Epilepsy in Adults with Supratentorial Glioblastoma: Incidence and Influence Factors and Prophylaxis in 184 Patients

Efficacy of Personalized Postoperative Epilepsy Management in Patients with Glioblastoma Utilizing IDH1 Gene Assessment

Objective

We explored the correlation between the presence of isocitrate dehydrogenase-1 (IDH1) mutations and the incidence of postoperative epilepsy in patients with glioblastoma, as well as assessed the efficacy of preemptive administration of antiepileptic medications in mitigating the occurrence of postoperative epilepsy.

Methods

Fifty-three patients who received a postoperative pathological diagnosis of glioblastoma, were enrolled in this study. Tumor specimens were subjected to IDH1 gene analysis. The patient cohort was stratified based on their IDH1 mutation status and the administration of prophylactic antiepileptic drugs during the postoperative phase. We subsequently conducted a comparative analysis of postoperative epileptic complications within each patient subgroup.

Results

In the cohort of 53 patients under study, the occurrence of epilepsy was observed in 10 out of 21 patients carrying IDH1 mutations, while 5 out of 32 patients with wild-type IDH1 also experienced epilepsy, revealing a statistically significant difference (P < 0.05). Among the 27 patients who received prophylactic antiepileptic drugs, 6 of them developed epilepsy, whereas 9 out of 26 patients who did not receive prophylactic antiepileptic drugs exhibited concurrent epilepsy, with no statistically significant difference (P > 0.05). However, when performing a subgroup analysis, it was found that 3 out of 12 patients with IDH1 mutations who received prophylactic antiepileptic drugs experienced epilepsy, whereas 7 out of 9 patients who did not receive prophylactic antiepileptic drugs developed epilepsy, demonstrating a statistically significant difference (P < 0.05). Furthermore, within the group of 15 patients with wild-type IDH1, 3 patients who received prophylactic antiepileptic drugs developed epilepsy, while 2 cases of epilepsy occurred among the 17 patients who did not receive prophylactic antiepileptic drugs, with no statistically significant difference (P > 0.05).

Conclusion

In individuals with IDH1 mutant glioblastoma who have undergone surgical resection, the implementation of preventive antiepileptic therapy demonstrates a potential to diminish the occurrence of postoperative epilepsy.

Unexplained Causes of Glioma-Associated Epilepsies: A Review of Theories and an Area for Research

Approximately 30% of glioma patients are able to survive beyond one year postdiagnosis. And this short time is often overshadowed by glioma-associated epilepsy. This condition severely impairs the patient's quality of life and causes great suffering. The genetic, molecular and cellular mechanisms underlying tumour development and epileptogenesis remain incompletely understood, leading to numerous unanswered questions. The various types of gliomas, namely glioblastoma, astrocytoma and oligodendroglioma, demonstrate distinct seizure susceptibility and disease progression patterns. Patterns have been identified in the presence of IDH mutations and epilepsy, with tumour location in cortical regions, particularly the frontal lobe, showing a more frequent association with seizures. Altered expression of TP53, MGMT and VIM is frequently detected in tumour cells from individuals with epilepsy associated with glioma. However, understanding the pathogenesis of these modifications poses a challenge. Moreover, hypoxic effects induced by glioma and associated with the HIF-1a factor may have a significant impact on epileptogenesis, potentially resulting in epileptiform activity within neuronal networks. We additionally hypothesise about how the tumour may affect the functioning of neuronal ion channels and contribute to disruptions in the blood-brain barrier resulting in spontaneous depolarisations.

Postoperative de novo epilepsy after resection of brain arteriovenous malformations: A national database study of 536 patients

OBJECTIVE

We aimed to assess the incidence and risk factors for de novo epilepsy after arteriovenous malformation (AVM) resection and compare them with a nonresection cohort after propensity score matching, utilizing a national database.

METHODS

Utilizing the TriNetX Research Network, we queried cases from January 1, 2004 to March 1, 2022. We included patients of all ages who underwent supratentorial AVM resection, presenting without seizures on or before surgery and without being on antiseizure medications at least 1 day before surgery. The primary outcome was seizures manifesting at least 6 weeks after surgery. Patient characteristics and outcomes were compared between the cohorts with and without postoperative epilepsy. Further cohorts were created to compare cohorts with and without embolization or rupture. After propensity score matching, we compared an additional cohort of patients with an AVM diagnosis who did not undergo resection.

RESULTS

Of the 536 patients (mean age = 38.9 ± 19.6, 52% females) presenting without seizure who underwent AVM resection, 99 (18.5%) developed de novo epilepsy, with a 1-year cumulative incidence of 13.8%. Patients with epilepsy had higher rates of intracerebral hemorrhage, and intracerebral hemorrhage was less common in the embolization cohort. Patients in the ruptured cohort were older and more often males. After propensity score matching with 18 588 patients with AVM diagnosis but no resection, each group consisted of 529 patients, and de novo epilepsy at 1 year was significantly higher in the AVM resection cohort compared to the nonresection cohort (11.5% vs. 3.4%, p < .001).

