Quantifying the prognostic significance in glioblastoma of seizure history at initial presentation: A systematic review and meta-analysis

A selective small-molecule agonist of G protein-gated inwardly-rectifying potassium channels reduces epileptiform activity in mouse models of tumor-associated and provoked seizures

Tumor associated epilepsy is a common and debilitating co-morbidity of brain tumors, for which inadequate treatments are available. Additionally, animal models suggest a potential link between seizures and tumor progression. Our group has previously described a mouse model of diffusely infiltrating glioma and associated chronic epilepsy. G protein-gated inwardly rectifying potassium (GIRK) channels are important regulators of neuronal excitability, but their development as a target of antiseizure medications has been hampered by cross-reactivity with GIRK channels in the heart. Recently GiGA1, a novel GIRK agonist that is highly selective for brain tissue, was developed and shown to have antiseizure properties in an acute chemoconvulsant model. Here, we test GiGA1 ex vivo in our established mouse model of tumor associated epilepsy, demonstrating that a highly selective, small-molecule GIRK agonist can reduce seizure-like activity in the peritumoral region, where neurons and glioma cells interact and from which focal seizures arise.

Do presenting symptoms predict treatment decisions and survival in glioblastoma? Real-world data from 1458 patients in the Swedish brain tumor registry

Background

Glioblastoma is the most common malignant brain tumor in adults. Non-invasive clinical parameters could play a crucial role in treatment planning and serve as predictors of patient survival. Our register-based real-life study aimed to investigate the prognostic value of presenting symptoms.

Methods

Data on presenting symptoms and survival, as well as known prognostic factors, were retrieved for all glioblastoma patients in Sweden registered in the Swedish Brain Tumor Registry between 2018 and 2021. The prognostic impact of different presenting symptoms was calculated using the Cox proportional hazard model.

Results

Data from 1458 adults with pathologically verified IDH wild-type glioblastoma were analyzed. Median survival time was 345 days. The 2-year survival rate was 21.5%. Registered presenting symptoms were focal neurological deficits, cognitive dysfunction, headache, epilepsy, signs of raised intracranial pressure, and cranial nerve symptoms, with some patients having multiple symptoms. Patients with initial cognitive dysfunction had significantly shorter survival than patients without; 265 days (245-285) vs. 409 days (365-453; P < .001). The reduced survival remained after Cox regression adjusting for known prognostic factors. Patients presenting with seizures and patients with headaches had significantly longer overall survival compared to patients without these symptoms, but the difference was not retained in multivariate analysis. Patients with cognitive deficits were less likely to have radical surgery and to receive extensive anti-neoplastic nonsurgical treatment.

Conclusions

This extensive real-life study reveals that initial cognitive impairment acts as an independent negative predictive factor for treatment decisions and adversely affects survival outcomes in glioblastoma patients.

Optimizing Surgical Outcomes for Intracranial Epidermoid Tumors: A Retrospective Analysis of Clinical Predictors, Surgical Decisions, and Patient Clustering

BACKGROUND/OBJECTIVE

Intracranial epidermoid tumors (ETs) are rare, benign lesions that present significant challenges in neurosurgical management due to their propensity to encase vital neurovascular structures. We aimed to evaluate the impact of clinical, demographic, and tumor-specific factors on surgical decisions (gross total resection [GTR] vs. subtotal resection [STR]) and outcomes and identify patient clusters with distinct profiles and outcomes post-resection.

METHODS

We retrospectively analyzed 72 patients with ET treated from 1998 to 2022, employing multivariable logistic regression for GTR versus STR predictors and Kaplan-Meier curves for progression-free survival (PFS). K-prototype clustering classified patients based on clinical data.

