Tumor-related neurocognitive dysfunction in patients with diffuse glioma: a systematic review of neurocognitive functioning prior to anti-tumor treatment

Predicting Cognitive Functioning for Patients with a High-Grade Glioma: Evaluating Different Representations of Tumor Location in a Common Space

Cognitive functioning is increasingly considered when making treatment decisions for patients with a brain tumor in view of a personalized onco-functional balance. Ideally, one can predict cognitive functioning of individual patients to make treatment decisions considering this balance. To make accurate predictions, an informative representation of tumor location is pivotal, yet comparisons of representations are lacking. Therefore, this study compares brain atlases and principal component analysis (PCA) to represent voxel-wise tumor location. Pre-operative cognitive functioning was predicted for 246 patients with a high-grade glioma across eight cognitive tests while using different representations of voxel-wise tumor location as predictors. Voxel-wise tumor location was represented using 13 different frequently-used population average atlases, 13 randomly generated atlases, and 13 representations based on PCA. ElasticNet predictions were compared between representations and against a model solely using tumor volume. Preoperative cognitive functioning could only partly be predicted from tumor location. Performances of different representations were largely similar. Population average atlases did not result in better predictions compared to random atlases. PCA-based representation did not clearly outperform other representations, although summary metrics indicated that PCA-based representations performed somewhat better in our sample. Representations with more regions or components resulted in less accurate predictions. Population average atlases possibly cannot distinguish between functionally distinct areas when applied to patients with a glioma. This stresses the need to develop and validate methods for individual parcellations in the presence of lesions. Future studies may test if the observed small advantage of PCA-based representations generalizes to other data.

Brain network topology and its cognitive impact in adult glioma survivors

Structural brain network topology can be altered in case of a brain tumor, due to both the tumor itself and its treatment. In this study, we explored the role of structural whole-brain and nodal network metrics and their association with cognitive functioning. Fifty WHO grade 2-3 adult glioma survivors (> 1-year post-therapy) and 50 matched healthy controls underwent a cognitive assessment, covering six cognitive domains. Raw cognitive assessment scores were transformed into w-scores, corrected for age and education. Furthermore, based on multi-shell diffusion-weighted MRI, whole-brain tractography was performed to create weighted graphs and to estimate whole-brain and nodal graph metrics. Hubs were defined based on nodal strength, betweenness centrality, clustering coefficient and shortest path length in healthy controls. Significant differences in these metrics between patients and controls were tested for the hub nodes (i.e. n = 12) and non-hub nodes (i.e. n = 30) in two mixed-design ANOVAs. Group differences in whole-brain graph measures were explored using Mann-Whitney U tests. Graph metrics that significantly differed were ultimately correlated with the cognitive domain-specific w-scores. Bonferroni correction was applied to correct for multiple testing. In survivors, the bilateral putamen were significantly less frequently observed as a hub (pbonf < 0.001). These nodes' assortativity values were positively correlated with attention (r(90) > 0.573, pbonf < 0.001), and proxy IQ (r(90) > 0.794, pbonf < 0.001). Attention and proxy IQ were significantly more often correlated with assortativity of hubs compared to non-hubs (pbonf < 0.001). Finally, the whole-brain graph measures of clustering coefficient (r = 0.685), global (r = 0.570) and local efficiency (r = 0.500) only correlated with proxy IQ (pbonf < 0.001). This study demonstrated potential reorganization of hubs in glioma survivors. Assortativity of these hubs was specifically associated with cognitive functioning, which could be important to consider in future modeling of cognitive outcomes and risk classification in glioma survivors.

Multidisciplinary Management of Isocitrate Dehydrogenase-Mutated Gliomas in a Contemporary Molecularly Defined Era

Mutations in isocitrate dehydrogenase (IDH) genes, an early step in the ontogeny of lower-grade gliomas, induce global epigenetic changes characterized by a hypermethylation phenotype and are critical to tumor classification, treatment decision making, and estimation of patient prognosis. The introduction of IDH inhibitors to block the oncogenic neomorphic function of the mutated protein has resulted in new therapeutic options for these patients. To appreciate the implications of these recent IDH inhibitor results, it is important to juxtapose historical outcomes with chemoradiotherapy. Herein, we rationally evaluate recent IDH inhibitor data within historical precedents to guide contemporary decisions regarding the role of observation, maximal safe resection, adjuvant therapies, and the import of patient and tumor variables. The biological underpinnings of the IDH pathway and the mechanisms, impact, and limitations of IDH inhibitors, the actual magnitude of tumor regression and patient benefit, and emergence of resistance pathways are presented to guide future trial development. Management in the current, molecularly defined era will require careful patient selection and risk factor assessment, followed by an open dialog about the results of studies such as INDIGO, as well as mature data from legacy trials, and a discussion about risk-versus-benefit for the choice of treatment, with multidisciplinary decision making as an absolute prerequisite.

Cognitive functioning in untreated glioma patients: The limited predictive value of clinical variables

BACKGROUND

Previous research identified many clinical variables that are significantly related to cognitive functioning before surgery. It is not clear whether such variables enable accurate prediction for individual patients' cognitive functioning because statistical significance does not guarantee predictive value. Previous studies did not test how well cognitive functioning can be predicted for (yet) untested patients. Furthermore, previous research is limited in that only linear or rank-based methods with small numbers of variables were used.

METHODS

We used various machine learning models to predict preoperative cognitive functioning for 340 patients with glioma across 18 outcome measures. Predictions were made using a comprehensive set of clinical variables as identified from the literature. Model performances and optimized hyperparameters were interpreted. Moreover, Shapley additive explanations were calculated to determine variable importance and explore interaction effects.

RESULTS

Best-performing models generally demonstrated above-random performance. Performance, however, was unreliable for 14 out of 18 outcome measures with predictions worse than baseline models for a substantial number of train-test splits. Best-performing models were relatively simple and used most variables for prediction while not relying strongly on any variable.

CONCLUSIONS

Preoperative cognitive functioning could not be reliably predicted across cognitive tests using the comprehensive set of clinical variables included in the current study. Our results show that a holistic view of an individual patient likely is necessary to explain differences in cognitive functioning. Moreover, they emphasize the need to collect larger cross-center and multimodal data sets.

Application of a Standardized Treatment Paradigm as a Strategy to Achieve Optimal Onco-Functional Balance in Glioma Surgery

BACKGROUND

Gliomas, characterized by their invasive persistence and tendency to affect critical brain regions, pose a challenge in surgical resection due to the risk of neurological deficits. This study focuses on a personalized approach to achieving an optimal onco-functional balance in glioma resections, emphasizing maximal tumor removal while preserving the quality of life.

METHODS

A retrospective analysis of 57 awake surgical resections of gliomas at the National University Hospital, Singapore, was conducted. The inclusion criteria were based on diagnosis, functional boundaries determined by direct electrical stimulation, preoperative Karnofsky Performance Status score, and absence of multifocal disease on MRI. The treatment approach included comprehensive neuropsychological evaluation, determination of suitability for awake surgery, and standard asleep-awake-asleep anesthesia protocol. Tumor resection techniques and postoperative care were systematically followed.

RESULTS

The study included 53 patients (55.5% male, average age 39 years), predominantly right-handed. Over half reported seizures as their chief complaint. Tumors were mostly low-grade gliomas. Positive mapping of the primary motor cortex was conducted in all cases, with awake surgery completed in 77.2% of cases. New neurological deficits were observed in 26.3% of patients at 1 month after operation; most showed significant improvement at 6 months.