SIGNIFICANCE

This analysis of 536 patients provides evidence that de novo epilepsy after brain AVM resection occurs at a 1-year cumulative incidence of 13.8%, with a total of 19.4% developing de novo epilepsy. Intracerebral hemorrhage was inconsistently associated with postoperative de novo epilepsy. De novo epilepsy was significantly less frequent after AVM diagnosis without resection.

The Role of Aquaporins in Epileptogenesis-A Systematic Review

Aquaporins (AQPs) are a family of membrane proteins involved in the transport of water and ions across cell membranes. AQPs have been shown to be implicated in various physiological and pathological processes in the brain, including water homeostasis, cell migration, and inflammation, among others. Epileptogenesis is a complex and multifactorial process that involves alterations in the structure and function of neuronal networks. Recent evidence suggests that AQPs may also play a role in the pathogenesis of epilepsy. In animal models of epilepsy, AQPs have been shown to be upregulated in regions of the brain that are involved in seizure generation, suggesting that they may contribute to the hyperexcitability of neuronal networks. Moreover, genetic studies have identified mutations in AQP genes associated with an increased risk of developing epilepsy. Our review aims to investigate the role of AQPs in epilepsy and seizure onset from a pathophysiological point of view, pointing out the potential molecular mechanism and their clinical implications.

Tumor-related epilepsy and post-surgical outcomes: tertiary hospital experience in Vietnam

Seizures have a significant impact on the quality of life of those who suffer. This study aimed to evaluate the variables that influence the incidence of seizures during the perioperative period and effective measures to enhance epilepsy outcomes among individuals undergoing surgical resection of brain tumors. The authors carried out a prospective observational analysis of all patients who experienced seizures before their brain tumor surgery at UMC, HCMC between 2020 and 2022. 54 cases presented with seizures were enrolled for the study, generalized seizure was the most prevalent seizure type (61.1%), followed by focal seizure (29.6%). The majority of patients presented with seizures are those who were diagnosed with glioma. Low-grade gliomas and frontotemporal lobe tumors increase the postoperative risk of seizure. Other predictive factors are a prolonged history of seizure, especially resistant epilepsy and major peritumoral edema. In contrast, gross total resection reduces postoperative seizure incidence. There was correlation between Ki67 proliferation index and seizure incidence in both low-grade and high-grade gliomas. ECoG made insubstantial difference in enhancing the epilepsy surgery outcome. Overall, 88.9% of patients were seizure-free at 6 months of follow-up (Engel Class I), 7.4% were almost seizure-free (Class II), and 3.7% had significant improvement (Class III), figures for 12-month follow-up were 87.0%, 9.3%, and 3.7% respectively. A shorter history of seizure and gross-total resection appear to be associated with a favorable prognosis for seizure control.

Brain tumor related epilepsy: pathophysiological approaches and rational management of antiseizure medication

Background

Brain tumor related epilepsy (BTRE) is a common complication of cerebral tumors and its incidence is highly dependent on the type of tumor, ranging from 10–15% in brain metastases to > 80% in low grade gliomas. Clinical management is challenging and has to take into account aspects beyond the treatment of non-tumoral epilepsy.

Main body

Increasing knowledge about the pathophysiology of BTRE, particularly on glutamatergic mechanisms of oncogenesis and epileptogenesis, might influence management of anti-tumor and BTRE treatment in the future. The first seizure implies the diagnosis of epilepsy in patients with brain tumors. Due to the lack of prospective randomized trials in BTRE, general recommendations for focal epilepsies currently apply concerning the initiation of antiseizure medication (ASM). Non-enzyme inducing ASM is preferable. Prospective trials are needed to evaluate, if AMPA inhibitors like perampanel possess anti-tumor effects. ASM withdrawal has to be weighed very carefully against the risk of seizure recurrence, but can be achievable in selected patients. Permission to drive is possible for some patients with BTRE under well-defined conditions, but requires thorough neurological, radiological, ophthalmological and neuropsychological examination.

Conclusion

An evolving knowledge on pathophysiology of BTRE might influence future therapy. Randomized trials on ASM in BTRE with reliable endpoints are needed. Management of withdrawal of ASMs and permission to drive demands thorough diagnostic as well as neurooncological and epileptological expertise.