RESULTS

The mean age of our cohort was 39.8 ± 20.1 years. About 13.9% of patients had a recurrence, with a median PFS of 108 months (interquartile range: 57 -206). Seizures significantly predicted GTR (P < 0.05), whereas adherence to critical structures reduced GTR likelihood (P < 0.05). Initial surgeries more often achieved GTR, correlating with longer PFS (P < 0.0001) and reduced recurrence (P < 0.01) versus re-operations. Cluster analysis identified three distinct groups, with the initial GTR cluster showing superior PFS and the lowest recurrence (P < 0.0001 and P < 0.01, respectively). Statistically significant predictors of PFS included age and preoperative seizure presence, with older age favoring longer PFS (P < 0.01) and seizures associated with reduced PFS (P < 0.01). In addition, patients with previous surgeries showed a trend toward shorter PFS (P < 0.05).

CONCLUSIONS

This study emphasizes the importance of tailored surgical strategies in managing intracranial ETs, advocating for GTR to optimize long-term outcomes where possible. Future prospective studies are essential to further refine treatment approaches, enhancing survival for ET patients.

Tumor-related epilepsy in high-grade glioma: a large series survival analysis

PURPOSE

Seizures are a common clinical occurrence in high-grade glioma (HGG). While many studies have explored seizure incidence and prevalence in HGG, limited studies have examined the prognostic effect of seizures occurring in the post-diagnosis setting. This study aims to assess the impact of seizure presentation on HGG survival outcomes.

METHODS

Single-center retrospective review identified 950 patients with histologically-confirmed high-grade glioma. Seizure presentation was determined by clinical history and classified as early onset (occurring within 30 days of HGG presentation) or late onset (first seizure occurring after beginning HGG treatment). The primary outcome, hazard ratios for overall survival and progression-free survival, was assessed with multivariable Cox proportional-hazards models. IDH1 mutation status (assessed through immunohistochemistry) was only consistently available beginning in 2015; subgroup analyses were performed in the subset of patients with known IDH1 status.

RESULTS

Epileptic activity before (HR = 0.81, 95% CI = 0.68-0.96, P = 0.017) or after (HR = 0.74, 95% CI = 0.60-0.91, P = 0.005) HGG diagnosis associated with improved overall survival. Additionally, late seizure onset significantly associated with lower odds of achieving partial (OR = 0.25, 95% CI = 0.12-0.53, P = < 0.001) or complete (OR = 0.30, 95% CI = 0.18-0.50, P < 0.001) seizure control than patients with early seizure onset.

CONCLUSIONS

Clinical seizures both at the time of diagnosis and later during the HGG treatment course are associated with improved overall survival. This association potentially persists for both IDH1-wildtype and IDH1-mutant patients, but further study is required.

Focal-to-bilateral tonic-clonic seizures and High-grade CMV-infection are poor survival predictors in Tumor-related Epilepsy Adult-type diffuse gliomas-A single-center study and literature review

Introduction

Previous studies have reported a correlation between a high-grade CMV-infection and an unfavorable prognosis in glioblastoma (GB). Coversely, epilepsy has been associated with a more favorable outcome in GB patients. Despites epilepsy and CMV share similar molecular mechanisms in GB tumoral microenvironment, the correlation between Tumor-Related-Epilepsy (TRE) and CMVinfection remains unexplored. The aim of our study is to examine the correlation between the dregree of CMV infection and seizure types on the survival of TRE Adult-type-diffuse-glioma. To achieve this objective, we conducted a comprehensive literature review to assess our results regarding previous publications.

Methods

We conducted a retrospective-observational study on TRE Adult-type-diffuse-gliomas treated at a single center in Mexico from 2010 to 2018. Tumor tissue and cDNA were analyzed by immunochemistry (IHC) for CMV (IE and LA antigens) at the Karolinska Institute in Sweden, and RT-PCR for CMV-gB in Torreon Mexico, respectively. Bivariate analysis (X2-test) was performed to evaluate the association between subtypes of Adult-type-diffuse-glioma (IDH-mut grade 4 astrocytoma vs. IDH-wt glioblastoma) and the following variables: type of hemispheric involvement (mesial vs. neocortical involvement), degree of CMV infection (<25%vs. >25% infected-tumoral cells) and seizure types [Focal awareness, focal impaired awareness, and FBTCS]. Kaplan Meier and Cox analyses were performed to determine the risk, p < 0.05 was considered statistically significant.