CONCLUSION

The standardized treatment paradigm effectively achieved an optimal onco-functional balance in glioma patients. While some patients experienced neurological deficits postoperatively, the majority recovered to their preoperative baseline within 3 months. The approach prioritizes patient empowerment and customized utilization of functional mapping techniques, considering the challenge of preserving diverse languages in a multilingual patient population.

Molecular Determinants of Neurocognitive Deficits in Glioma: Based on 2021 WHO Classification

Cognitive impairment is a common feature among patients with diffuse glioma. The objective of the study is to investigate the relationship between preoperative cognitive function and clinical as well as molecular factors, firstly based on the new 2021 World Health Organization's updated classification of central nervous system tumors. A total of 110 diffuse glioma patients enrolled underwent preoperative cognitive assessments using the Mini-Mental State Examination and Montreal Cognitive Assessment. Clinical information was collected from medical records, and gene sequencing was performed to analyze the 18 most influenced genes. The differences in cognitive function between patients with and without glioblastoma were compared under both the 2016 and 2021 WHO classification of tumors of the central nervous system to assess their effect of differentiation on cognition. The study found that age, tumor location, and glioblastoma had significant differences in cognitive function. Several genetic alterations were significantly correlated with cognition. Especially, IDH, CIC, and ATRX are positively correlated with several cognitive domains, while most other genes are negatively correlated. For most focused genes, patients with a low number of genetic alterations tended to have better cognitive function. Our study suggested that, in addition to clinical characteristics such as age, histological type, and tumor location, molecular characteristics play a crucial role in cognitive function. Further research into the mechanisms by which tumors affect brain function is expected to enhance the quality of life for glioma patients. This study highlights the importance of considering both clinical and molecular factors in the management of glioma patients to improve cognitive outcomes.

Neurorehabilitation for Adults with Brain and Spine Tumors

Central nervous system (CNS) malignancies (i.e. brain and spine tumors) and their treatments can result in a multitude of neurologic deficits. Patients with CNS malignancies experience physical, cognitive, and psychosocial sequelae that can impact their mobility and quality of life. Neurorehabilitation can play a critical role in maintaining independence, preventing disability, and optimizing safety with activities of daily living. This review provides an overview of the neurorehabilitation approaches for patients with CNS malignancies, neurologic impairments frequently treated, and rehabilitation interventions in various health care settings. In addition, we will highlight rehabilitative outcomes between patients with nononcologic neurologic conditions compared to brain and spine tumors. Finally, we address medical challenges that may impact rehabilitation care in these medically complex cancer patients.

Tumor location and neurocognitive function-Unravelling the association and identifying relevant anatomical substrates in intra-axial brain tumors

Background

Neurocognitive function is a key outcome indicator of therapy in brain tumors. Understanding the underlying anatomical substrates involved in domain function and the pathophysiological basis of dysfunction can help ameliorate the effects of therapy and tailor directed rehabilitative strategies.

Methods

Hundred adult diffuse gliomas were co-registered onto a common demographic-specific brain template to create tumor localization maps. Voxel-based lesion symptom (VLSM) technique was used to assign an association between individual voxels and neuropsychological dysfunction in various domains (attention and executive function (A & EF), language, memory, visuospatial/constructive abilities, and visuomotor speed). The probability maps thus generated were further co-registered to cortical and subcortical atlases. A permutation-based statistical testing method was used to evaluate the statistically and clinically significant anatomical parcels associated with domain dysfunction and to create heat maps.

Results

Neurocognition was affected in a high proportion of subjects (93%), with A & EF and memory being the most affected domains. Left-sided networks were implicated in patients with A & EF, memory, and language deficits with the perisylvian white matter tracts being the most common across domains. Visuospatial dysfunction was associated with lesions involving the right perisylvian cortical regions, whereas deficits in visuomotor speed were associated with lesions involving primary visual and motor output pathways.

Conclusions

Significant baseline neurocognitive deficits are prevalent in gliomas. These are multidomain and the perisylvian network especially on the left side seems to be very important, being implicated in dysfunction of many domains.

Longitudinal assessment of quality of life, neurocognition, and psychopathology in patients with low-grade glioma on first-line temozolomide: A feasibility study

Background

The treatment timing and choice after neurosurgical resection in patients with newly diagnosed diffuse low-grade glioma (DLGG) remain controversial. Indeed, the effect of such treatments must be balanced with the possible side effects. This study evaluated the feasibility of longitudinal exhaustive quality of life (QoL) and neuropsychological assessments in patients with DLGG receiving first-line temozolomide.

Methods

QoL, neurocognition, and psychological disorders were assessed prospectively until disease progression, using testing, clinician-reported, and self-reported questionnaires. The primary endpoint was the participation and adherence to this complete assessment at Baseline (before temozolomide initiation), months 6 and 12 of treatment, and month 6 post-treatment. The QoL and neuropsychological changes over time also were described.

Results

Twenty-six of the twenty-nine eligible patients were enrolled (participation rate: 89.7%, 95% CI: 72.6-97.8). The adherence rate was 95.7% (95% CI: 78.1-99.9; n = 23 because 3 patients progressed in the first 12 months of treatment). Up to month 6 post-treatment, QoL and fatigue remained stable (EORTC QLQC30 and BN20, MFI-20); some specific symptoms were transitory. Both subjective (FACT-Cog) and objective (Z-scores of neurocognitive tests) neurocognitive outcomes remained stable or tended to improve. The percentage of patients with severe depression (BDI-II), anxiety (STAI-Y), or anger (STAXI-II) was stable over time.

Conclusions

This prospective study demonstrated the feasibility of an exhaustive and longitudinal evaluation of QoL, neurocognition, and psychological disorders, with high acceptability by patients with DLGG undergoing chemotherapy. First-line temozolomide seems to have limited short-term effects on QoL and neurocognition. These findings must be confirmed in the long term and in a larger cohort.

The involvement of brain regions associated with lower KPS and shorter survival time predicts a poor prognosis in glioma

Background

Isocitrate dehydrogenase-wildtype glioblastoma (IDH-wildtype GBM) and IDH-mutant astrocytoma have distinct biological behaviors and clinical outcomes. The location of brain tumors is closely associated not only with clinical symptoms and prognosis but also with key molecular alterations such as IDH. Therefore, we hypothesize that the key brain regions influencing the prognosis of glioblastoma and astrocytoma are likely to differ. This study aims to (1) identify specific regions that are associated with the Karnofsky Performance Scale (KPS) or overall survival (OS) in IDH-wildtype GBM and IDH-mutant astrocytoma and (2) test whether the involvement of these regions could act as a prognostic indicator.

Methods

A total of 111 patients with IDH-wildtype GBM and 78 patients with IDH-mutant astrocytoma from the Cancer Imaging Archive database were included in the study. Voxel-based lesion-symptom mapping (VLSM) was used to identify key brain areas for lower KPS and shorter OS. Next, we analyzed the structural and cognitive dysfunction associated with these regions. The survival analysis was carried out using Kaplan-Meier survival curves. Another 72 GBM patients and 48 astrocytoma patients from Harbin Medical University Cancer Hospital were used as a validation cohort.

Results

Tumors located in the insular cortex, parahippocampal gyrus, and middle and superior temporal gyrus of the left hemisphere tended to lead to lower KPS and shorter OS in IDH-wildtype GBM. The regions that were significantly correlated with lower KPS in IDH-mutant astrocytoma included the subcallosal cortex and cingulate gyrus. These regions were associated with diverse structural and cognitive impairments. The involvement of these regions was an independent predictor for shorter survival in both GBM and astrocytoma.

Conclusion

This study identified the specific regions that were significantly associated with OS or KPS in glioma. The results may help neurosurgeons evaluate patient survival before surgery and understand the pathogenic mechanisms of glioma in depth.