Chinese guideline on the application of anti-seizure medications in the perioperative period of supratentorial craniocerebral surgery

Seizures are a common symptom of craniocerebral diseases, and epilepsy is one of the comorbidities of craniocerebral diseases. However, how to rationally use anti-seizure medications (ASMs) in the perioperative period of craniocerebral surgery to control or avoid seizures and reduce their associated harm is a problem. The China Association Against Epilepsy (CAAE) united with the Trauma Group of the Chinese Neurosurgery Society, Glioma Professional Committee of the Chinese Anti-Cancer Association, Neuro-Oncology Branch of the Chinese Neuroscience Society, and Neurotraumatic Group of Chinese Trauma Society, and selected experts for consultancy regarding outcomes from evidence-based medicine in domestic and foreign literature. These experts referred to the existing research evidence, drug characteristics, Chinese FDA-approved indications, and expert experience, and finished the current guideline on the application of ASMs during the perioperative period of craniocerebral surgery, aiming to guide relevant clinical practice. This guideline consists of six sections: application scope of guideline, concepts of craniocerebral surgery-related seizures and epilepsy, postoperative application of ASMs in patients without seizures before surgery, application of ASMs in patients with seizures associated with lesions before surgery, emergency treatment of postoperative seizures, and 16 recommendations.

De novo epilepsy after microsurgical resection of brain arteriovenous malformations

OBJECTIVE

Seizures are the second most common presenting symptom of brain arteriovenous malformations (bAVMs) after hemorrhage. Risk factors for preoperative seizures and subsequent seizure control outcomes have been well studied. There is a paucity of literature on postoperative, de novo seizures in initially seizure-naïve patients who undergo resection. Whereas this entity has been documented after craniotomy for a wide variety of neurosurgically treated pathologies including tumors, trauma, and aneurysms, de novo seizures after bAVM resection are poorly studied. Given the debilitating nature of epilepsy, the purpose of this study was to elucidate the incidence and risk factors associated with de novo epilepsy after bAVM resection.

METHODS

A retrospective review of patients who underwent resection of a bAVM over a 15-year period was performed. Patients who did not present with seizure were included, and the primary outcome was de novo epilepsy (i.e., a seizure disorder that only manifested after surgery). Demographic, clinical, and radiographic characteristics were compared between patients with and without postoperative epilepsy. Subgroup analysis was conducted on the ruptured bAVMs.

RESULTS

From a cohort of 198 patients who underwent resection of a bAVM during the study period, 111 supratentorial ruptured and unruptured bAVMs that did not present with seizure were included. Twenty-one patients (19%) developed de novo epilepsy. One-year cumulative rates of developing de novo epilepsy were 9% for the overall cohort and 8.5% for the cohort with ruptured bAVMs. There were no significant differences between the epilepsy and no-epilepsy groups overall; however, the de novo epilepsy group was younger in the cohort with ruptured bAVMs (28.7 ± 11.7 vs 35.1 ± 19.9 years; p = 0.04). The mean time between resection and first seizure was 26.0 ± 40.4 months, with the longest time being 14 years. Subgroup analysis of the ruptured and endovascular embolization cohorts did not reveal any significant differences. Of the patients who developed poorly controlled epilepsy (defined as Engel class III–IV), all had a history of hemorrhage and half had bAVMs located in the temporal lobe.

CONCLUSIONS

De novo epilepsy after bAVM resection occurs at an annual cumulative risk of 9%, with potentially long-term onset. Younger age may be a risk factor in patients who present with rupture. The development of poorly controlled epilepsy may be associated with temporal lobe location and a delay between hemorrhage and resection.

Converging Mechanisms of Epileptogenesis and Their Insight in Glioblastoma

Glioblastoma (GBM) is the most common and advanced form of primary malignant tumor occurring in the adult central nervous system, and it is frequently associated with epilepsy, a debilitating comorbidity. Seizures are observed both pre- and post-surgical resection, indicating that several pathophysiological mechanisms are shared but also prompting questions about how the process of epileptogenesis evolves throughout GBM progression. Molecular mutations commonly seen in primary GBM, i.e., in PTEN and p53, and their associated downstream effects are known to influence seizure likelihood. Similarly, various intratumoral mechanisms, such as GBM-induced blood-brain barrier breakdown and glioma-immune cell interactions within the tumor microenvironment are also cited as contributing to network hyperexcitability. Substantial alterations to peri-tumoral glutamate and chloride transporter expressions, as well as widespread dysregulation of GABAergic signaling are known to confer increased epileptogenicity and excitotoxicity. The abnormal characteristics of GBM alter neuronal network function to result in metabolically vulnerable and hyperexcitable peri-tumoral tissue, properties the tumor then exploits to favor its own growth even post-resection. It is evident that there is a complex, dynamic interplay between GBM and epilepsy that promotes the progression of both pathologies. This interaction is only more complicated by the concomitant presence of spreading depolarization (SD). The spontaneous, high-frequency nature of GBM-associated epileptiform activity and SD-associated direct current (DC) shifts require technologies capable of recording brain signals over a wide bandwidth, presenting major challenges for comprehensive electrophysiological investigations. This review will initially provide a detailed examination of the underlying mechanisms that promote network hyperexcitability in GBM. We will then discuss how an investigation of these pathologies from a network level, and utilization of novel electrophysiological tools, will yield a more-effective, clinically-relevant understanding of GBM-related epileptogenesis. Further to this, we will evaluate the clinical relevance of current preclinical research and consider how future therapeutic advancements may impact the bidirectional relationship between GBM, SDs, and seizures.