Results

Sixty patients with TRE Adult type diffuse gliomas were included (80% IDH-wt glioblastoma and 20% IDH-mut grade 4astrocytomas). The mean age was 61.5 SD ± 18.4, and 57% were male. Fifty percent of the patients presented with mesial involvement of the hemysphere. Seizure types included focal awareness (15%), focal impaired awareness (43.3%), and FBTCS (41.7%). Ninety percent of cases were treated with Levetiracetam and 33.3% presented Engel-IA postoperative seizure control. More than 90% of samples were positive for CMV-immunohistochemistry (IHC). However, all cDNA analyzed by RT-PCR return negative results. The median of overall survival (OS) was 15 months. High-grade CMV-IE infection (14 vs. 25 months, p<0.001), mesial involvement (12 vs. 18 months, p<0.001), and FBTCS were associated with worse OS (9 vs.18 months for non-FBTCS). Multivariate analysis demonstrated that high-grade CMV infection (HR = 3.689, p=0.002) and FBTCS (HR=7.007, p<0.001) were independent unfavorable survival factors.

Conclusions

CMV induces a proinflammatory tumoral microenvironment that contributes to the developmet of epilepsy. Tumor progression could be associated not only with a higher degree of CMV infection but also to epileptogenesis, resulting in a seizure phenotype chracterized by FBTCS and poor survival outcomes. This study represents the first survival analysis in Latin America to include a representative sample of TRE Adult-type diffuse gliomas considering CMV-infection-degree and distinguishing features (such as FBTCS) that might have potential clinical relevance in this group of patients. Further prospective studies are required to validate these results.

Clinical and Genomic Predictors of Adverse Events in Newly Diagnosed Glioblastoma

PURPOSE

Adverse clinical events cause significant morbidity in patients with GBM (GBM). We examined whether genomic alterations were associated with AE (AE) in patients with GBM.

EXPERIMENTAL DESIGN

We identified adults with histologically confirmed IDH-wild-type GBM with targeted next-generation sequencing (OncoPanel) at Dana Farber Cancer Institute from 2013 to 2019. Seizure at presentation, lymphopenia, thromboembolic events, pseudoprogression, and early progression (within 6 months of diagnosis) were identified as AE. The biologic function of genetic variants was categorized as loss-of-function (LoF), no change in function, or gain-of-function (GoF) using a somatic tumor mutation knowledge base (OncoKB) and consensus protein function predictions. Associations between functional genomic alterations and AE were examined using univariate logistic regressions and multivariable regressions adjusted for additional clinical predictors.

RESULTS

Our study included 470 patients diagnosed with GBM who met the study criteria. We focused on 105 genes that had sequencing data available for ≥ 90% of the patients and were altered in ≥10% of the cohort. Following false-discovery rate (FDR) correction and multivariable adjustment, the TP53, RB1, IGF1R, and DIS3 LoF alterations were associated with lower odds of seizures, while EGFR, SMARCA4, GNA11, BRD4, and TCF3 GoF and SETD2 LoF alterations were associated with higher odds of seizures. For all other AE of interest, no significant associations were found with genomic alterations following FDR correction.

CONCLUSIONS

Genomic biomarkers based on functional variant analysis of a routine clinical panel may help identify AE in GBM, particularly seizures. Identifying these risk factors could improve the management of patients through better supportive care and consideration of prophylactic therapies.

