviewed. Correlations between clinical, histological, or genomic variables and the occurrence of preoperative and postoperative seizures were analyzed. Logistic regression models were developed for assessing multiple risk factors for pre- and postoperative seizures. Mediation analyses were also conducted to investigate the causal pathways between genomic subgroups and seizures.

RESULTS

Seventeen percent of the cohort had presented with preoperative seizures. In a univariate analysis, patients with preoperative seizures were more likely to have tumors with a somatic NF2 mutation (p = 0.020), WHO grade II or III tumor (p = 0.029), atypical histology (p = 0.004), edema (p < 0.001), brain invasion (p = 0.009), and worse progression-free survival (HR 2.68, 95% CI 1.30-5.50). In a multivariate analysis, edema (OR 3.11, 95% CI 1.46-6.65, p = 0.003) and atypical histology (OR 2.00, 95% CI 1.03-3.90, p = 0.041) were positive predictors of preoperative seizures, while genomic subgroup was not, such that the effect of an NF2 mutation was indirectly mediated through atypical histology and edema (p = 0.012). Seizure freedom was achieved in 83.3% of the cohort, and only 20.8% of the seizure-free patients, who were more likely to have undergone gross-total resection (p = 0.031), were able to discontinue antiepileptic drug use postoperatively. Preoperative seizures (OR 3.54, 95% CI 1.37-9.12, p = 0.009), recurrent tumors (OR 2.89, 95% CI 1.08-7.74, p = 0.035), and tumors requiring postoperative radiation (OR 2.82, 95% CI 1.09-7.33, p = 0.033) were significant predictors of postoperative seizures in a multivariate analysis.

CONCLUSIONS

Seizures are relatively common at meningioma presentation. While NF2-mutated tumors are significantly associated with preoperative seizures, the association appears to be mediated through edema and atypical histology. Patients who undergo radiation and/or have a recurrence are at risk for postoperative seizures, regardless of the extent of resection. Preoperative seizures may indeed portend a more potentially aggressive molecular entity and challenging clinical course with a higher risk of recurrence.

Seizure Outcome After Surgery for Insular High-Grade Glioma

BACKGROUND

The insular cortex is an eloquent island of mesocortex surrounded by vital structures making this region relatively challenging to neurosurgeons. Historically, lesions in this region were considered too high risk to approach given the strong chance of poor surgical outcome. Advances in recent decades have meant that surgeons can more safely access this eloquent region. Seizure outcome after excision of insular low-grade gliomas is well reported, but little is known about seizure outcomes after excision of insular high-grade gliomas.

METHODS

A retrospective analysis was performed of all patients presenting with new-onset seizures during 2015-2019 who underwent excision of an insular high-grade glioma at 3 regional neurosurgical centers in the United Kingdom.

RESULTS

We identified 38 patients with a mean (SD) age of 45.7 (15.3) years with median follow-up of 21 months. At long-term follow-up, of 38 patients, 23 were seizure-free (Engel class I), 2 had improved seizures (Engel class II), 6 had poor seizure control (Engel class III/IV), and 7 died.

CONCLUSIONS

Excision of insular high-grade gliomas is safe and results in excellent postoperative seizure control.

Differential Effects of a Left Frontal Glioma on the Cortical Thickness and Complexity of Both Hemispheres

Glioma is a type of brain tumor that infiltrates and compresses the brain as it grows. Focal gliomas affect functional connectivity both in the local region of the lesion and the global network of the brain. Any anatomical changes associated with a glioma should thus be clarified. We examined the cortical structures of 15 patients with a glioma in the left lateral frontal cortex and compared them with those of 15 healthy controls by surface-based morphometry. Two regional parameters were measured with 3D-MRI: the cortical thickness (CT) and cortical fractal dimension (FD). The FD serves as an index of the topological complexity of a local cortical surface. Our comparative analyses of these parameters revealed that the left frontal gliomas had global effects on the cortical structures of both hemispheres. The structural changes in the right hemisphere were mainly characterized by a decrease in CT and mild concomitant decrease in FD, whereas those in the peripheral regions of the glioma (left hemisphere) were mainly characterized by a decrease in FD with relative preservation of CT. These differences were found irrespective of tumor volume, location, or grade. These results elucidate the structural effects of gliomas, which extend to the distant contralateral regions.

Under-recognized toxicities of cranial irradiation

Cranial irradiation of primary or metastatic lesions is frequent, historically with 3D-conformal radiation therapy and now with stereotactic radiosurgery and intensity modulation. Evolution of radiotherapy technique is concomitant to systemic treatment evolution permitting long time survival. Thus, physicians have to face underestimated toxicities on long-survivor patients and unknown toxicities from combination of cranial radiotherapy to new therapeutics as targeted therapies and immunotherapies. This article proposes to develop these toxicities, without being exhaustive, to allow a better apprehension of cranial irradiation in current context.

Brain tumor-related epilepsy and risk factors for metastatic brain tumors: analysis of 601 consecutive cases providing real-world data

OBJECTIVE

It is necessary to accurately characterize the epidemiology and trends of brain tumor-related epilepsy (BTE) in patients with metastatic brain tumors. This study aimed to determine the incidence of BTE associated with metastatic brain tumors and retrospectively investigate the risk factors for BTE.

METHODS

This retrospective analysis included 601 of 631 consecutive patients with metastatic brain tumors who received treatment, including surgery, radiotherapy, and/or other treatments. BTE and the clinical course were examined retrospectively. Logistic regression multivariate analyses were performed to identify risk factors for BTE.