Glutamic Acid and Total Creatine as Predictive Markers for Epilepsy in Glioblastoma by Using Magnetic Resonance Spectroscopy Before Surgery

OBJECTIVE

Epilepsy in glioblastoma patients significantly reduces their quality of life; however, little is known about the association between predicting epilepsy and metabolites in tumors. In this study, we used 3.0-T magnetic resonance imaging and ¹H-magnetic resonance spectroscopy (MRS) to quantify metabolite concentrations in patients with varying epilepsy histories.

METHODS

Fifty-one patients with glioblastoma underwent pretreatment 3.0-T MRI/¹H-MRS scanning. Single-voxel (1.5 cm³) MRS, in an enhanced lesion, was acquired using a double-echo point-resolved spectroscopic sequence with chemical-shift selective water suppression. MRS data were quantified with linear combination model (LC-Model) software. We compared the MRS data between groups with and without epilepsy during the postoperative course (EP).

RESULTS

The ratios of glutamate (Glu) and glutamate + glutamine (Glx) to total creatine (Glu/tCr and Glx/tCr) in the tumor were associated with epilepsy history. The receiver operating characteristic curve analysis showed that a Glu/tCr value of 1.81 was 70% sensitive and 90% specific for the prediction of EP (area under curve: 0.82). In the analysis excluding patients with preoperative epilepsy, a Glu/tCr value of 1.81 was 75% sensitive and 88% specific for the prediction (area under curve: 0.87).

CONCLUSIONS

Intratumoral metabolite concentrations measured using pretreatment 3.0-T MRI/¹H-MRS changed characteristically in the group with EP. Our study suggests that the Glu/tCr ratio in tumors has adequate reliability in predicting EP. Pretreatment MRS is a minimally invasive and simple procedure that can provide useful information on glioblastoma patients.

Postoperative de novo epilepsy after craniotomy: a nationwide register-based cohort study

BACKGROUND AND OBJECTIVES

The risks of postoperative risk of epilepsy after a craniotomy is widely believed to be raised. A study is warranted to quantify the risks for any neurosurgical indication. In this unselected register-based nationwide cohort study with virtually complete follow-up, the short-term and long-term cumulative risks of postoperative de novo epilepsy for all major neurosurgical indications were estimated.

METHODS

The study was based on 8948 first-time craniotomy patients in Denmark 1 January 2005 to 31 December 2015 with follow-up until 31 December 2016. The patients were classified according to their underlying neurosurgical pathology. Patients with preoperative epilepsy were excluded. The postcraniotomy risks of de novo epilepsy were estimated using the Aalen-Johansen estimator in a multistate model.

RESULTS

The overall cumulative 1-year risk of postcraniotomy de novo epilepsy was 13.9% (95% CI 13.2 to 14.6). For patients with intracranial tumour the cumulative 1-year risk was 15.4% (95% CI 14.4 to 16.5), for spontaneous intracranial haemorrhage 11.3% (95% CI 10.1 to 12.6), for traumatic intracranial haemorrhage 11.1% (95% CI 9.6 to 12.9), for cerebral abscess 27.6% (95% CI 22.8 to 33.5) and for congenital malformations 3.8% (95% CI 1.3 to 11.7). The 6-month, 1-year and 5-year risks for all major indications by specific subtypes are provided.

CONCLUSIONS

The cumulative risk of de novo epilepsy following craniotomy is high for patients with any indication for craniotomy, as compared with the background population. The results provide comprehensive data to support future recommendations regarding prophylactic antiepileptic treatment and driving restrictions.

CB2R induces a protective response against epileptic seizures through ERK and p38 signaling pathways

BACKGROUND AND PURPOSE

Epilepsy is a pivotal neurological disorder characterized by the synchronous discharging of neurons to induce momentary brain dysfunction. Temporal lobe epilepsy is the most common type of epilepsy, with seizures originating from the mesial temporal lobe. The hippocampus forms part of the mesial temporal lobe and plays a significant role in epileptogenesis; it also has a vital influence on the mental development of children. In this study, we aimed to explore the effects of CB2 receptor (CB2R) activation on ERK and p38 signaling in nerve cells of a rat epilepsy model.