Characteristics and Prognosis of Tumor-Related Epilepsy During Tumor Evolution in Patients With IDH Wild-Type Glioblastoma

BACKGROUND AND OBJECTIVES

Tumor-related epilepsy is a well-known symptom of glioblastoma. However, the particular characteristics of epileptic seizures related to glioblastoma, isocitrate dehydrogenase (IDH)-wild-type is almost unexplored longitudinally during the whole course of the disease. We assessed tumor-related epilepsy and seizure control during tumor evolution and the prognostic significance of tumor-related epilepsy.

METHODS

We performed an observational, retrospective single-center study at one tertiary referral neuro-oncology surgical center (2000-2020). We included adult patients treated for a newly diagnosed supratentorial glioblastoma, IDH-wild-type with available preoperative and postoperative MRI and with available epileptic seizure status at diagnosis. To determine factors associated with tumor-related epilepsy or seizure control, univariate analyses were performed using the χ2 or Fisher exact tests for categorical variables and the unpaired t test or Mann-Whitney rank-sum test for continuous variables. Predictors associated with tumor-related epilepsy and seizure control in unadjusted analysis were entered into backward stepwise logistic regression models.

RESULTS

One thousand six patients were enrolled. The cumulative incidence of tumor-related epilepsy increased during tumor evolution (33.1% at diagnosis, 44.7% after oncologic treatment, 52.4% at progression, and 51.8% at the end-of-life phase) and is related to tumor features (cortex involvement, no necrosis, and small volume). Uncontrolled epileptic seizures increased during tumor evolution (20.1% at diagnosis, 32.0% after oncologic treatment, 46.7% at progression, and 41.1% at the end-of-life phase). Epileptic seizure control after oncologic treatment was related to seizure features (uncontrolled before oncologic treatment and focal-to-bilateral tonic-clonic seizures) and to the extent of resection. Epileptic seizure control at tumor progression was related to seizure features (presence at diagnosis and uncontrolled after oncologic treatment) and to the time to progression. Tumor-related epilepsy at diagnosis was a predictor of a longer overall survival (adjusted hazard ratio, 0.78; 95% CI 0.67-0.90; p < 0.001) independent of age, Karnofsky Performance Status score, tumor location and volume, extent of resection, standard combined chemoradiotherapy, levetiracetam use, and MGMT promoter methylation.

DISCUSSION

The progression of tumor-related epilepsy with the evolution of glioblastoma, IDH-wild-type and the effects of surgery on seizure control argue for proper antiseizure medication and maximal safe resection. Tumor-related epilepsy is an independent predictor of a longer survival.

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.

Novel therapeutic strategies in glioma targeting glutamatergic neurotransmission

High grade gliomas carry a poor prognosis despite aggressive surgical and adjuvant approaches including chemoradiotherapy. Recent studies have demonstrated a mitogenic association between neuronal electrical activity and glioma growth involving the PI3K-mTOR pathway. As the predominant excitatory neurotransmitter of the brain, glutamate signalling in particular has been shown to promote glioma invasion and growth. The concept of the neurogliomal synapse has been established whereby glutamatergic receptors on glioma cells have been shown to promote tumour propagation. Targeting glutamatergic signalling is therefore a potential treatment option in glioma. Antiepileptic medications decrease excess neuronal electrical activity and some may possess anti-glutamate effects. Although antiepileptic medications continue to be investigated for an anti-glioma effect, good quality randomised trial evidence is lacking. Other pharmacological strategies that downregulate glutamatergic signalling include riluzole, memantine and anaesthetic agents. Neuromodulatory interventions possessing potential anti-glutamate activity include deep brain stimulation and vagus nerve stimulation - this contributes to the anti-seizure efficacy of the latter and the possible neuroprotective effect of the former. A possible role of neuromodulation as a novel anti-glioma modality has previously been proposed and that hypothesis is extended to include these modalities. Similarly, the significant survival benefit in glioblastoma attributable to alternating electrical fields (Tumour Treating Fields) may be a result of disruption to neurogliomal signalling. Further studies exploring excitatory neurotransmission and glutamatergic signalling and their role in glioma origin, growth and propagation are therefore warranted.