RESULTS

BTE was reported in 148 (24.6%) of 601 patients during the entire course. Of these 148 patients, 81 (54.7%) had first-onset epilepsy (13.5% of all patients). Of the 520 cases of nonepileptic onset, 53 were in the prophylactic antiepileptic drug (AED) group. However, 12 of these patients and 55 of the no-prophylactic AED group developed epilepsy during the course of the study. Including these 67 patients, 148 patients were examined as the group of all epilepsy cases during the entire course. In 3 patients, the seizure progressed to status epilepticus. In most patients, the BTE (n = 83, 56.1%) manifested as focal aware seizures. Logistic regression analysis identified young age (p = 0.037), male sex (p = 0.026), breast cancer (p = 0.001), eloquent area (p < 0.001), peritumoral edema (p < 0.001), dissemination (p = 0.013), and maximum tumor volume (p = 0.021) as significant risk factors for BTE. BTE was more common with tumor volumes greater than the cutoff value of 1.92 ml.

CONCLUSIONS

BTE appears to be more likely to occur in cases with young age, male sex, breast cancer, tumors involving eloquent areas, brain edema, dissemination, and giant tumors.

Association between IDH mutational status and tumor-associated epilepsy or venous thromboembolism in patients with grade II and III astrocytoma

In previous studies, isocitrate dehydrogenase (IDH) mutations were associated with tumor-associated epilepsy (TAE) and venous thromboembolism (VTE). We examined the relationship between IDH mutations in grade II/III astrocytomas and TAE/VTE according to the 2016 World Health Organization classification. The clinical data of patients with newly diagnosed grade II/III gliomas who were treated at Tohoku University Hospital from January 2010 to December 2018 were reviewed. Associations between TAE or VTE and the clinical/biological characteristics, histology, and IDH1/2 mutational status in patients with grade II/III gliomas were evaluated. Of the initial 137 patients (290 hospitalizations), 117 patients (203 hospitalizations) were included in the TAE group and 124 patients (213 hospitalizations) were included in the VTE group. Seventy-eight patients (66.7%) in the TAE group were diagnosed with astrocytoma and 38/78 (48.3%) presented with TAE. According to the multivariable analysis, the IDH mutational status and male sex were associated independently with an increased risk of TAE (p < 0.05). Eighty-five patients (68.5%) in the VTE group were diagnosed with astrocytoma. VTE was observed in 16/161 (9.9%) hospitalizations. According to the multivariable analysis, age, diffuse astrocytoma histology, and resection were associated independently with an increased risk of VTE. The decision tree analysis showed that TAE was more frequent in younger patients while VTE was more frequent in older patients. This study demonstrated that the IDH mutational status was associated with TAE but not with VTE. Therefore, a future large-scale study is needed to provide sufficient evidence. TAE was more common in young patients, while VTE was more common in the elderly.

Analysis of intraoperative human brain tissue transcriptome reveals putative risk genes and altered molecular pathways in glioma-related seizures

BACKGROUND

The pathogenesis of glioma-related seizures (GRS) is poorly understood. Here in, we aim to identify putative molecular pathways that lead to the development of GRS.

METHODS

We determined brain transcriptome from intraoperative human brain tissue of patients with either GRS, glioma without seizures (non-GRS), or with idiopathic temporal lobe epilepsy (iTLE). We performed transcriptome-wide comparisons between disease groups tissue from non-epileptic controls (non-EC) to identify differentially-expressed genes (DEG). We compared DEGs to identify those that are specific or common to the groups. Through a gene ontology analysis, we identified molecular pathways enriched for genes with a Log-fold change ≥1.5 or ≤-1.5 and p-value <0.05 compared to non-EC.

RESULTS

We identified 110 DEGs that are associated with GRS vs. non-GRS: 80 genes showed high and 30 low expression in GRS. There was significant overexpression of genes involved in cell-to-cell and glutamatergic signaling (CELF4, SLC17A7, and CAMK2A) and down-regulation of genes involved immune-trafficking (CXCL8, H19, and VEGFA). In the iTLE vs GRS analysis, there were 1098 DEGs: 786 genes were overexpressed and 312 genes were underexpressed in the GRS samples. There was significant enrichment for genes considered markers of oncogenesis (GSC, MYBL2, and TOP2A). Further, there was down-regulation of genes involved in the glutamatergic neurotransmission (vesicular glutamate transporter-2) in the GRS vs. iTLE samples.

CONCLUSIONS

We identified a number of altered processes such as cell-to-cell signaling and interaction, inflammation-related, and glutamatergic neurotransmission in the pathogenesis of GRS. Our findings offer a new landscape of targets to further study in the fields of brain tumors and seizures.

Altered Spontaneous Glutamatergic and GABAergic Activity in the Peritumoral Cortex of Low-Grade Gliomas Presenting With History of Seizures

The peritumoral regions of WHO grade II gliomas, like astrocytoma and oligodendroglioma, have been reported to show epileptiform activities. An imbalance of glutamatergic and GABAergic mechanisms is primarily responsible for the generation of epileptiform activities. Here we have compared the electrophysiological properties of pyramidal neurons in intraoperative peritumoral specimens obtained from glioma patients with (GS) and without (GN) a history of seizures at presentation. Histology and immunohistochemistry were performed to assess the infiltration of proliferating cells at the peritumoral tissues. Whole-cell patch clamp technique was performed to measure the spontaneous glutamatergic and GABAergic activity onto pyramidal neurons in the peritumoral samples of GS (n = 11) and GN (n = 15) patients. The cytoarchitecture of the peritumoral tissues was devoid of Ki67 immuno-positive cells. We observed a higher frequency of spontaneous glutamatergic and GABAergic activities onto pyramidal neurons of the peritumoral samples of GS patients. Our findings suggest that, in spite of similar histopathological features, the pyramidal neurons in the peritumoral samples of GS and GN patients showed differences in spontaneous excitatory and inhibitory synaptic neurotransmission. An alteration in postsynaptic currents may contribute to the spontaneous epileptiform activity in GS patients.