Identifying brain tumor patients' subtypes based on pre-diagnostic history and clinical characteristics: a pilot hierarchical clustering and association analysis

Introduction

Central nervous system (CNS) tumors are severe health conditions with increasing incidence in the last years. Different biological, environmental and clinical factors are thought to have an important role in their epidemiology, which however remains unclear.

Objective

The aim of this pilot study was to identify CNS tumor patients' subtypes based on this information and to test associations with tumor malignancy.

Methods

90 patients with suspected diagnosis of CNS tumor were recruited by the Neurosurgery Unit of IRCCS Neuromed. Patients underwent anamnestic and clinical assessment, to ascertain known or suspected risk factors including lifestyle, socioeconomic, clinical and psychometric characteristics. We applied a hierarchical clustering analysis to these exposures to identify potential groups of patients with a similar risk pattern and tested whether these clusters associated with brain tumor malignancy.

Results

Out of 67 patients with a confirmed CNS tumor diagnosis, we identified 28 non-malignant and 39 malignant tumor cases. These subtypes showed significant differences in terms of gender (with men more frequently presenting a diagnosis of cancer; p = 6.0 ×10-3) and yearly household income (with non-malignant tumor patients more frequently earning ≥25k Euros/year; p = 3.4×10-3). Cluster analysis revealed the presence of two clusters of patients: one (N=41) with more professionally active, educated, wealthier and healthier patients, and the other one with mostly retired and less healthy men, with a higher frequency of smokers, personal history of cardiovascular disease and cancer familiarity, a mostly sedentary lifestyle and generally lower income, education and cognitive performance. The former cluster showed a protective association with the malignancy of the disease, with a 74 (14-93) % reduction in the prevalent risk of CNS malignant tumors, compared to the other cluster (p=0.026).

Discussion

These preliminary data suggest that patients' profiling through unsupervised machine learning approaches may somehow help predicting the risk of being affected by a malignant form. If confirmed by further analyses in larger independent cohorts, these findings may be useful to create potential intelligent ranking systems for treatment priority, overcoming the lack of histopathological information and molecular diagnosis of the tumor, which are typically not available until the time of surgery.

Cognition, Emotional States and Health-Related Quality of Life in Awake Craniotomy for Glioma: A Case Series

BACKGROUND

Awake craniotomy is an effective procedure for optimizing the onco-functional balance of resections in glioma. However, limited data exists on the cognition, emotional states, and health-related quality of life (HRQoL) of patients with glioma who undergo awake craniotomy. This study aims to describe 1) perioperative cognitive function and emotional states in a multilingual Asian population, 2) associations between perioperative cognitive function and follow-up HRQoL, and 3) associations between preoperative emotional states and follow-up HRQoL.

METHODS

This is a case series of 14 adult glioma patients who underwent awake craniotomy in Singapore. Cognition was assessed with the Montreal Cognitive Assessment and the Repeatable Battery for the Assessment of Neuropsychological Status, emotional states with the Depression, Anxiety and Stress Scale-21 Items, and HRQoL using the EuroQol-5D-5L, the European Organisation for Research and Treatment of Cancer (EORTC) QLQ-C30, and the European Organisation for Research and Treatment of Cancer (EORTC) QLQ-BN20.

RESULTS

Patients with better preoperative cognitive scores on all domains reported better HRQoL. Better postoperative immediate memory and language scores were associated with better HRQoL. Moderate preoperative depression scores and mild and moderate preoperative stress scores were associated with poorer HRQoL compared to scores within the normal range. Mild preoperative anxiety scores were associated with better HRQoL compared to scores within the normal range.

CONCLUSION

This descriptive case series showed that patients with higher preoperative cognitive scores reported better follow-up HRQoL, while patients who reported more preoperative depressive and stress symptomatology reported worse follow-up HRQoL. Future analytical studies may help to draw conclusions about whether perioperative cognition and emotional states predict HRQoL on follow-up.

Neurorehabilitation in brain tumours: evidences and suggestions for spreading of knowledge and research implementation

PURPOSE OF REVIEW

The last few decades have seen an increase in life expectancy in brain tumour patients; however, many patients report sensory-motor and cognitive disabilities due to the tumour itself, but also to the effect of anticancer treatments (surgery, radiotherapy, chemotherapy), supportive treatments, as well as individual patient factors. This review outlines the principles on which to base neurorehabilitation treatments, with the aim of stimulating an early rehabilitative management, in order to reduce disability and functional limitation and improve the quality of life of the persons affected by brain tumour.

RECENT FINDINGS

Although not definitive, evidences suggest that an early neurorehabilitative evaluation, performed with a multidisciplinary approach, may identify the different functional impairments that can affect people with brain tumour. Furthermore, identifying and classifying the person's level of functioning is useful for designing achievable recovery goals, through the implementation of tailored multidisciplinary rehabilitation programs. The involvement of different professional figures allows to treat all the components (physical, cognitive, psychological and participation) of the person, and to redesign one's life project, lastly improving the quality of life.

SUMMARY

Overall, the evidences suggest a critical need for the development of this clinical area by spreading the concept of rehabilitation among neuro-oncologists and producing high quality research.

White matter tracts contribute selectively to cognitive functioning in patients with glioma

Objective

The functional organization of white matter (WM) tracts is not well characterized, especially in patients with intrinsic brain tumors where complex patterns of tissue injury, compression, and neuroplasticity may be present. This study uses diffusion tensor imaging (DTI) to investigate the relationships between WM tract disruption and cognitive deficits in glioma patients.

Methods

Seventy-nine patients with glioma underwent preoperative DTI and neuropsychological testing. Thirteen WM tracts were reconstructed bilaterally. Fractional anisotropy and streamline number were obtained for each tract as indices of connectivity. Univariate regression models were used to model the association between WM tract connectivity and neuropsychological outcomes.

Results

Glioma patients exhibited variable injury to WM tracts and variable cognitive deficits on validated neuropsychological tests. We identified 16 age-adjusted associations between WM tract integrity and neuropsychological function. The left inferior frontal-occipital fasciculus (IFOF) predicted list learning and dominant-hand fine motor dexterity. The right IFOF predicted non-dominant-hand fine motor dexterity and visuospatial index scores. The left inferior longitudinal fasciculus (ILF) predicted immediate memory list learning and index scores. The right ILF predicted non-dominant-hand fine motor dexterity and backward digit span scores. The left superior longitudinal fasciculus (SLF) I predicted processing speed. The left SLF III predicted list learning, immediate memory index scores, phonemic fluency, and verbal abstract reasoning. The left cingulum predicted processing speed. The right anterior AF predicted verbal abstract reasoning.

Conclusion

WM tract disruption predicts cognitive dysfunction in glioma patients. By improving knowledge of WM tract organization, this analysis may guide maximum surgical resection and functional preservation in glioma patients.

Executive functioning following surgery near the frontal aslant tract in low-grade glioma patients: A patient-specific tractography study

BACKGROUND

The Frontal Aslant Tract (FAT) has been associated with executive functions (EF), but it remains unclear what role the FAT plays in EF, and whether preoperative dysfunction of the FAT is associated to long-lasting postsurgical executive impairments.

METHODS

In this study, we examined the course of EF from pre-surgery (n = 75) to 3 (n = 61) and 12 (n = 25) months after surgery in patients with frontal and parietal low-grade gliomas (LGGs), to establish the degree to which long-term EF deficits exist. Secondly, we used patient-specific tractography to investigate the extent to which overlap of the tumor with the FAT, as well as integrity of the FAT, presurgery were related to EF on the short and longer term after surgery.