MATERIALS AND METHODS

We treated Sprague-Dawley rats with pilocarpine to induce an epilepsy model and treated such animals with a CB2R agonist (JWH133) alone or with a CB2R antagonist (AM630). Nissl's stain showed the neuron conditon in different groups. Western blot analyzed the level of p-ERK and p-p38.

RESULTS

JWH133 can increase the latent period of first seizure attack and decrease the Grades IV-V magnitude ratio after the termination of SE. Nissl's stain showed JWH133 protected neurons in the hippocampus while AM630 inhibited the functioning of CB2R in neurons. Western blot analysis showed that JWH133 decreased levels of p-ERK and p-p38, which is found at increased levels in the hippocampus of our epilepsy model. In contrast, AM630 inhibited the protective function of JWH133 and also enhanced levels of p-ERK and p-p38.

CONCLUSIONS

CB2R activation can induce neurons proliferation and survival through activation of ERK and p38 signaling pathways.

How about Levetiracetam in Glioblastoma? An Institutional Experience and Meta-Analysis

Simple Summary

To date, there is a discrepancy regarding the role of antiepileptic drugs on glioblastoma survival. In the present study, based on large institutional cohort and enhanced with a meta-analysis of seven previously published studies, we show a robust association between the perioperative start of levetiracetam treatment with increased overall and progression-free survival in glioblastoma. Our results encourage the initiation of a prospective clinical trial to analyze the antitumor effect of levetiracetam in glioblastoma patients.

Abstract

Despite multimodal treatment, the prognosis of patients with glioblastoma (GBM) remains poor. Previous studies showed conflicting results on the effect of antiepileptic drugs (AED) on GBM survival. We investigated the associations of different AED with overall survival (OS) and progression-free survival (PFS) in a large institutional GBM cohort (n = 872) treated January 2006 and December 2018. In addition, we performed a meta-analysis of previously published studies, including this study, to summarize the evidence on the value of AED for GBM prognosis. Of all perioperatively administered AED, only the use of levetiracetam (LEV) was associated with longer OS (median: 12.8 vs. 8.77 months, p < 0.0001) and PFS (7 vs. 4.5 months, p = 0.001). In the multivariable analysis, LEV was independently associated with longer OS (aHR = 0.74, p = 0.017) and PFS (aHR = 0.68, p = 0.008). In the meta-analysis with 5614 patients from the present and seven previously published studies, outcome benefit for OS (HR = 0.83, p = 0.02) and PFS (HR = 0.77, p = 0.02) in GBM individuals with LEV was confirmed. Perioperative treatment with LEV might improve the prognosis of GBM patients. We recommend a prospective randomized controlled trial addressing the efficacy of LEV in GBM treatment.

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).

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.

Bioinformatics and machine learning methodologies to identify the effects of central nervous system disorders on glioblastoma progression

Glioblastoma (GBM) is a common malignant brain tumor which often presents as a comorbidity with central nervous system (CNS) disorders. Both CNS disorders and GBM cells release glutamate and show an abnormality, but differ in cellular behavior. So, their etiology is not well understood, nor is it clear how CNS disorders influence GBM behavior or growth. This led us to employ a quantitative analytical framework to unravel shared differentially expressed genes (DEGs) and cell signaling pathways that could link CNS disorders and GBM using datasets acquired from the Gene Expression Omnibus database (GEO) and The Cancer Genome Atlas (TCGA) datasets where normal tissue and disease-affected tissue were examined. After identifying DEGs, we identified disease-gene association networks and signaling pathways and performed gene ontology (GO) analyses as well as hub protein identifications to predict the roles of these DEGs. We expanded our study to determine the significant genes that may play a role in GBM progression and the survival of the GBM patients by exploiting clinical and genetic factors using the Cox Proportional Hazard Model and the Kaplan-Meier estimator. In this study, 177 DEGs with 129 upregulated and 48 downregulated genes were identified. Our findings indicate new ways that CNS disorders may influence the incidence of GBM progression, growth or establishment and may also function as biomarkers for GBM prognosis and potential targets for therapies. Our comparison with gold standard databases also provides further proof to support the connection of our identified biomarkers in the pathology underlying the GBM progression.

Preoperative and early postoperative seizures in patients with glioblastoma-two sides of the same coin?

Background

Symptomatic epilepsy is a common symptom of glioblastoma, which may occur in different stages of disease. There are discrepant reports on association between early seizures and glioblastoma survival, even less is known about the background of these seizures. We aimed at analyzing the risk factors and clinical impact of perioperative seizures in glioblastoma.