Risk factors for preoperative and postoperative seizures in patients with glioblastoma according to the 2021 World Health Organization classification

OBJECTIVE

To identify risk factors for developing glioblastoma (GBM) related preoperative (PRS) and postoperative seizures (POS). Also, we aimed to analyze the impact of PRS and POS on survival in a GBM cohort according to the revised 2021 WHO glioma classification.

METHODS

We performed a single-center retrospective cohort study of patients with GBM (according to the 2021 World Health Organization Classification) treated at Mayo Clinic Florida between January 2018 and July 2022. Seizures were stratified into preoperative seizures (PRS) and postoperative seizures (POS, >7 days after surgery). Associations between patients' characteristics and overall survival with PRS and POS were assessed.

RESULTS

One hundred nineteen adults (mean =60.9 years), 49 (41.2 %) females, were identified. The rates of PRS and POS in the cohort were 35.3 % (n = 42) and 37.8 % (n = 45), respectively. Patients with PRS were younger (p = 0.035) and were likely to undergo intraoperative electrocorticography. The incidence of PRS (p = 0.049) and POS (p<0.001) was lower among patients with tumors located in the occipital location. PRS increased the risk of POS after adjusting for age and sex (RR: 2.59, CI = 1.44-4.65, p = 0.001). There was no association between PRS or POS and other patient-related factors, including several tumor molecular markers (TMMs) examined. PRS (p = 0.036), POS (p<0.001), and O6-Methylguanine-DNA Methyltransferase (MGMT) promotor methylation status (p = 0.032) were associated with longer survival time.

CONCLUSIONS

PRS and POS are associated with non-occipital tumor location and longer survival time in patients with GBM. While younger ages predicted PRS, PRS predicted POS. Well-designed prospective studies with larger sample sizes are needed to clarify the influence of TMMs in the genesis of epileptic seizures in patients with GBM.

The complexities underlying epilepsy in people with glioblastoma

Seizures are among the most common clinical signs in people with glioblastoma. Advances over the past 5 years, including new clinical trial data, have increased the understanding of why some individuals with glioblastoma are susceptible to seizures, how seizures manifest clinically, and what implications seizures have for patient management. The pathophysiology of epilepsy in people with glioblastoma relates to a combination of intrinsic epileptogenicity of tumour tissue, alterations in the tumour and peritumoural microenvironment, and the physical and functional disturbance of adjacent brain structures. Successful management of epilepsy in people with glioblastoma remains challenging; factors such as drug-drug interactions between cancer therapies and antiseizure medications, and medication side-effects, can affect seizure outcomes and quality of life. Advances in novel therapies provide some promise for people with glioblastoma; however, the effects of these therapies on seizures are yet to be fully determined. Looking forward, insights into electrical activity as a driver of tumour cell growth and the intrinsic hyperexcitability of tumour tissue might represent useful targets for treatment and disease modification. There is a pressing need for large randomised clinical trials in this field.

Features of epileptiform activity in patients with diagnosed glioblastoma: from genetic and biochemical mechanisms to clinical aspects

Introduction. glioblastomas multiforme (grade Iv gliomas) are common and the most aggressive primary tumors of the brain with very unfavorable prognosis. In all previously published papers on epileptiform activity in glioblastomas, not enough information on encephalogram results is presented.

Aim. To study the features of epileptiform activity in patients with glioblastomas and development of a plan for further study of these patients.

Materials and methods. An analysis of articles from Elsevier, Embase, Scopus, The Cochrane Library, global Health, Russian Science Citation Index (RSCI) databases, Scholar, google, web of Science, pubmed search engines and scientific electronic library CyberLeninka was performed. materials were selected considering journal indexing system and citations, scientific novelty of the studies, statistical significance of the results. publications repeating data from previous articles or describing animal experiments were excluded from analysis.