SNO and EANO practice guideline update: Anticonvulsant prophylaxis in patients with newly diagnosed brain tumors

OBJECTIVE

To update the 2000 American Academy of Neurology (AAN) practice parameter on anticonvulsant prophylaxis in patients with newly diagnosed brain tumors.

METHODS

Following the 2017 AAN methodologies, a systematic literature review utilizing PubMed, EMBASE, Cochrane, and Web of Science databases was performed. The studies were rated based on the AAN therapeutic or causation classification of evidence (Class I-IV).

RESULTS

Thirty-seven articles were selected for final analysis. There were limited high level, Class I studies and mostly Class II and III studies. The AAN affirmed the value of these guidelines.

RECOMMENDATIONS

In patients with newly diagnosed brain tumors who have not had a seizure, clinicians should not prescribe anti-epileptic drugs (AEDs) to reduce the risk of seizures (Level A). In brain tumor patients undergoing surgery, there is insufficient evidence to recommend prescribing AEDs to reduce the risk of seizures in the peri- or postoperative period (Level C). There is insufficient evidence to support prescribing valproic acid or levetiracetam with the intent to prolong progression-free or overall survival (Level C). Physicians may consider use of levetiracetam over older AEDs to reduce side effects (Level C). There is insufficient evidence to support using tumor location, histology, grade, molecular/imaging features, when deciding whether or not to prescribe prophylactic AEDs (Level U).

Glioma-Derived TSP2 Promotes Excitatory Synapse Formation and Results in Hyperexcitability in the Peritumoral Cortex of Glioma

Seizures are common in patients with glioma, especially low-grade glioma (LGG). However, the epileptogenic mechanisms are poorly understood. Recent evidence has indicated that abnormal excitatory synaptogenesis plays an important role in epileptogenesis. The thrombospondin (TSP) family is a key regulator of synaptogenesis. Thus, this study aimed to elucidate the role of TSP2 in epileptogenesis in glioma-related epilepsy. The expression of TSP2 was increased in tumor tissue specimens from LGG patients, and this increase may have contributed to an increase in the density of spines and excitatory synapses in the peritumoral area. A glioma cell-implanted rat model was established by stereotactic implantation of wild-type TSP2-expressing, TSP2-overexpressing or TSP2-knockout C6 cells into the neocortex. Similarly, an increase in the density of excitatory synapses was also observed in the peritumoral area of the implanted tumor. In addition, epileptiform discharges occurred in the peritumoral cortex and were positively correlated with the TSP2 level in glioma tissues. Moreover, α2δ1/Rac1 signaling was enhanced in the peritumoral region, and treatment with the α2δ1 antagonist gabapentin inhibited epileptiform discharges in the peritumoral cortex. In conclusion, glioma-derived TSP2 promotes excitatory synapse formation, probably via the α2δ1/Rac1 signaling pathway, resulting in hyperexcitability in the peritumoral cortical networks, which may provide new insight into the epileptogenic mechanisms underlying glioma-related epilepsy.

Influence of Epilepsy on the Quality of Life of Patients with Brain Tumors

Epilepsy is a common consequence of brain tumors, occurring in 35 to 75% of cases. Here we evaluated the influence of epilepsy on the quality of life (QoL) of patients with malignant brain tumors (primary and metastatic) and assessed which areas of function are most affected by epilepsy and brain tumors. Sixty patients undergoing brain tumor surgery at the Neurosurgery Clinic of the 10th Military Research Hospital, Bydgoszcz, Poland (30 with epilepsy and 30 without epilepsy) were studied. Relationships between categorical variables were determined with Pearson’s chi-squared test, while continuous data were analyzed with the Mann-Whitney U-test. A p value < 0.05 was considered statistically significant. A multiple regression model was used for multivariate analysis of QoL. Patients with epilepsy more frequently reported memory disorders as a problem in their daily life. There were trends towards greater impairments in social, professional, and family life, sports and recreational activities, and daily physical activities in brain tumor patients with epilepsy rather than those without epilepsy. Higher frequency and generalized seizures significantly and adversely influenced the ability of patients to leave home and drive vehicles, but a proportion of patients with frequent, generalized seizures continued to drive regardless. Patients with generalized seizures considered the adverse effects of taking medicines as significantly disruptive. Memory disorders significantly affect the QoL of patients with epilepsy, and the importance of stopping driving must be emphasized by all healthcare professionals.

Molecular Classification of Gliomas is Associated with Seizure Control: A Retrospective Analysis

Classically, histologic grading of gliomas has been used to predict seizure association, with low-grade gliomas associated with an increased incidence of seizures compared to high-grade gliomas. In 2016, WHO reclassified gliomas based on histology and molecular characteristics. We sought to determine whether molecular classification of gliomas is associated with preoperative seizure presentation and/or post-operative seizure control across multiple glioma subtypes. All gliomas operated at our institution from 2007 to 2017 were identified based on ICD 9 and 10 billing codes and were retrospectively assessed for molecular classification of the IDH1 mutation, and 1p/19q codeletion. Logistic regression models were performed to assess associations of seizures at presentation as well as post-operative seizures with IDH status and the new WHO integrated classification. Our study included 376 patients: 82 IDH mutant and 294 IDH wildtype. The presence of IDH mutation was associated with seizures at presentation [OR 3.135 (1.818-5.404), p < 0.001]. IDH-mutant glioblastomas presented with seizures less often than other IDH-mutant glioma subtypes grade II and III [OR 0.104 (0.032-0.340), p < 0.001]. IDH-mutant tumors were associated with worse post-operative seizure outcomes, demonstrated by Engel Class [OR 2.666 (1.592-4.464), p < 0.001]. IDH mutation in gliomas is associated with an increased risk of seizure development and worse post-operative seizure control, in all grades except for GBM.