Methods

All consecutive cases with de-novo glioblastoma treated at our institution between 01/2006 and 12/2018 were eligible for this study. Perioperative seizures were stratified into seizures at onset (SAO) and early postoperative seizures (EPS, ≤21days after surgery). Associations between patients characteristics and overall survival (OS) with SAO and EPS were addressed.

Results

In the final cohort (n = 867), SAO and EPS occurred in 236 (27.2%) and 67 (7.7%) patients, respectively. SAO were independently predicted by younger age (P = .009), higher KPS score (P = .002), tumor location (parietal lobe, P = .001), GFAP expression (≥35%, P = .045), and serum chloride at admission (>102 mmol/L, P = .004). In turn, EPS were independently associated with tumor location (frontal or temporal lobe, P = .013) and pathologic laboratory values at admission (hemoglobin < 12 g/dL, [P = .044], CRP > 1.0 mg/dL [P = 0.036], and GGT > 55 U/L [P = 0.025]). Finally, SAO were associated with gross-total resection (P = .006) and longer OS (P = .030), whereas EPS were related to incomplete resection (P = .005) and poorer OS (P = .009).

Conclusions

In glioblastoma patients, SAO and EPS seem to have quite different triggers and contrary impact on treatment success and OS. The clinical characteristics of SAO and EPS patients might contribute to the observed survival differences.

Prophylactic anticonvulsant therapy in high-grade glioma: A systematic review and meta-analysis of longitudinal studies

INTRODUCTION

It is common practice to prescribe prophylactic antiepileptic drugs (AED) to high-grade glioma (HGG) patients without a history of seizures, yet with limited evidence supporting its use. Ideally, the effectiveness of prophylactic anticonvulsants must outweigh the occurrence of adverse effects and interactions related to AED. The authors conducted a systematic review and metanalysis of longitudinal studies regarding the effectiveness of prophylactic AED in seizure-naïve HGG patients.

MATERIALS AND METHODS

PubMed/MEDLINE, Cochrane Central Register of Controlled trials, Embase and clinicaltrials.gov databases were systematically searched. Of the initial 1773 studies identified, 15 were finally selected for data extraction and analysis. Heterogeneity among studies, pooled hazard ratios, publication bias and sensitivity analyses were performed separately for a 15-study group (HGG patients within larger series of brain tumors) and a 6-study group (exclusively HGG patients).

RESULTS

AED prophylaxis did not significantly reduce the incidence of postoperative seizures compared with controls, both in the 15-study group (Mantel-Haenszel random-effects pooled OR 1.08, 95% CI 0.82-1.43, 2123 patients) and in the 6-study group (pooled OR 1.22, 95% CI 0.77-1.92, 540 patients). However, some issues (paucity of prospective trials, overall moderate-risk of bias, and few studies addressing HGG patients exclusively) preclude firm conclusions against routine prophylactic AED prescription. Reported adverse effects attributable to AED were acceptable in the majority of studies.

CONCLUSIONS

Within the limitations of this review, the results of this metanalysis do not support the routine administration of prophylactic AED to HGG patients without a history of seizures.

Efficacy of perioperative anticonvulsant prophylaxis in seizure-naïve glioma patients: A meta-analysis

The efficacy of perioperative seizure prophylaxis in seizure-naïve glioma patients is still controversial. Thus we conducted this meta-analysis to assess the effectiveness of perioperative prophylactic antiepileptic drugs (AEDs) on postoperative seizures in seizure-naïve glioma for the first time. We systematically searched PubMed, Embase, Weipu (VIP) and Chinese National Knowledge Infrastructure (CNKI) until July 5, 2019 for eligible studies. Fixed or random model was used to calculate the odds ratios in STATA 12.0 software. Subgroup analyses of early postoperative seizure, late postoperative seizure, high-grade glioma (WHOIII-IV) and phenytoin (PHT) or phenobarbital (PB) prophylaxis were conducted. Altogether 1143 seizure-naïve glioma patients from 9 studies were included in this meta-analysis, containing 643 prophylaxed and 503 non-prophylaxed patients. No significant association was detected between perioperative seizure prophylaxis and postoperative seizure occurrence in glioma patients without preoperative seizure history (OR = 0.91, 95% CI = 0.65-1.26, P = 0.56). Perioperative AED prophylaxis showed no significant benefit to postoperative seizures when stratified by early postoperative seizure(within the first postoperative week), late postoperative seizure (after the first postoperative week), high-grade glioma and PHT or PB prophylaxis (all P > 0.05). Current evidence indicated that perioperative seizure prophylaxis did not reduce the occurrence of postoperative seizure in seizure-naïve glioma patients. The pros and cons of perioperative seizure prophylaxis should be considered before the start of perioperative AEDs treatment.