Results. During the study, data on mechanisms of epileptiform activity pathogenesis, predisposing factors (tumor location in the temporal, frontal or parietal lobes, IDH-1 and / or IDH-2 gene mutations), treatment options in patients with glioblastomas were systemized. Additionally, and original plan of data accumulation for clinical studied taking into account limitations of the previous studies was developed to increase quality of results interpretation.

Conclusion. Epileptiform symptoms in glioblastomas negatively affect patients’ quality of life and lifespan. Currently, researchers actively search for an effective method of treatment of epileptic seizures in patients with glioblastomas. The most effective is combination of temozolomide with valproate and levetiracetam due to good control of seizure frequency, low toxicity, and pharmacological synergy between the drugs.

Effect of perioperative seizures on mortality and recurrence in patients with brain metastases

Objective

To identify the independent risk factors for 30-day perioperative seizures, as well as to evaluate the effect of perioperative seizures on overall mortality and tumor recurrence among patients who underwent surgical resection of brain metastases.

Methods

Patients who underwent surgical resection of brain metastases at our institution between 2011 and 2019 were included. 30-day perioperative seizures were defined as the presence of any preoperative or postoperative seizures diagnosed by a neurosurgeon or neurologist within 30 days of metastases resection. Independent risk factors for 30-day perioperative seizures were evaluated using multivariate logistic regression models. Kaplan-Meier plots and Cox regression models were constructed to evaluate the effects of 30-day perioperative seizures on overall mortality and tumor recurrence. Subgroup analyses were conducted for 30-day preoperative and 30-day postoperative seizures.

Results

A total of 158 patients were included in the analysis. The mean (SD) age was 59.3 (12.0) years, and 20 (12.7%) patients had 30-day perioperative seizures. The presence of 30-day preoperative seizures (OR=41.4; 95% CI=4.76, 924; p=0.002) was an independent risk factor for 30-day postoperative seizures. Multivariate Cox regression revealed that any 30-day perioperative seizure (HR=3.25; 95% CI=1.60, 6.62; p=0.001) was independently and significantly associated with overall mortality but not tumor recurrence (HR=1.95; 95% CI=0.78, 4.91; p=0.154).

Conclusions

Among patients with resected brain metastases, the presence of any 30-day perioperative seizure was independently associated with overall mortality. This suggests that 30-day perioperative seizures may be a prognostic marker of poor outcome. Further research evaluating this association as well as the effect of perioperative antiepileptic drugs in patients with resected brain metastases may be warranted.

Epileptogenesis and Tumorigenesis in Glioblastoma: Which Relationship?

Epilepsy is reported in 29–52% of patients with glioblastoma (GBM) and has an important role in the natural history of this tumor and patients’ life quality. Although GBM is less epileptogenic than lower-grade gliomas, seizures are usually more difficult to control with common antiseizure medications; drug resistance is found in 20% of cases. Recent studies suggest that seizures at the onset of GBM could be a possible favorable independent prognostic factor in patients. Moreover, a growing body of evidence shows that many molecular mechanisms that influence epileptogenesis often regulate GBM growth and invasiveness, sometimes favoring or counteracting the tumor, respectively. The better-characterized players include glutamate, γ-aminobutyric acid, aquaporin-4, and hypoxia-activated molecules. However, currently available data on the molecular basis of epileptogenesis, tumorigenesis, and their relationship is incomplete or discordant and further research is urgently needed on this topic.

The efficacy of temozolomide combined with levetiracetam for glioblastoma (GBM) after surgery: a study protocol for a double-blinded and randomized controlled trial

Background

Temozolomide is applied as the standard chemotherapy agent in patients with glioblastoma (GBM) after surgery. However, the benefit of this treatment for patients is limited by the invasive growth of gliomas and drug resistance. There are indications from fundamental experimental and retrospective studies that levetiracetam has the potential to improve the survival rate of patients with GBM. However, it has yet to be determined whether the combination of temozolomide and levetiracetam is more effective than standard temozolomide chemotherapy. Therefore, we designed a randomized clinical trial to investigate the therapeutic effect of the new combined regime for treating GBM.