Glutamatergic Mechanisms in Glioblastoma and Tumor-Associated Epilepsy

The progression of glioblastomas is associated with a variety of neurological impairments, such as tumor-related epileptic seizures. Seizures are not only a common comorbidity of glioblastoma but often an initial clinical symptom of this cancer entity. Both, glioblastoma and tumor-associated epilepsy are closely linked to one another through several pathophysiological mechanisms, with the neurotransmitter glutamate playing a key role. Glutamate interacts with its ionotropic and metabotropic receptors to promote both tumor progression and excitotoxicity. In this review, based on its physiological functions, our current understanding of glutamate receptors and glutamatergic signaling will be discussed in detail. Furthermore, preclinical models to study glutamatergic interactions between glioma cells and the tumor-surrounding microenvironment will be presented. Finally, current studies addressing glutamate receptors in glioma and tumor-related epilepsy will be highlighted and future approaches to interfere with the glutamatergic network are discussed.

Neuron and astrocyte aggregation and sorting in three-dimensional neuronal constructs

Aggregation and self-sorting of cells in three dimensional cultures have been described for non-neuronal cells. Despite increased interest in engineered neural tissues for treating brain injury or for modeling neurological disorders in vitro, little data is available on collective cell movements in neuronal aggregates. Migration and sorting of cells may alter these constructs' morphology and, therefore, the function of their neural circuitry. In this work, linear, adhered rat and human 3D neuronal-astrocyte cultures were developed to enable the study of aggregation and sorting of these cells. An in silico model of the contraction, clustering, and cell sorting in the 3D cultures was also developed. Experiments and computational modeling showed that aggregation was mainly a neuron mediated process, and formation of astrocyte-rich sheaths in 3D cultures depended on differential attraction between neurons and astrocytes. In silico model predicted formation of self-assembled neuronal layers in disk-shaped 3D cultures. Neuronal activity patterns were found to correlate with local morphological differences. This model of neuronal and astrocyte aggregation and sorting may benefit future design of neuronal constructs.

Tumor-associated epilepsy in patients with brain metastases: necrosis-to-tumor ratio forecasts postoperative seizure freedom

Surgical resection is highly effective in the treatment of tumor-related epilepsy (TRE) in patients with brain metastases (BM). Nevertheless, some patients suffer from postoperative persistent epilepsy which negatively impacts health-related quality of life. Therefore, early identification of patients with potentially unfavorable seizure outcome after BM resection is important. Patients with TRE that had undergone surgery for BM at the authors’ institution between 2013 and 2018 were analyzed with regard to preoperatively identifiable risk factors for unfavorable seizure outcome. Tumor tissue and tumor necrosis ratios were assessed volumetrically. According to the classification of the International League Against Epilepsy (ILAE), seizure outcome was categorized as favorable (ILAE 1) and unfavorable (ILAE 2–6) after 3 months in order to avoid potential interference with adjuvant cancer treatment. Among all 38 patients undergoing neurosurgical treatment for BM with concomitant TRE, 34 patients achieved a favorable seizure outcome (90%). Unfavorable seizure outcome was significantly associated with larger tumor volumes (p = 0.012), a midline shift > 7 mm (p = 0.025), and a necrosis/tumor volume ratio > 0.2 (p = 0.047). The present study identifies preoperatively collectable risk factors for unfavorable seizure outcome in patients with BM and TRE. This might enable to preselect for highly vulnerable patients with postoperative persistent epilepsy who might benefit from accompanying neuro-oncological expertise during further systemical treatment regimes.

Incidence and risk factors associated with the development of epilepsy in patients with intracranial alveolar echinococcosis

Parasitic infection remains a critical health problem in Ganzi Tibetan Autonomous Prefecture of China. The association of epilepsy and intracranial alveolar echinococcosis (IAE) is still largely unclear. This study primarily aimed to assess both the incidence and possible risk factors of epilepsy in patients with IAE. According to the occurrence of seizures, patients were separated into two different groups consisting of patients with epilepsy and those without epilepsy. Univariate and multivariate logistic regression analysis was used to identify the potential risk factors associated with the development of epilepsy in patients with IAE. A total of 97 patients (42 women, 55 men; age 19-76 years) were enrolled. Epilepsy was observed in almost 20 % of patients with IAE. The use of anti-seizure medications was not standardized, as 83.3 % of female patients of childbearing age used sodium valproate. It was observed that cortical lesions (hazard ratio (HR) = 29.740, P = 0.006) were significantly associated with development of epilepsy. In addition, epilepsy had no significant effect on the overall survival rate of patients with IAE.

Synaptic input to brain tumors: clinical implications

The recent discovery of synaptic connections between neurons and brain tumor cells fundamentally challenges our understanding of gliomas and brain metastases and shows how these tumors can integrate into complex neuronal circuits. Here, we provide an overview of glutamatergic neuron-to-brain tumor synaptic communication (NBTSC) and explore novel therapeutic avenues. First, we summarize current concepts of direct synaptic interactions between presynaptic neurons and postsynaptic glioma cells, and indirect perisynaptic input to metastatic breast cancer cells. We explain how these novel structures drive brain tumor growth and invasion. Second, a vicious cycle of enhanced neuronal activity, including tumor-related epilepsy, and glioma progression is described. Finally, we discuss which future avenues to target NBTSC appear most promising. All in all, further characterization of NBTSC and the exploration of NBTSC-inhibiting therapies have the potential to reveal critical vulnerabilities of yet incurable brain tumors.

Risk factors for the development of epilepsy in patients with brain metastases

BACKGROUND

Current guidelines do not recommend primary prophylactic anti-epileptic drug (AED) therapy for patients with brain metastases (BM). Yet, subgroups of patients at high seizure risk might still benefit from prophylaxis.