RESULTS

LGG patients performed worse than healthy controls on all EF tests before and 3 months postsurgery. Whereas performances on three out of the four tests had normalized 1 year postsurgery (n = 26), performance on the cognitive flexibility test remained significantly worse than in healthy controls. Patients in whom the tumor overlapped with the core of the right FAT performed worse presurgery on three of the EF tests compared to those in whom the tumor did not overlap with the right FAT. Presurgical right FAT integrity was not related to presurgical EF, but only to postsurgical EF (from pre-to 3 months postsurgery). Longitudinal analyses demonstrated that patients with right (but not left) FAT core overlap performed on average worse over the pre- and postsurgical timepoints on the cognitive flexibility test.

CONCLUSIONS

We emphasized that LGG patients perform worse than healthy controls on the EF tests, which normalizes 1-year postsurgery except for cognitive flexibility. Importantly, in patients with right hemispheric tumors, tumor involvement of the FAT was associated with worse pre- and 3- months postsurgical performance, specifically concerning cognitive flexibility.

Neuropsychological impairment in primary malignant brain tumor patients with awake craniotomy: a hospital-based registration study

PURPOSE

Neuroplasticity is an ability to maintain neural circuit function when facing damages. It is one of the reasons that making brain tumors notorious. Therefore, we evaluated the characteristics of patients with primary brain tumors, compared neuropsychological deficits between patients who had awake craniotomy with left- or right-sided tumors, and analyzed the association between white matter tracts and neuropsychological deficits in patients with right-sided tumors.

METHODS

Using the registration dataset of Chang Gung Memory Hospital between 2014 and 2020, this study included a total of 698 adult patients who received craniotomy for primary brain tumors (538 of conventional craniotomy; 160 of awake craniotomy). Neuropsychological assessments were arranged in patients as preoperative evaluation for awake craniotomies.

RESULTS

A lower proportion of right-sided tumors was noted in patient who had awake craniotomy than those who had conventional craniotomy (33.8% and 51.5%, p < 0.001). In awake craniotomy, 88.7% of patients with left-sided tumors and 77.8% of patients with right-sided tumors had neuropsychological impairment. Patients with left-sided tumors had worse preoperative performance compared to those with right-sided tumors in global function (36.2% and 8.0%, p < 0.001), language domain (57.6% and 22.2%, p < 0.001), and attention (36.0% and 18.5%, p = 0.02). Furthermore, in those with right-sided low-grade gliomas, patients involving pathway of superior longitudinal fasciculus (SLF) I had a higher risk of deficits than those without involvement in verbal memory (p = 0.001, Odd ratio = 11.2, 95% CI = 1.8 ~ 71.4) and visual memory (p = 0.048, Odd ratio = 10.5, 95% CI = 1.0 ~ 111).

CONCLUSION

In awake craniotomy, patients with left-sided brain tumors had worse cognitive function than those with right-sided tumors in terms of global function, language, and attention. 77% of patients with right-sided tumors had neuropsychological impairment. Therefore, a comprehensive neuropsychological evaluation and awake craniotomy are necessary for patients with brain tumors.

The longitudinal relation between executive functioning and multilayer network topology in glioma patients

Many patients with glioma, primary brain tumors, suffer from poorly understood executive functioning deficits before and/or after tumor resection. We aimed to test whether frontoparietal network centrality of multilayer networks, allowing for integration across multiple frequencies, relates to and predicts executive functioning in glioma. Patients with glioma (n = 37) underwent resting-state magnetoencephalography and neuropsychological tests assessing word fluency, inhibition, and set shifting before (T1) and one year after tumor resection (T2). We constructed binary multilayer networks comprising six layers, with each layer representing frequency-specific functional connectivity between source-localized time series of 78 cortical regions. Average frontoparietal network multilayer eigenvector centrality, a measure for network integration, was calculated at both time points. Regression analyses were used to investigate associations with executive functioning. At T1, lower multilayer integration (p = 0.017) and epilepsy (p = 0.006) associated with poorer set shifting (adj. R2 = 0.269). Decreasing multilayer integration (p = 0.022) and not undergoing chemotherapy at T2 (p = 0.004) related to deteriorating set shifting over time (adj. R2 = 0.283). No significant associations were found for word fluency or inhibition, nor did T1 multilayer integration predict changes in executive functioning. As expected, our results establish multilayer integration of the frontoparietal network as a cross-sectional and longitudinal correlate of executive functioning in glioma patients. However, multilayer integration did not predict postoperative changes in executive functioning, which together with the fact that this correlate is also found in health and other diseases, limits its specific clinical relevance in glioma.

Cognitive reserve and individual differences in brain tumour patients

The aim of the paper is to determine the effects of the cognitive reserve on brain tumour patients' cognitive functions and, specifically, if cognitive reserve helps patients cope with the negative effects of brain tumours on their cognitive functions. We retrospectively studied a large sample of around 700 patients, diagnosed with a brain tumour. Each received an MRI brain examination and performed a battery of tests measuring their cognitive abilities before they underwent neurosurgery. To account for the complexity of cognitive reserve, we construct our cognitive reserve proxy by combining three predictors of patients' cognitive performance, namely, patients' education, occupation, and the environment where they live. Our statistical analysis controls for the type, side, site, and size of the lesion, for fluid intelligence quotient, and for age and gender, in order to tease out the effect of cognitive reserve on each of these tests. Clinical neurological variables have the expected effects on cognitive functions. We find a robust positive effect of cognitive reserve on patients' cognitive performance. Moreover, we find that cognitive reserve modulates the effects of the volume of the lesion: the additional negative impact of an increase in the tumour size on patients' performance is less severe for patients with higher cognitive reserve. We also find substantial differences in these effects depending on the cerebral hemisphere where the lesion occurred and on the cognitive function considered. For several of these functions, the positive effect of cognitive reserve is stronger for patients with lesions in the left hemisphere than for patients whose lesions are in the right hemisphere. The development of prevention strategies and personalized rehabilitation interventions will benefit from our contribution to understanding the role of cognitive reserve, in addition to that of neurological variables, as one of the factors determining the patients' individual differences in cognitive performance caused by brain tumours.

Factors Associated With Neurocognitive Impairment Following Chemoradiotherapy in Patients With High-Grade Glioma: Results of a Prospective Trial

BACKGROUND

High-grade gliomas (HGG) are highly fatal tumors despite advanced multimodality management. They are also associated with neurocognitive impairment, both due to disease pathology and treatment. We aimed to assess various risk factors responsible for neurocognitive decline in HGG patients undergoing adjuvant chemoradiation.

METHODS

Newly diagnosed HGG patients who underwent maximal safe resection were included. Patients received volumetric modulated arc therapy to a dose of 60 Gy in 30 fractions, along with concurrent temozolomide (TMZ) at a dose of 75 mg/m²/day orally; thereafter adjuvant TMZ (150-200 mg/m² for 5 days), given every 28 days for 6 to 8 cycles. The Mini-Mental State Examination questionnaire was used to measure cognitive impairment of each study patient at various time points. Cox regression model was used for univariate and multivariable analysis of data to establish possible risk factors.

RESULTS

Fifty-three patients were enrolled and analyzed. At a median follow-up of 15 months, 30 patients (56.6%) developed cognitive impairment, and 23 patients (43.4%) did not. On univariate analysis, HGG with WHO grade 4, glioblastoma and diffuse midline glioma histology, IDH-wild type, recursive partitioning analysis class IV/V, and only biopsy of primary tumor were significantly associated with neurocognitive impairment, but none of them were independent risk factors on multivariable analysis. Planning target volume and dose received by ipsilateral hippocampus were also significantly correlated with cognitive decline in HGG patients.

CONCLUSION

Decline in neurocognitive functions in HGG patients is multifactorial and can be attributed to an amalgam of various tumor, patient, and treatment-related factors.