Management of epilepsy in brain tumors

Epilepsy in brain tumors (BTE) may require medical attention for a variety of unique concerns: epileptic seizures, possible serious adverse effects of antineoplastic and antiepileptic drugs (AEDs), physical disability, and/or neurocognitive disturbances correlated to tumor site. Guidelines for the management of tumor-related epilepsies are lacking. Treatment is not standardized, and overall management might differ according to different specialists. The aim of this document was to provide directives on the procedures to be adopted for a correct diagnostic-therapeutic path of the patient with BTE, evaluating indications, risks, and benefits. A board comprising neurologists, epileptologists, neurophysiologists, neuroradiologists, neurosurgeons, neuro-oncologists, neuropsychologists, and patients' representatives was formed. The board converted diagnostic and therapeutic problems into seventeen questions. A literature search was performed in September-October 2017, and a total of 7827 unique records were retrieved, of which 148 constituted the core literature. There is no evidence that histological type or localization of the brain tumor affects the response to an AED. The board recommended to avoid enzyme-inducing antiepileptic drugs because of their interference with antitumoral drugs and consider as first-choice newer generation drugs (among them, levetiracetam, lamotrigine, and topiramate). Valproic acid should also be considered. Both short-term and long-term prophylaxes are not recommended in primary and metastatic brain tumors. Management of seizures in patients with BTE should be multidisciplinary. The panel evidenced conflicting or lacking data regarding the role of EEG, the choice of therapeutic strategy, and timing to withdraw AEDs and recommended high-quality long-term studies to standardize BTE care.

A new acoustic coupling fluid with ability to reduce ultrasound imaging artefacts in brain tumour surgery-a phase I study

Background

A novel acoustic coupling fluid (ACF), with the potential to reduce surgically induced image artefacts during intraoperative ultrasound imaging in brain tumour surgery, has been evaluated with respect to image quality and safety in a clinical phase 1 study.

Methods

Fifteen patients with glioblastoma (WHO grade IV) were included. All adverse events were registered in a 6-month study period. During acquisition of 3D ultrasound image volumes, three different concentrations of the ACF and Ringer’s solution were filled into the resection cavity. The effect of ACF on the ultrasound images was rated by the operating surgeon, and by five independent neurosurgeons evaluating a pair of blinded images from all patients. Images from all patients were analysed by comparing pixel brightness in a noise-affected region and a reference region.

Results

The operating surgeon deemed the ACF images to have less noise than images obtained with Ringers’s solution. The blinded evaluations by the independent neurosurgeons were significantly in favour of ACF (p < 0.0001). The analyses of pixel intensities showed that the ACF images had lower amount of noise than images obtained with Ringer’s solution. No radiological sign of inflammation nor circulatory changes was found in the early postoperative MR images. Of the nine complications registered as serious events in the study period, none was deemed to be caused by the ACF.

Conclusion

The ultrasound (US) images obtained using ACF have significantly less noise than US images obtained with Ringer’s solution. The rate of adverse events was comparable to what has been reported for similar groups of patients.

Clinical practice guidelines for the diagnosis and treatment of adult diffuse glioma-related epilepsy

BACKGROUND

Glioma-related epilepsy (GRE) is defined as symptomatic epileptic seizures secondary to gliomas, it brings both heavy financial and psychosocial burdens to patients with diffuse glioma and significantly decreases their quality of life. To date, there have been no clinical guidelines that provide recommendations for the optimal diagnostic and therapeutic procedures for GRE patients.

METHODS

In March 2017, the Joint Task Force for GRE of China Association Against Epilepsy and Society for Neuro-Oncology of China launched the guideline committee for the diagnosis and treatment of GRE. The guideline committee conducted a comprehensive review of relevant domestic and international literatures that were evaluated and graded based on the Oxford Centre for Evidence-Based Medicine Levels of Evidence, and then held three consensus meetings to discuss relevant recommendations. The recommendations were eventually given according to those relevant literatures, together with the experiences in the diagnosis and treatment of over 3000 GRE cases from 24 tertiary level hospitals that specialize in clinical research of epilepsy, glioma, and GRE in China.

RESULTS

The manuscript presented the current standard recommendations for the diagnostic and therapeutic procedures of GRE.

CONCLUSIONS

The current work will provide a framework and assurance for the diagnosis and treatment strategy of GRE to reduce complications and costs caused by unnecessary treatment. Additionally, it can serve as a reference for all professionals involved in the management of patients with GRE.

Prevalence of symptoms in glioma patients throughout the disease trajectory: a systematic review

BACKGROUND

Glioma patients suffer from a wide range of symptoms which influence quality of life negatively. The aim of this review is to give an overview of symptoms most prevalent in glioma patients throughout the total disease trajectory, to be used as a basis for the development of a specific glioma Patient Reported Outcome Measure (PROM) for early assessment and monitoring of symptoms in glioma patients.