METHODS

We identified 799 patients diagnosed with BM by retrospective screening of our electronic chart system. Candidate risk factors for the development of epilepsy were tested by univariate and multivariate Cox regression models.

RESULTS

Epilepsy was diagnosed in 226 of 799 patients (28%). Risk factors for epilepsy in non-operated patients were single BM (P = 0.002, hazard ratio [HR] 3.2, 95% CI: 1.5-6.6) and detection of tumoral hemorrhage (P = 0.008, HR 2.5, 95% CI: 1.3-4.9). Preoperative seizures occurred predominantly in patients with supratentorial BM (P = 0.003, HR 20.78, 95% CI: 2.8-153.4) and lung cancer (P = 0.022; HR 2.0, 95% CI: 1.1-3.6). Postoperative seizures were associated with supratentorial localization (P = 0.017, HR 5.8, 95% CI: 1.4-24.3), incomplete resection (P = 0.005, HR 4.6, 95% CI: 1.6-13.1), and by trend for multiple brain surgeries (P = 0.095, HR 1.9, 95% CI: 0.9-4.0). These risk factors were integrated into a predictive score model for postoperative epilepsy (score sum 0-8). A gradual increase of seizure rates along with higher sum score was confirmed post hoc (score 0 = no seizures; score 8 = 48% seizures). Receiver operating characteristic analysis supported diagnostic accuracy (P = 0.00001, area under the curve = 0.75).

CONCLUSIONS

Here we have defined risk profiles for the development of BM-related epilepsy and derived a score which might help to estimate the risk of postoperative seizures and identify individuals at risk who might benefit from primary prophylactic AED therapy.

A novel nomogram for predicting the risk of epilepsy occurrence after operative in gliomas patients without preoperative epilepsy history

OBJECTIVE

Epilepsy is a common complication in glioma patients after undergoing brain tumor surgery combined with chemotherapy and/or radiotherapy. Whether antiepileptic drug prophylaxis could be used in these patients remains an open question. The purpose of this study was to produce a model for predicting the risk of epilepsy occurrence in such patients.

METHODS

The clinicopathologic data of glioma patients after tumor treatment were reviewed in this study. Univariate and multivariate logistic regression analyses were carried out to analyze the correlation between the clinicopathologic data and the risk of epilepsy occurrence. A nomogram was built according to the multivariate logistic regression model results.

RESULTS

A total of 219 patients with gliomas were reviewed. Univariate analyses revealed that age, WHO glioma classification, CD34, EGFR, Ki67, MGMT, P53 and VIM were significantly associated with the risk of epilepsy occurrence. Multivariate analyses revealed that age, WHO glioma classification, CD34, EGFR, MGMT, and VIM were predictors of risk of epilepsy occurrence. A nomogram of the risk of epilepsy occurrence was built based on statistically significant variables from the multivariate logistic regression analysis. The c-index of the nomogram was 0.755 (95 % confidence interval (CI), 0.742-0.769).

SIGNIFICANCE

This nomogram model provides reliable information about the risk of epilepsy occurrence for oncologists and neurological physicians.

Association of preoperative seizures with tumor metabolites quantified by magnetic resonance spectroscopy in gliomas

Seizures are common in patients with gliomas; however, the mechanisms of epileptogenesis in gliomas have not been fully understood. This study hypothesized that analyzing quantified metabolites using magnetic resonance spectroscopy (MRS) might provide novel insights to better understand the epileptogenesis in gliomas, and specific metabolites might be indicators of preoperative seizures in gliomas. We retrospectively investigated patient information (gender, age at diagnosis of tumor, their survival time) and tumor information (location, histology, genetic features, and metabolites according to MRS) in patients with gliomas. The data were correlated with the incidence of seizure and analyzed statistically. Of 146 adult supratentorial gliomas, isocitrate dehydrogenase (IDH) mutant tumors significantly indicated higher incidence of preoperative seizures than IDH wild-type gliomas. However, MRS study indicated that glutamate concentration in IDH wild-type gliomas was higher than that in IDH mutant gliomas. Glutamate was not associated with high frequency of preoperative seizures in patients with gliomas. Instead, increased total N-acetyl-L-aspartate (tNAA) was significantly associated with them. Moreover, multivariable analysis indicated that increased level of tNAA was an independent predictor of preoperative seizures. According to MRS analysis, tNAA, rather than glutamate, might be a useful to detect preoperative seizures in patient with supratentorial gliomas.

Effect of antiepileptic drugs in glioma patients on self-reported depression, anxiety, and cognitive complaints

Introduction

AEDs have been associated with depression, anxiety, and cognitive impairment, all frequent complications of glioma and its subsequent treatment, with considerable morbidity and an adverse effect on health-related quality of life. This study aimed to determine the independent association between AED use and self-reported depression, anxiety, and subjective cognitive impairment in glioma patients.

Methods

In this multicenter cross-sectional study, depression and anxiety were assessed with the HADS and subjective cognitive impairment was assessed with the MOS-CFS. Univariable logistic regression analyses were performed on all potential confounding predictor variables. Potential confounders were included in the multivariable analyses if p-value < 0.1, to evaluate whether use of AEDs was independently related to depression, anxiety, and/or subjective cognitive impairment.

Results

A total of 272 patients were included. Prevalence of depression differed significantly between patients not using (10%) and using AEDs (21%, unadjusted Odds Ratio [uOR] = 2.29 [95%CI 1.05–4.97], p = 0.037), but after correction for confounders the statistical significant difference was no longer apparent (adjusted Odds Ratio [aOR] = 1.94 [95%CI 0.83–4.50], p = 0.125). Prevalences of anxiety (aOR = 1.17 [95%CI 0.59–2.29], p = 0.659) and subjective cognitive impairment (aOR = 0.83 [95%CI 0.34–2.04], p = 0.684) did not differ significantly before or after adjustment of confounders between patients not using (19% and 16%, respectively) and using AEDs (26% and 21%, respectively).