Baseline neurocognitive dysfunction is ubiquitous in intrinsic brain tumors- results from a large Indian cohort of patients and analysis of factors associated with domain-specific dysfunction

Background

Neurocognitive function (NCF) before surgery is an important marker of baseline performance in patients with brain tumors. Increasingly, neurocognitive deficits (NCD) have been demonstrated in a high proportion of patients. Selection bias (patient, tumor, and surgical procedure related) may influence the prevalence and type of domains involved in patients with gliomas.

Methods

We evaluated baseline NCF in a consecutive cohort of intra-axial tumors in Indian patients (n = 142). A comprehensive battery evaluating five domains - attention & executive function (EF), memory, language, visuospatial function and visuomotor abilities was used. Deficits were categorized as severe and mild-moderate. Factors associated with severe NCD were evaluated.

Results

Severe NCD was present in 90% of the patients, 70% of them having affection of at least 2 domains. Attention-EF, memory and visuomotor speed were most affected. 132 underwent surgery (69 awake, 63 under general anesthesia - GA). The awake cohort had younger patients with lower grade gliomas and more left sided tumors. Multi-domain dysfunction was seen almost equally in awake/GA groups as well as left/right sided tumors. On multivariate analysis, older age, lower educational status and larger tumor volume adversely affected NCF in many of the domains. Only language dysfunction was location specific (temporal lobe tumors) though not laterality (left/right) specific.

Conclusions

NCD were seen in a large majority of cases before surgery, including those undergoing awake surgery. Language may be affected even in tumors in the non-dominant hemisphere. Attention-EF and memory are most affected and need to be factored in while assessing patient performance intraoperatively during awake surgery as well as tailoring rehabilitative measures subsequently.

Rehabilitation interventions for glioma patients: a mini-review

Glioma is a group of tumors that originate from glial cells within the central nervous system and comprise 27% of all tumors and 80% of malignant tumors. With remarkable progress in surgical practices, chemotherapy, and radiation therapy, patients with glioma are experiencing greater survival times, which means they need more rehabilitative care. In fact, people with this condition may experience a variety of symptoms that can affect their functions and drastically reduce their quality of life. In fact, patients suffering from glioma has a distinctive symptom complex highlighting the requirement for customized care. Growing evidence shows that rehabilitation therapy can improve the functional prognosis and quality of life of glioma patients. However, there is limited evidence of the success of rehabilitation protocols designed specifically for individuals with glioma. It is essential to determine the most comprehensive rehabilitation programs as well as the sufficient resources, dosage, and duration. The goal of this mini-review was to classify and map rehabilitation interventions used to treat multiple disabling sequalae in individuals affected by glioma. We aim to provide a comprehensive overview of the rehabilitation protocols used for this population, so that clinicians have a guide to support treatment and an inspiration for further research. This document is intended to be a reference point for professionals involved in the management of adult patients with gliomas. Further exploration is needed to form improved care models for recognizing and addressing functional restrictions in this population.

Controllability and Robustness of Functional and Structural Connectomic Networks in Glioma Patients

Previous studies suggest that the topological properties of structural and functional neural networks in glioma patients are altered beyond the tumor location. These alterations are due to the dynamic interactions with large-scale neural circuits. Understanding and describing these interactions may be an important step towards deciphering glioma disease evolution. In this study, we analyze structural and functional brain networks in terms of determining the correlation between network robustness and topological features regarding the default-mode network (DMN), comparing prognostically differing patient groups to healthy controls. We determine the driver nodes of these networks, which are receptive to outside signals, and the critical nodes as the most important elements for controllability since their removal will dramatically affect network controllability. Our results suggest that network controllability and robustness of the DMN is decreased in glioma patients. We found losses of driver and critical nodes in patients, especially in the prognostically less favorable IDH wildtype (IDHwt) patients, which might reflect lesion-induced network disintegration. On the other hand, topological shifts of driver and critical nodes, and even increases in the number of critical nodes, were observed mainly in IDH mutated (IDHmut) patients, which might relate to varying degrees of network plasticity accompanying the chronic disease course in some of the patients, depending on tumor growth dynamics. We hereby implement a novel approach for further exploring disease evolution in brain cancer under the aspects of neural network controllability and robustness in glioma patients.

The impact of patient factors and tumor characteristics on language neuroplasticity in left hemispheric diffuse gliomas prior to surgical resection

PURPOSE

Language networks are reorganized during glioma growth, leading to varying language performance in patients with gliomas located in or around language-eloquent areas. Therefore, pre-treated language performance reflects the neuroplasticity potential. Different domains of language processing, such as speech expression, repetition, and comprehension, involving different neural networks. We analyzed the effects of patient factors and tumor characteristics on the pre-treated performance to investigate neuroplastic potential of different language domains.

METHODS

Patient age, sex, education level, tumor grade, language pathway involvement, T1 contrast enhanced (C+), and FLAIR (T2) volume were selected as variables. The correlation with abnormal language performance was verified using univariate and multivariate logistic regression.

RESULTS

In total, 104 left hemispheric glioma patients were enrolled in this study. 44% of patients had repetitive abnormalities, 34.9% had comprehensive abnormalities, and 32.1% had expressive abnormalities. The proportion of normal language performance was 60% in grade 2 and 3 gliomas and 16% in grade 4 gliomas. Tumor grade (p = 0.006) and T2 volume (p = 0.008) were associated with abnormal performance in the expressive domain, education level (p = 0.004) and T1 C+ volume (p = 0.049) in the repetitive domain, and education level (p = 0.013), T2 volume (p = 0.011), and tumor grade (p = 0.089) in the comprehensive domain.

CONCLUSION

Different clinical and radiological factors affected the abnormal performance of the three language domains, indicating their functional connectivity and neuroplastic potential are inherently varied. The dynamic interactions between patient factors, tumor characteristics, and language processing should be considered when resecting left hemispheric gliomas.

Health-related quality of life and cognitive failures in patients with lower-grade gliomas treated with radiotherapy

PURPOSE

Patients with lower grade (grade 2 and 3) glioma (LGG) frequently experience prolonged clinical course after multimodal therapy (including surgery, radiotherapy (RT), and chemotherapy). There is therefore significant concern about the potential long-term impact of the disease and treatments on quality of life (QOL) and cognitive functioning. In this context, we evaluated health related QOL and cognitive failures in LGG patients previously treated in our RT department.

PATIENTS AND METHODS

Adult LGG patients previously treated with RT were prospectively included. Patients were evaluated based on standardized questionnaires [i.e., EORTC QLQ-C30, EORTC QLQ-BN20, and cognitive failures questionnaire (CFQ)].

RESULTS

Forty-eight patients were included. Median time elapsed since the end of RT was 59.5 months (range: 4-297). Based on EORTC QLQ-C30 and QLQ-BN20, the most prevalent HRQOL issues were impaired cognitive functioning (50% of the patients), impaired emotional functioning (47.9%), financial difficulties (43.7%), fatigue (43.7%), future uncertainty (39.6%), and impaired physical functioning (35.4%). Based on the CFQ, 35.4% of the patients showed increased tendency to cognitive failures.

CONCLUSION

Patients with LGG frequently experience impairments in HRQOL and cognitive failures after treatment (including RT). Further efforts are therefore warranted to improve the QOL and cognitive outcome of these patients.

Remote assessment of cognition and quality of life following radiotherapy for nasopharyngeal carcinoma: deep-learning-based predictive models and MRI correlates

PURPOSE

Irradiation of the brain regions from nasopharyngeal carcinoma (NPC) radiotherapy (RT) is frequently unavoidable, which may result in radiation-induced cognitive deficit. Using deep learning (DL), the study aims to develop prediction models in predicting compromised cognition in patients following NPC RT using remote assessments and determine their relation to the quality of life (QoL) and MRI changes.