Methods/design

This is a double-blind and randomized clinical trial conducted in a single center. One hundred forty-two patients will be recruited and screened for the inclusion and exclusion criteria. Then, eligible participants will be randomly assigned to an experimental group or a control group in a 1:1 ratio. Based on the administration of radiation therapy (RT), participants in the experimental group will be prescribed levetiracetam plus temozolomide chemotherapy for 34 weeks while participants in the control group will receive placebo tablets plus temozolomide for the same duration. A 3-year follow-up will be conducted on all patients after intervention. Accordingly, the primary outcome will be progression-free survival (PFS). The secondary endpoints include overall survival (OS), the Karnofsky Performance Status (KPS), the objective response rate (ORR), and adverse event incidence.

Discussion

It is expected that the results of this trial will provide high-level evidence regarding the clinical benefits of levetiracetam and temozolomide combined in the treatment of GBM.

Trial registration

Chinese Clinical Trial Registry, ChiCTR2100049941. Registered on 14 August 2021

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-022-06168-1.

Initial cognitive impairment predicts shorter survival of patients with glioblastoma

OBJECTIVES

Seizures as presenting symptom of glioblastoma (GBM) are known to predict prolonged survival, whereas the clinical impact of other initial symptoms is less known. Our main objective was to evaluate the influence of different presenting symptoms on survival in a clinical setting. We also assessed lead times, tumour size and localization.

METHODS

Medical records of 189 GBM patients were reviewed regarding the first medical appointment, presenting symptom/s, date of diagnostic radiology and survival. Tumour size, localization and treatment data were retrieved. Overall survival was calculated using Kaplan-Meier and Mann-Whitney U test. Cox regression was used for risk estimation.

RESULTS

Cognitive impairment as the initial symptom was often misinterpreted in primary health care leading to a delayed diagnosis. Initial global symptoms (66% of all patients) were associated with reduced survival compared to no global symptoms (median 8.4 months vs. 12.6 months). Those with the most common cognitive dysfunctions: change of behaviour, memory impairment and/or disorientation had a reduced median survival to 6.4 months. In contrast, seizures (32%) were associated with longer survival (median 11.2 months vs. 8.3 months). Global symptoms were associated with larger tumours than seizures, but tumour size had no linear association with survival. The setting of the first medical appointment was evenly distributed between primary health care and emergency units.

CONCLUSION

Patients with GBM presenting with cognitive symptoms are challenging to identify, have larger tumours and reduced survival. In contrast, epileptic seizures as the first symptom are associated with longer survival and smaller tumours.

Non-invasively measured brain activity and radiological progression in diffuse glioma

Non-invasively measured brain activity is related to progression-free survival in glioma patients, suggesting its potential as a marker of glioma progression. We therefore assessed the relationship between brain activity and increasing tumor volumes on routine clinical magnetic resonance imaging (MRI) in glioma patients. Postoperative magnetoencephalography (MEG) was recorded in 45 diffuse glioma patients. Brain activity was estimated using three measures (absolute broadband power, offset and slope) calculated at three spatial levels: global average, averaged across the peritumoral areas, and averaged across the homologues of these peritumoral areas in the contralateral hemisphere. Tumors were segmented on MRI. Changes in tumor volume between the two scans surrounding the MEG were calculated and correlated with brain activity. Brain activity was compared between patient groups classified into having increasing or stable tumor volume. Results show that brain activity was significantly increased in the tumor hemisphere in general, and in peritumoral regions specifically. However, none of the measures and spatial levels of brain activity correlated with changes in tumor volume, nor did they differ between patients with increasing versus stable tumor volumes. Longitudinal studies in more homogeneous subgroups of glioma patients are necessary to further explore the clinical potential of non-invasively measured brain activity.

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.

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.

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.