Conclusions

Our results indicate AED use was not independently associated with concurrent depression, anxiety, or subjective cognitive impairment in glioma patients. Alternative factors seem to have a greater contribution to the risk of developing neuropsychiatric symptoms in glioma patients.

Supplementary Information

The online version contains supplementary material available at 10.1007/s11060-021-03747-1.

Neuro-Oncologic Emergencies

Cancer and cancer therapies have the potential to affect the nervous system in a host of different ways. Cerebral edema, increased intracranial pressure, cerebrovascular events, status epilepticus, and epidural spinal cord compression are among those most often presenting as emergencies. Neurologic side-effects of cancer therapies are often mild, but occasionally result in serious illness. Immunotherapies cause autoimmune-related neurologic side-effects that are generally responsive to immunosuppressive therapies. Emergency management of neuro-oncologic problems benefits from early identification and close collaboration among interdisciplinary team members and patients or surrogate decision-makers.

Top Ten Tips Palliative Care Clinicians Should Know About Seizures at the End of Life

Seizures are physically burdensome and emotionally distressing for patients, families, caregivers, and clinicians. Patients with neurological diseases are at increased risk of having complex, difficult-to-control seizures at the end of life. Palliative care (PC) clinicians asked to provide management of these seizures may not be familiar or comfortable with more complex seizures or epilepsy. A team of neurologists and PC specialists have compiled a list of tips to guide clinicians on how to care for patients having seizures and to support their families/caregivers.

Antiseizure medication in patients with Glioblastoma- a collaborative cohort study

PURPOSE

We investigated, whether epileptic seizures (ES) as presenting symptom in adult patients with GBM are associated with better Overall Survival (OS) compared to ES presenting later during the course of GBM, and efficacy and safety of different antiseizure medications (ASMs).

METHODS

Retrospective consecutive cohort study of adults with GBM: 50 from Norway and 50 from Italy. We compared the time to changing ASM treatments. OS was investigated with a Cox regression model adjusted for time dependency.

RESULTS

Median follow-up was 17 months from GBM diagnosis. ES were the presenting symptom in 49 patients. All patients received ASM treatment. LEV was the first ASM in the majority of patients and the most effective at one year from the first prescription, (p = 0.004). Occurrence of adverse events (AEs) was similar between LEV and other ASMs (p = 0.47). Poorer OS correlated with older age at GBM diagnosis, country and ASM therapy. A negative impact of ASMs on OS was observed for LEV in a univariate and multivariate analysis, and for VPA (only in multivariate analysis), even when adjusted for O6-methylguanine-DNA-methyltransferase (MGMT) methylation status. Patients with ES as the onset symptom of GBM and patients who had first ES later had similar OS (p = 0.87).

CONCLUSION

ES as the GBM debut symptom did not lead to a longer OS. LEV was a more effective ASM compared to other treatments with no differences regarding AEs between LEV and other ASMs. Surprisingly, in our patients LEV and VPA were associated with worse OS than other ASMs. This result should be interpreted with caution due to the retrospective nature of this study along with the many variables which may affect the outcome in this population.

Seizures, Edema, Thrombosis, and Hemorrhages: An Update Review on the Medical Management of Gliomas

Patients affected with gliomas develop a complex set of clinical manifestations that deeply impact on quality of life and overall survival. Brain tumor-related epilepsy is frequently the first manifestation of gliomas or may occur during the course of disease; the underlying mechanisms have not been fully explained and depend on both patient and tumor factors. Novel treatment options derive from the growing use of third-generation antiepileptic drugs. Vasogenic edema and elevated intracranial pressure cause a considerable burden of symptoms, especially in high-grade glioma, requiring an adequate use of corticosteroids. Patients with gliomas present with an elevated risk of tumor-associated venous thromboembolism whose prophylaxis and treatment are challenging, considering also the availability of new oral anticoagulant drugs. Moreover, intracerebral hemorrhages can complicate the course of the illness both due to tumor-specific characteristics, patient comorbidities, and side effects of antithrombotic and antitumoral therapies. This paper aims to review recent advances in these clinical issues, discussing the medical management of gliomas through an updated literature review.

Seizure in Indonesian Glioma Patients: Associated Risk Factors and Impact on Survival

Objective:

Seizure is commonly found in patients with glioma. This study aimed to find risk factors for seizures in Indonesian patients with glioma. We also sought to determine the association between seizure and survival in this patient population.

Methods:

Patients with glioma were enrolled from the Dr. Sardjito General Hospital and other hospitals in Yogyakarta Province, Indonesia. Detailed demographic and clinical data were collected from medical records. DNA extraction and polymerase chain reaction (PCR) were performed to detect IDH1 mutation. Tumor tissue samples were stained by hematoxylin-eosin and classified according to the 2016 World Health Organization (WHO) classification of central nervous system (CNS) tumors. Expression of Ki-67 was detected by immunohistochemistry staining. Survival data were also collected.

Results:

In total, 107 patients were included in the analysis. Age, gender, history of smoking, tumor side, tumor grade, Ki-67 expression, and IDH1 mutation were not associated with seizure. Tumors involving the frontal lobe (p=0.037) and oligodendroglioma histology (p=0.031) were associated with the development of seizures in this study. However, multivariate analysis showed that only oligodendrogial histology was associated with seizure [p=0.032, odds ratio (OR) = 4.77, 95% confidence interval (CI) = 1.146-19.822]. Patients with seizures have significantly longer median overall survival than patients without seizures (69.3±25.01 vs. 10.6±6.14 months, respectively, p=0.04).

Conclusion:

This study showed that seizure in patients with glioma in Indonesia is associated with frontal lobe location and oligodendroglioma histology. Patients with seizures also have significantly longer overall survival.