METHODS

Seventy patients (20-76 aged) with MRI imaging (pre- and post-RT (6 months-1 year)) and complete cognitive assessments were recruited. Hippocampus, temporal lobes (TLs), and cerebellum were delineated and dosimetry parameters were extracted. Assessments were given post-RT via telephone (Telephone Interview Cognitive Status (TICS), Telephone Montreal Cognitive Assessment (T-MoCA), Telephone Mini Addenbrooke's Cognitive Examination (Tele-MACE), and QLQ-H&N 43). Regression and deep neural network (DNN) models were used to predict post-RT cognition using anatomical and treatment dose features.

RESULTS

Remote cognitive assessments were inter-correlated (r > 0.9). TLs showed significance in pre- and post-RT volume differences and cognitive deficits, that are correlated with RT-associated volume atrophy and dose distribution. Good classification accuracy based on DNN area under receiver operating curve (AUROC) for cognitive prediction (T-MoCA AUROC = 0.878, TICS AUROC = 0.89, Tele-MACE AUROC = 0.919).

CONCLUSION

DL-based prediction models assessed using remote assessments can assist in predicting cognitive deficit following NPC RT. Comparable results of remote assessments in assessing cognition suggest its possibility in replacing standard assessments.

IMPLICATIONS FOR CANCER SURVIVORS

Application of prediction models in individual patient enables tailored interventions to be provided in managing cognitive changes following NPC RT.

Preservation of Neurocognition after Proton Beam Radiation Therapy for Intracranial Tumors: First Results from REGI-MA-002015

PURPOSE

Proton beam radiation therapy reduces dose to healthy brain tissue and thereby decreases the risk of treatment-related decline in neurocognition. Considering the paucity of prospective data, this study aimed to evaluate neurocognitive performance in an adult patient population with intracranial tumors.

METHODS AND MATERIALS

Between 2017 and 2021, patients enrolled in the MedAustron registry study and irradiated for intracranial tumors were eligible for neurocognitive assessment. Patients with available 1-year follow-up data were included in the analysis. The test battery consisted of a variety of standardized tests commonly used in European Organization for Research and Treatment of Cancer trials. Scores were transformed into z scores to account for demographic effects, and clinically relevant change was defined as a change of ≥1.5 standard deviations. Binary logistic regression analysis and the χ² test were conducted for clinical parameters and dosimetric hippocampal parameters to evaluate the relationship with overall cognitive decline and changes in memory.

RESULTS

One hundred twenty-three patients with mostly nonprogressive, extra-axial tumors and neurocognitive assessment at baseline and treatment end as well as 3, 6, and 12 months after completion of proton beam radiation therapy were analyzed. Overall, 7 test scores revealed stability in neurocognitive function with minimal positive changes 1 year after treatment completion (statistically significant in 6 of 7 tests), whereas the majority had no or minimal baseline deficits. At 1-year follow-up, 89.4% of all patients remained stable in their overall cognitive functioning without clinically relevant deterioration in 2 or more tests. None of them showed disease progression. Of the patients, 8.1% presented with radiation-induced brain lesions and exhibited a higher percentage of overall cognitive deterioration without reaching statistical significance. Multivariate binary logistic regression analysis revealed higher age at baseline as the only independent parameter to be associated with an overall clinically relevant cognitive decline. There was no significant correlation of hippocampal doses and memory functioning.

CONCLUSIONS

One year after proton therapy, we observed preservation of cognitive functioning in the vast majority of our patients with intracranial tumors.

A Systematic Review and Meta-Analysis of Supramarginal Resection versus Gross Total Resection in Glioblastoma: Can We Enhance Progression-Free Survival Time and Preserve Postoperative Safety?

To date, gross total resection (GTR) of the contrast-enhancing area of glioblastoma (GB) is the benchmark treatment regarding surgical therapy. However, GB infiltrates beyond those margins, and most tumors recur in close proximity to the initial resection margin. It is unclear whether a supramarginal resection (SMR) enhances progression-free survival (PFS) time without increasing the incidence of postoperative surgical complications. The aim of the present meta-analysis was to investigate SMR with regard to PFS and postoperative surgical complications. We searched for eligible studies comparing SMR techniques with conventional GTR in PubMed, Cochrane Library, Web of Science, and Medline databases. From 3158 initially identified records, 11 articles met the criteria and were included in our meta-analysis. Our results illustrate significantly prolonged PFS time in SMR compared with GTR (HR: 11.16; 95% CI: 3.07–40.52, p = 0.0002). The median PFS of the SMR arm was 8.44 months (95% CI: 5.18–11.70, p < 0.00001) longer than the GTR arm. The rate of postoperative surgical complications (meningitis, intracranial hemorrhage, and CSF leaks) did not differ between the SMR group and the GTR group. SMR resulted in longer median progression-free survival without a negative postoperative surgical risk profile. Multicentric prospective randomized trials with a standardized definition of SMR and analysis of neurologic functioning and health-related quality of life are justified and needed to improve the level of evidence.

Presurgical Executive Functioning in Low-Grade Glioma Patients Cannot Be Topographically Mapped

Executive dysfunctions have a high prevalence in low-grade glioma patients and may be the result of structural disconnections of particular subcortical tracts and/or networks. However, little research has focused on preoperative low-grade glioma patients. The frontotemporoparietal network has been closely linked to executive functions and is substantiated by the superior longitudinal fasciculus. The aim of this study was to investigate their role in executive functions in low-grade glioma patients. Patients from two neurological centers were included with IDH-mutated low-grade gliomas. The sets of preoperative predictors were (i) distance between the tumor and superior longitudinal fasciculus, (ii) structural integrity of the superior longitudinal fasciculus, (iii) overlap between tumor and cortical networks, and (iv) white matter disconnection of the same networks. Linear regression and random forest analyses were performed. The group of 156 patients demonstrated significantly lower performance than normative samples and had a higher prevalence of executive impairments. However, both regression and random forest analyses did not demonstrate significant results, meaning that neither structural, cortical network overlap, nor network disconnection predictors explained executive performance. Overall, our null results indicate that there is no straightforward topographical explanation of executive performance in low-grade glioma patients. We extensively discuss possible explanations, including plasticity-induced network-level equipotentiality. Finally, we stress the need for the development of novel methods to unveil the complex and interacting mechanisms that cause executive deficits in low-grade glioma patients.

The relationship between mental fatigue, cognitive functioning, and employment status in patients with low-grade glioma: a cross-sectional single-center study

PURPOSE

To evaluate fatigue and cognitive functioning in patients with low-grade glioma and to assess whether cognitive functioning and employment status differ between patients with severe and non-severe mental fatigue.

METHODS

Cross-sectional study. Fatigue was measured with the multidimensional fatigue inventory, objective cognitive functioning with a neuropsychological test battery, and mood with the Center for Epidemiological Studies Depression Scale.

RESULTS

Thirty-one patients, mean age 44 ± 11, mean time post-diagnosis 2.5 ± 1.4 years, participated. Severe mental fatigue was present in 55% and depression in 36% of the patients. Attention deficits were observed in 75% (Stroop's test), memory deficits in 36% (Rey Auditory Verbal Learning Test), and executive functioning deficits in 42% (Stroop's test). Severe mental fatigue patients demonstrated significantly worse scores on Stroop's test-Card-II (p = 0.043), Trail Making Test-B (p = 0.014), Trail Making Test-B/A (p = 0.014), and Digit-Span (p = 0.046), compared to non-severe mental fatigue patients. Severe mental fatigue patients worked significantly less hours per week (p = 0.013) and had more changes in their employment status (p = 0.009) after diagnosis.