Association between supratentorial pediatric high-grade gliomas involved with the subventricular zone and decreased survival: a multi-institutional retrospective study

OBJECTIVE

The subventricular zone (SVZ), housed in the lateral walls of the lateral ventricles, is the largest neurogenic niche in the brain. In adults, high-grade gliomas in contact or involved with the SVZ are associated with decreased survival. Whether this association holds true in the pediatric population remains unexplored. To address this gap in knowledge, the authors conducted this retrospective study in a pediatric population with high-grade gliomas treated at three comprehensive centers in the United States.

METHODS

The authors retrospectively identified 63 patients, age ≤ 21 years, with supratentorial WHO grade III-IV gliomas treated at three academic centers. Basic demographic and clinical data regarding presenting signs and symptoms and common treatment variables were obtained. Preoperative MRI studies were evaluated to assess SVZ contact by tumor and to quantify tumor volume.

RESULTS

Sixty-three patients, including 34 males (54%), had a median age of 12.3 years (IQR 6.50-16.2) and a median tumor volume of 39.4 ml (IQR 19.4-65.8). Tumors contacting the SVZ (SVZ+) were noted in 34 patients (54%) and overall were larger than those not in contact with the SVZ (SVZ-; 51.1 vs 27.3, p = 0.002). The SVZ+ tumors were also associated with decreased survival. However, age, tumor volume, tumor grade, and treatment with chemotherapy and/or radiation were not associated with survival in the 63 patients. In the univariable analysis, near-total resection, gross-total resection, and seizure presentation were associated with increased survival (HR = 0.23, 95% CI 0.06-0.88, p = 0.03; HR = 0.26, 95% CI 0.09-0.74, p = 0.01; and HR = 0.46, 95% CI 0.22-0.97, p = 0.04, respectively). In a multivariable stepwise Cox regression analysis, only SVZ+ tumors remained significantly associated with decreased survival (HR = 1.94, 95% CI 1.03-3.64, p = 0.04).

CONCLUSIONS

High-grade glioma contact with the SVZ neural stem cell niche was associated with a significant decrease in survival in the pediatric population, as it is in the adult population. This result suggests that tumor contact with the SVZ is a general negative prognosticator in high-grade glioma independent of age group and invites biological investigations to understand the SVZ's role in glioma pathobiology.

The survival effect of valproic acid in glioblastoma and its current trend: a systematic review and meta-analysis

Glioblastoma (GBM) can often present with seizure. Attempts have been made to associate the use of anti-epileptic medication valproic acid (VPA) in standard of care management with survival benefit in the past; however, results to date have been conflicting, and most likely subjected to historical bias. This study aimed to quantify the overall survival (OS) effect of VPA in patients with GBM based on the current literature, and identify potential trend-modifying covariates. Searches of 7 electronic databases from inception to April 2018 were conducted following the appropriate guidelines. Hazard ratios (HRs) derived from Cox proportional hazard models, and mean differences (MDs), were analyzed using the random effects model. Meta-regression was used to identify potential trend-modifying covariates. Seven retrospective cohort studies satisfied selection criteria describing 2181 primary GBM diagnoses, with 534 (24%) receiving VPA in their treatment. Overall, VPA was shown to confer a statistically significant OS advantage (HR, 0.71; 95% CI, 0.56-0.91; p < 0.01) compared to the control group by up to 2.4 months (95% CI, 1.51-3.21; p < 0.01). However, upon meta-regression, this survival advantage as inferred by HRs trended towards the null in newer studies (slope, 1.15; p = 0.02) or in studies with older participants (slope, 1.13; p = 0.02). A similar result was seen with MDs. Based on the literature to date, VPA was significantly associated with better OS in GBM patients by 2.4 months when managed by current standard of care. However, this effect was particularly emphasized among older studies or studies conducted in younger participants indicating the need to exercise caution in assuming generalizability of the pooled effect. Overall, there is considerable bias risks in the current interpretation of the literature, and larger, prospective studies are required for validating our findings.