Scale-Free Analysis of Intraoperative ECoG During Awake Craniotomy for Glioma

BACKGROUND

Electrocorticography (ECoG) has been utilized in many epilepsy cases however, the use of this technique for evaluating electrophysiological changes within tumoral zones is spare. Nonetheless, epileptic activities seem to arise from the neocortex surrounding the gliomas suggesting a link between epileptogenesis and glioma cell infiltration in the peritumoral area. The purpose of this study was to implement novel scale-free measures to assess how cortical physiology is altered by the presence of an invasive brain tumor.

METHODS

Twelve patients undergoing an awake craniotomy for resection of a supratentorial glioma were included. ECoG data over the main tumor and the exposed surroundings was acquired intra-operatively just prior to tumor resection. Six of the patients presented with seizures and had data acquired both in the awake and anesthetic state. The corresponding anatomical location of each electrode in relation to the macroscopically-detectable tumor was recorded using the neuronavigation system based on structural anatomical images obtained pre-operatively. The electrodes were classified into tumoral, healthy or peritumoral based on the macroscopically detectable tumoral tissue from the pre-operative structural MRI.

RESULTS

The electrodes overlying the tumoral tissue revealed higher power law exponent (PLE) values across tumoral area compared to the surrounding tissues. The difference between the awake and anesthetic states was significant in the tumoral and healthy tissue (p < 0.05) but not in the peritumoral tissue. The absence of a significant PLE reduction in the peritumoral tissue from the anesthetic to the awake state could be considered as an index of the presence or absence of infiltration of tumor cells into the peritumoral tissue.

CONCLUSIONS

The current study portrays for the first time distinct power law exponent features in the tumoral tissue, which could provide a potential novel electrophysiological marker in the future. The distinct features seen in the peritumoral tissue of gliomas seem to indicate the area where both the onset of epileptiform activity and the tumor infiltration take place.

Can we use intraoperative high-frequency oscillations to guide tumor-related epilepsy surgery?

Objective

In people with low‐grade intrinsic brain tumors, an epileptic focus is often located close to the lesion. High‐frequency oscillations (HFOs) in electrocorticography (ECoG) might help to delineate this focus. We investigated the relationship between HFOs and low‐grade brain tumors and their potential value for tumor‐related epilepsy surgery.

Methods

We analyzed pre‐ and postresection intraoperative ECoG in 41 patients with refractory epilepsy and a low‐grade lesion. Electrodes were designated as overlying the tumor, adjacent resected tissue (peritumoral), or outside the resection bed using magnetic resonance imaging (MRI) and intraoperative photographs. We then used a semiautomated approach to detect HFOs as either ripples (80–250 Hz) or fast ripples (250–500 Hz).

Results

The rate of fast ripples was higher in electrodes covering tumor and peritumoral tissue than outside the resection (p = .04). Mesiotemporal tumors showed more ripples (p = .002), but not more fast ripples (p = .07), than superficial tumors. Rates of fast ripples were higher in glioma and extraventricular neurocytoma than in ganglioglioma or dysembryoplastic neuroepithelial tumor (DNET). The rate of ripples and fast ripples in postresection ECoG was not higher in patients with residual tumor tissue on MRI than those without. The rate of ripples in postresection ECoG was higher in patients with good than bad seizure outcome (p = .03). Fast ripples outside the resection and in post‐ECoG seem related to seizure recurrence.

Significance

Fast ripples in intraoperative ECoG can be used to help guide resection in tumor‐related epilepsy surgery. Preresection fast ripples occur predominantly in epileptogenic tumor and peritumoral tissue. Fast ripple rates are higher in glioma and extraventricular neurocytoma than in ganglioglioma and DNET.

Seizures Among Patients With Brain Metastases: A Population- and Institutional-Level Analysis

OBJECTIVE

To test the hypothesis that subets of patients with brain metastases (BrM) without seizures at intracranial presentation are at increased risk for developing seizures, we characterized the incidence and risk factors for seizure development among seizure-naive patients with BrMs.

METHODS

We identified 15,863 and 1,453 patients with BrM utilizing Surveillance, Epidemiology, and End Results (SEER)-Medicare data (2008-2016) and Brigham and Women's Hospital/Dana Farber Cancer Institute (2000-2015) institutional data, respectively. Cumulative incidence curves and Fine/Gray competing risks regression were used to characterize seizure incidence and risk factors, respectively.

RESULTS

Among SEER-Medicare and institutional patients, 1,588 (10.0%) and 169 (11.6%) developed seizures, respectively. On multivariable regression of the SEER-Medicare cohort, Black vs White race (hazard ratio [HR] 1.45 [95% confidence interval (CI), 1.22-1.73], p < 0.001), urban vs nonurban residence (HR 1.41 [95% CI, 1.17-1.70], p < 0.001), melanoma vs non-small cell lung cancer (NSCLC) as primary tumor type (HR 1.44 [95% CI, 1.20-1.73], p < 0.001), and receipt of brain-directed stereotactic radiation (HR 1.67 [95% CI, 1.44-1.94], p < 0.001) were associated with greater seizure risk. On multivariable regression of the institutional cohort, melanoma vs NSCLC (HR 1.70 [95% CI, 1.09-2.64], p = 0.02), >4 BrM at diagnosis (HR 1.60 [95% CI, 1.12-2.29], p = 0.01), presence of BrM in a high-risk location (HR 3.62 [95% CI, 1.60-8.18], p = 0.002), and lack of local brain-directed therapy (HR 3.08 [95% CI, 1.45-6.52], p = 0.003) were associated with greater risk of seizure development.

CONCLUSIONS

The role of antiseizure medications among select patients with BrM should be re-explored, particularly for those with melanoma, a greater intracranial disease burden, or BrM in high-risk locations.