CONCLUSIONS

Patients with low grade glioma show high rates of fatigue, especially in the mental domain, which might be associated with deficits in cognitive functioning and changes in employment status.Implications for rehabilitationThe majority of patients with low grade glioma suffers from severe mental fatigue and has deficits in cognitive functioning, which may affect employment status.Patients with low grade glioma should be screened for fatigue with the multidimensional fatigue inventory, to differentiate between mental and physical fatigue.Patients with low grade glioma with severe mental fatigue should be screened for problems in cognitive functioning with an objective neuropsychological test battery.Cognitive and vocational rehabilitation programs should aim at coping with severe mental fatigue and attention deficits in patients with low grade glioma.

Self-Referential Processing and Resting-State Functional MRI Connectivity of Cortical Midline Structures in Glioma Patients

Metacognition has only scarcely been investigated in brain tumor patients. It is unclear if and how the tumor-lesioned brain might be able to maintain an adequate sense-of-self. As cortical midline structures (CMS) are regarded as essential for self-referential mental activity, we investigated resting-state fMRI connectivity (FC) of CMS to the default-mode network (DMN) and to the whole brain, comparing glioma patients and matched controls. Subjects furthermore performed a trait judgement (TJ), a trait recall task (TR), and neuropsychological testing. In the TJ, adjectives had to be ascribed as self- or non-self-describing, assessing the self-serving effect (SSE), a normally observed bias for positive traits. In the TR, the mnemic neglect effect (MNE), a memory advantage for positive traits, was tested. The groups were compared and partial correlations between FC and test metrics were analyzed. Although patients were significantly impaired in terms of verbal memory, groups did not differ in the SSE or the MNE results, showing preserved metacognitive abilities in patients. FC of CMS to the DMN was maintained, but was significantly decreased to whole brain in the patients. FC of the dorsomedial prefrontal cortex (DMPFC) to whole brain was correlated with the MNE in patients. Preserving the DMPFC in therapeutic interventions might be relevant for maintaining self-related verbal information processing in the memory domain in glioma patients.

The need to consider return to work as a main outcome in patients undergoing surgery for diffuse low-grade glioma: a systematic review

OBJECTIVE

For a long time, return to work (RTW) has been neglected in patients harboring a diffuse low-grade glioma (LGG). However, a majority of LGG patients worked at time of diagnosis. Moreover, these patients now live longer given current treatment paradigms, especially thanks to early maximal surgery.

METHODS

We systematically searched available medical databases for studies that reported data on RTW in patients who underwent resection for LGG.

RESULTS

A total of 30 studies were selected: 19 considered RTW (especially rate and timing) as an outcome and 11 used scales of health-related quality of life (HRQoL) which included work-related aspects. Series that considered RTW as a main endpoint were composed of 1014 patients, with postoperative RTW rates ranging from 31 to 97.1% (mean 73.1%). Timing to RTW ranged from 15 days to 22 months (mean 6.3 months). Factors related to an increased proportion of RTW were: younger age, better neurologic status, having a white-collar occupation, working pre-operatively, being the sole breadwinner, the use of awake surgery, and greater extent of resection. Female sex, older age, poor neurologic status, pre-operative history of work absences, slow lexical access speed, and postoperative seizures were negatively related to RTW. No studies that used HRQoL scales directly investigated RTW rate or timing.

CONCLUSIONS

RTW was scarcely analyzed in LGG patients who underwent resection. However, because they are usually young, with no or only mild functional deficits and have a longer life expectancy, postoperative RTW should be assessed more systematically and accurately as a main outcome. As majority (61.5-100%) of LGG patients were working at time of surgery, the responsibility of neurosurgeons is to bring these patients back to their previous activities according to his/her wishes. RTW might also be included as a critical endpoint for future prospective studies and randomized control trials on LGGs.

Long-Term Outcomes of Patients with Primary Brain Tumors after Acute Rehabilitation: A Retrospective Analyses of Factors

Although primary brain tumors are relatively rare, they cause significant morbidity and mortality due to the high rates of neurological impairment. The purpose of this study was to examine the physical and functional outcomes of patients with primary brain tumors who had undergone inpatient rehabilitation. This was a retrospective study which recruited 163 patients who had been admitted for inpatient rehabilitation. Rehabilitation outcomes, including the Functional Independence Measure (FIM) and Glasgow Outcome Scale (GOS), were recorded up to 1 year post-discharge. The majority of patients (79.1%) had low-grade (WHO Class I-II) tumors, 35 (21.5%) were diagnosed with GBM and 52 (31.9%) had recurrent brain tumors. Rehabilitation outcomes were sustained, with 125 (76.7%) and 113 (69.3%) patients having a GOS of ≥4 at 6 months and 1 year after discharge, respectively. A GOS of ≥4 at 1 year was negatively associated with high-grade tumors (p < 0.001) and radiotherapy (p = 0.028), and positively associated with a higher discharge FIM motor score (p < 0.001) and the presence of a caregiver after discharge (p = 0.034). Our study demonstrates significant positive functional benefits from 4 weeks of inpatient neuro-oncological rehabilitation for patients with primary brain tumors, as well as the importance of supportive care from caregivers.

Influences on cognitive outcomes in adult patients with gliomas: A systematic review

People with brain tumors, including those previously treated, are commonly affected by a range of neurocognitive impairments involving executive function, memory, attention, and social/emotional functioning. Several factors are postulated to underlie this relationship, but evidence relating to many of these factors is conflicting and does not fully explain the variation in cognitive outcomes seen in the literature and in clinical practice. To address this, we performed a systematic literature review to identify and describe the range of factors that can influence cognitive outcomes in adult patients with gliomas. A literature search was performed of Ovid MEDLINE, PsychINFO, and PsycTESTS from commencement until September 2021. Of 9,998 articles identified through the search strategy, and an additional 39 articles identified through other sources, 142 were included in our review. The results confirmed that multiple factors influence cognitive outcomes in patients with gliomas. The effects of tumor characteristics (including location) and treatments administered are some of the most studied variables but the evidence for these is conflicting, which may be the result of methodological and study population differences. Tumor location and laterality overall appear to influence cognitive outcomes, and detection of such an effect is contingent upon administration of appropriate cognitive tests. Surgery appears to have an overall initial deleterious effect on cognition with a recovery in most cases over several months. A large body of evidence supports the adverse effects of radiotherapy on cognition, but the role of chemotherapy is less clear. To contrast, baseline cognitive status appears to be a consistent factor that influences cognitive outcomes, with worse baseline cognition at diagnosis/pre-treatment correlated with worse long-term outcomes. Similarly, much evidence indicates that anti-epileptic drugs have a negative effect on cognition and genetics also appear to have a role. Evidence regarding the effect of age on cognitive outcomes in glioma patients is conflicting, and there is insufficient evidence for gender and fatigue. Cognitive reserve, brain reserve, socioeconomic status, and several other variables discussed in this review, and their influence on cognition and recovery, have not been well-studied in the context of gliomas and are areas for focus in future research.