METHODS

A systematic review focused on symptom prevalence in glioma patients in different phases of disease and treatment was performed in MEDLINE, CINAHL and EMBASE according to PRISMA recommendations. We calculated weighted means for prevalence rates per symptom.

RESULTS

The search identified 2.074 unique papers, of which 32 were included in this review. In total 25 symptoms were identified. The ten most prevalent symptoms were: seizures (37%), cognitive deficits (36%), drowsiness (35%), dysphagia (30%), headache (27%), confusion (27%), aphasia (24%), motor deficits (21%), fatigue (20%) and dyspnea (20%).

CONCLUSIONS

Eight out of ten of the most prevalent symptoms in glioma patients are related to the central nervous system and therefore specific for glioma. Our findings emphasize the importance of tailored symptom care for glioma patients and may aid in the development of specific PROMs for glioma patients in different phases of the disease.

CB2R induces a protective response for epileptic seizure via the PI3K 110α-AKT signaling pathway

Epilepsy is a chronic brain disease caused by abnormal discharging in the brain, which induces momentary brain dysfunction. Cannabinoid 2 receptor (CB2R) is expressed in central nervous system (CNS) and serves an important role in the pathogenesis of CNS diseases. The aim of the present study was to explore the effects of CB2R activation on phosphoinositide 3-kinase (PI3K) 110α-protein kinase B (AKT) signaling in an astrocyte model of epilepsy. Rat CTX TNA2 astrocytes were treated with Mg free solution to establish a cell model of epilepsy and were subsequently treated with a CB2R agonist (JWH133) and antagonist (AM630). Cell cycle analysis revealed that treatment using Mg free solution inhibited cell cycle transition. JWH133 facilitated cell cycle progression while AM630 inhibited it. Western blotting results demonstrated that treatment with Mg free solution downregulated the expression of cyclin D1, cyclin E, phosphorylated Retinoblastoma (p-Rb), B-cell lymphoma 2 (Bcl-2), PI3K 110α, p-AKT and p-mammalian target of rapamycin, whereas JWH133 treatment upregulated these proteins. AM630 ameliorated the JWH133-induced upregulation of these proteins. To confirm the involvement of AKT signaling, the AKT inhibitor wortmannin was used. The results revealed that wortmannin inhibited the effect of JWH133 on p-AKT, cyclin D1, p-Rb and Bcl-2 expression. In addition, the effects of JWH133 and AM630 on PI3K 110α-AKT signaling were verified using a rat model of epilepsy. In conclusion, the present study demonstrates that CB2R activation induces astrocyte proliferation and survival via activation of the PI3K 110α-AKT signaling pathway.

Brain tumor related-epilepsy

INTRODUCTION

Gliomas are commonly associated with the development of epilepsy; in some cases the two conditions share common pathogenic mechanisms and may influence each other. Brain tumor related-epilepsy (BTRE) complicates the clinical management of gliomas and can substantially affect daily life.

STATE OF THE ART

The incidence of seizures is high in patients with slow growing tumors located in the frontotemporal regions. However, recent studies suggest that epileptogenesis may be more associated with tumor molecular genetic markers than tumor grade or location. Although the exact mechanism of epileptogenesis in glioma is incompletely understood, glutamate-induced excitotoxicity and disruption of intracellular communication have garnered the most attention.

CLINICAL MANAGEMENT

Management of BTRE requires a multidisciplinary approach involving the use of antiepileptic drugs (AEDs), surgery aided by electrocorticography, and adjuvant chemoradiation.

FUTURE DIRECTIONS

Insight into the mechanisms of glioma growth and epileptogenesis is essential to identify new treatment targets and to develop effective treatment for both conditions. Selecting AEDs tailored to act against known tumor molecular markers involved in the epileptogenesis could enhance treatment value and help inform individualized medicine in BRTE.

Prophylactic anticonvulsants in patients with primary glioblastoma

Glioblastoma is the most common form of primary brain cancer in adults and one of the deadliest of human cancers. Seizures are one of the most frequent presentations of glioblastoma. The use of anti-epileptic drugs (AEDs) in glioblastoma patients suffering from seizures is well accepted. However, the role of long-term AED use in patients with glioblastoma without a history of seizures is controversial. Here, we performed a review of the literature to identify studies that examined the use of AEDs in seizure-free glioblastoma patients. We identified one randomized controlled study suggesting no clinical benefit of seizure prophylaxis in this population. Three of the four retrospective studies identified in our search recapitulated this finding, while the remaining study suggested a benefit for prophylactic AED use. All identified studies were focused on seizure incidence in the post-operative period, ranging from 1 week to long-term follow up. Implications of these findings are reviewed herein.