Pregnancy and brain tumors; a systematic review of the literature

The incidence of primary brain tumors during pregnancy is uncommon. The etiology of these can range from different genetic syndromes such as Li Fraumeni, neurofibromatosis type I, and hormonal associated tumors. The number of meningiomas gradually tends to increase during pregnancy, suggesting a relationship between non-malignant meningiomas and hormonal changes. Clinical features are non specific or can be misinterpreted with pregnancy symptoms such as headache, vomiting and dizziness. It is worth mentioning that the symptoms due to intracranial tumors are no different in pregnant compared with non pregnant patients. However, retrospective studies in glioma behavior suggested that both tumor volume and growth, increased during pregnancy. These changes were correlated with clinical worsening and increased frequency of seizures. The diagnosis requires a proper neurologic exploration and the support of imaging studies. Treatment of tumors is very controversial since we look for the preservation of both mother and fetus. In theory, the best therapy for the mother will also be the best therapy for the fetus. During pregnancy, ideally the treatment is symptomatic, to preserve the fetus, and definite treatment may be performed after birth; the latter is not always accomplished since patients may present with impending herniation or a malignant tumor for which immediate management is necessary. We intend to give an updated review in the literature on the adequate treatment of brain tumors during pregnancy and the anesthetic management during the definite treatment. Literature data was obtained from Pubmed using the search terms: "Pregnancy", "Brain", "Tumors". A total of forty-three articles were selected.

Preoperative Patient-Reported Outcomes in Suspected Low-Grade Glioma: Markers of Disease Severity and Correlations with Molecular Subtypes

This prospective study aims to determine the overall health-related quality of life (HRQoL), functioning, fatigue, and psychological distress preoperatively in patients with suspected diffuse low-grade glioma (dLGG). We were particularly interested if these parameters differed by molecular tumor subtypes: oligodendroglioma, IDHmut astrocytoma and IDHwt astrocytoma. Fifty-one patients answered self-assessed questionnaires prior to operation (median age 51 years; range 19–75; 19 females [37%]). Thirty-five (69%) patients had IDH-mutated tumors, of which 17 were 1p/19q codeleted (i.e., oligodendroglioma) and 18 non-1p/19q codeleted (i.e., IDHmut astrocytoma). A lower overall generic HRQoL was associated with a high level of fatigue (r_s = −0.49, p < 0.001), visual disorder (r_s = −0.5, p < 0.001), motor dysfunction (r_s = −0.51, p < 0.001), depression (r_s = −0.54, p < 0.001), and reduced functioning. Nearly half of the patients reported high fatigue (23 out of 51 patients) and anxiety (26/51 patients). Patients with IDHwt had worse generic HRQoL, worse functioning, and more severe fatigue, though differences were not statistically significant between the molecular subtypes. In conclusion, fatigue and anxiety are prominent self-assessed symptoms of patients with suspected dLGG in a preoperative setting, but do not seem to be a reliable method to make assumptions of underlying biology or guide treatment decisions.

Seizure outcome in temporal glioblastoma surgery: lobectomy as a supratotal resection regime outclasses conventional gross-total resection

Introduction

The postoperative seizure freedom represents an important secondary outcome measure in glioblastoma surgery. Recently, supra-total glioblastoma resection in terms of anterior temporal lobectomy (ATL) has gained growing attention with regard to superior long-term disease control for temporal-located glioblastoma compared to conventional gross-total resections (GTR). However, the impact of ATL on seizure outcome in these patients is unknown. We therefore analyzed ATL and GTR as differing extents of resection in regard of postoperative seizure control in patients with temporal glioblastoma and preoperative symptomatic seizures.

Methods

Between 2012 and 2018, 33 patients with preoperative seizures underwent GTR or ATL for temporal glioblastoma at the authors’ institution. Seizure outcome was assessed postoperatively and 6 months after tumor resection according to the International League Against Epilepsy (ILAE) classification and stratified into favorable (ILAE class 1) versus unfavorable (ILAE class 2–6).

Results

Overall, 23 out of 33 patients (70%) with preoperative seizures achieved favorable seizure outcome following resection of temporal located glioblastoma. For the ATL group, postoperative seizure freedom was present in 13 out of 13 patients (100%). In comparison, respective rates for the GTR group were 10 out of 20 patients (50%) (p = 0.002; OR 27; 95% CI 1.4–515.9).

Conclusions

ATL in terms of a supra-total resection strategy was associated with superior favorable seizure outcome following temporal glioblastoma resection compared to GTR. Regarding above mentioned survival benefit following ATL compared to GTR, ATL as an aggressive supra-total resection regime might constitute the surgical modality of choice for temporal-located glioblastoma.

Brain tumour patients' use of social media for disease management: Current practices and implications for the future

OBJECTIVE

The role of social media in disease management is evolving. We aimed to define current use of social media for patients with primary brain tumours.

METHODS

This was a single-centre cross-sectional prospective study; a questionnaire was administered on electronic tablets to patients in the Outpatient Department of Royal Melbourne Hospital.

RESULTS

Of the 201 participants, 55.7 % were female and 61.2 % were aged 30-59 years. The Internet was used by 84.5 % of participants, 70.6 % of those used social media. This included social networking sites (33.1 %), wikis (28.1 %) and blogs (14.0 %) to access information, for communication or for interaction related to their brain tumour. Participants indicated preferences for privacy and flexibility and valued when health professionals contributed. Subjective social functioning and activities of daily living benefits were reported from use, however no difference in Health Related Quality of Life was found between social media users and non-users.

CONCLUSIONS

This study is the first to examine social media use in disease management for brain tumour patients and defines its use and potential for targeted online interventions.

PRACTICE IMPLICATIONS

Through identifying concerns regarding current social media sites and determining preferences of patients we have created recommendations to direct design of online content for patients.