Surveillance of long-term complications after treatment of adult brain tumor survivors—review and evidence-based recommendations

AbstractAs a result of treatment and diagnosis, adults with primary or metastatic brain tumors experience comorbidities that impacts their health and well-being. The Children’s Oncology Group has guideline recommendations for childhood survivors of brain tumors; however, guidelines for monitoring long-term sequela among adult brain tumor survivors are lacking. The purpose of this review is to present the screening recommendations for the long-term complications after brain tumor treatment from a multidisciplinary panel of healthcare professionals. Chronic complications identified include cognitive dysfunction, vasculopathy, endocrinopathy, ophthalmic, ototoxicity, physical disability, sleep disturbance, mood disorder, unemployment, financial toxicity, and secondary malignancy. We invited specialists across disciplines to perform a literature search and provide expert recommendations for surveillance for long-term complications for adult brain tumor survivors. The Brain Tumor Center Survivorship Committee recommends routine screening using laboratory testing, subjective assessment of symptoms, and objective evaluations to appropriately monitor the complications of brain tumor treatments. Effective monitoring and treatment should involve collaboration with primary care providers and may require referral to other specialties and support services to provide patient-centered care during neuro-oncology survivorship. Further research is necessary to document the incidence and prevalence of medical complications as well as evaluate the efficacy of screening and neuro-oncology survivorship programs.

Constant Multi-Tasking With Time Constraint to Preserve Across-Network Dynamics Throughout Awake Surgery for Low-Grade Glioma: A Necessary Step to Enable Patients Resuming an Active Life

Awake surgery for brain gliomas improves resection while minimizing morbidity. Although intraoperative mapping was originally used to preserve motor and language functions, the considerable increase of life expectancy, especially in low-grade glioma, resulted in the need to enhance patients’ long-term quality of life. If the main goal of awake surgery is to resume normal familial and socio-professional activities, preventing hemiparesis and aphasia is not sufficient: cognitive and emotional functions must be considered. To monitor higher-order functions, e.g., executive control, semantics or mentalizing, further tasks were implemented into the operating theater. Beyond this more accurate investigation of function-specific neural networks, a better exploration of the inter-system communication is required. Advances in brain connectomics led to a meta-network perspective of neural processing, which emphasizes the pivotal role of the dynamic interplay between functional circuits to allow complex and flexible, goal-directed behaviors. Constant multi-tasking with time constraint in awake patients may be proposed during intraoperative mapping, since it provides a mirror of the (dys)synchronization within and across neural networks and it improves the sensitivity of behavioral monitoring by increasing cognitive demand throughout the resection. Electrical mapping may hamper the patient to perform several tasks simultaneously whereas he/she is still capable to achieve each task in isolation. Unveiling the meta-network organization during awake mapping by using a more ecological multi-demand testing, more representative of the real-life conditions, constitutes a reliable way to tailor the surgical onco-functional balance based upon the expectations of each patient, enabling him/her to resume an active life with long-lasting projects.

Patient-reported cognitive function before and after glioma surgery

Background

Little is known about the extent to which glioma patients experience subjective changes in cognitive function following surgery. We sought to assess patient-reported cognitive function before and after glioma surgery and explore potential factors associated with cognitive change.

Methods

In a prospective population-based study, patient-reported cognitive function was measured in 182 patients undergoing primary surgery for diffuse glioma (141 high-grade gliomas (HGG) and 41 low-grade gliomas (LGG)) by using the European Organisation for Research and Treatment of Cancer (EORTC) QLQ-C30 cognitive function subscale preoperatively and at 1 and 6 months postoperatively. Binomial logistic regression models were used to assess factors possibly associated with patient-reported cognitive changes.

Results

In the HGG group, the mean cognitive function score increased from 70.9 (95% 66.6, 75.2) preoperatively to 85.1 (95% CI 81.2, 89.0) (p < 0.001) and 83.3 (95% CI 79.1, 87.6) (p < 0.001) at 1 and 6 months postoperatively, respectively. In the LGG group, the mean score was 80.9 (95% CI 74.4, 87.4) preoperatively and remained stable at postoperative follow-ups. Females reported lower scores than males. At an individual level, both improvement and deterioration in cognitive scores were frequently seen in LGG and HGG patients after surgery. Preoperative use of corticosteroids and large tumor volume were predictors for cognitive improvement at 1 month postoperatively. No predictors were identified for cognitive improvement at 6 months and worsening at 1 and 6 months.

Conclusion

Many glioma patients experience perioperative subjective changes in cognitive function after surgery. At group level, HGG patients reported improved cognitive function after surgery, while LGG patients reported stable cognitive function. Preoperative use of corticosteroids and large tumor volume were independently associated with postoperative improvement.

Daily functioning in glioma survivors: associations with cognitive function, psychological factors and quality of life

Aim: Understanding and supporting quality of life (QoL) and daily functioning in glioma patients is a clinical imperative. In this study, we examined the relationship between cognition, psychological factors, measures of health-related QoL and functioning in glioma survivors. Materials & methods: We examined neuropsychological, self-reported cognition, mood and QoL correlates of work and non-work-related daily functioning in 23 glioma survivors, and carried out linear models of the best predictors. Results & conclusion: A total of 13/23 participants were working at the time of enrollment. The best model for worse work-related functioning (R2 = .83) included worse self-reported cognitive function, depression, loneliness and brain tumor symptoms. The best model for worse non-work-related functioning (R2 = .61) included worse self-reported cognitive functioning, anxiety, sleep disturbance and physical functioning. Neuropsychological variables were not among the most highly correlated with function. Worse cognitive, particularly self-reported and psychosocial outcomes may compromise optimal functioning in glioma survivors.

The Montreal Cognitive Assessment (MoCA) in Neuro-Oncology: A Pilot Study of Feasibility and Utility in Telehealth and In-Person Clinical Assessments

Background

Cognitive impairments are a common burden for patients with primary CNS tumors. Neuropsychological assessment batteries can be too lengthy, which limits their use as an objective measure of cognition during routine care. The purpose of this study was to evaluate the feasibility and utility of the brief Montreal Cognitive Assessment (MoCA) in routine in-person and telehealth visits (as a result of the global COVID-19 pandemic) with neuro-oncology patients.

Methods

71 adults with primary CNS tumors completed MoCA testing in-person (n=47) and via telehealth (n=24). Patient-reported outcomes (PROs), including symptom burden and interference, perceived cognition, general health status, and anxiety and depression, were and correlation analysis were included in this study. Feasibility was assessed through a provider satisfaction questionnaire.

Results

Patients were primarily White (83%), college-educated (71%) males (54%) with high grade tumors (66%). The average total score on the MoCA administered in-person was 25 (range: 6-30), with 34% classified as abnormal, and the average total score via telehealth was 26 (range: 12-30), with 29% classified as abnormal. Providers reported satisfaction in using the MoCA during routine clinical care, both in-person and via telehealth. Lower MoCA scores correlated with worse symptom severity, KPS, age, education, and previous treatment.

Conclusions

The MoCA was feasible in clinical and telehealth settings, and its relationship to clinical characteristics and PROs highlight the need for both objective and patient-reported measures of cognition to understand the overall cognitive profile of a patient with a CNS tumor.

Presurgical cognitive status in patients with low-grade glioma and epilepsy: Testing the effects of seizures, antiseizure medications, and tumor localization

BACKGROUND

Low-grade gliomas (LGGs) are frequently associated with epilepsy. There are few studies addressing the impact of seizures, antiseizure medications (ASMs), and lesion localization on presurgery cognitive functioning.

METHODS

We tested the relation between the above-mentioned variables in a continuous series of 73 young patients (mean age 38.3 years ± 11.7) affected by LGGs and epilepsy. The anatomical areas, involved in this sample, were the left insula with surrounding cortical and subcortical areas, the right precentral gyrus/rolandic operculum, and the white matter and cortical regions beneath.

RESULTS

Patients' presurgery cognitive status was within the normal range, with borderline performance for some tasks. We tested whether lower scores were related with lesion or with epilepsy-related factors. Multiple regression identified variables that predict test scores. The Token test score was predicted by a model (p = .0078) containing the DT2T1 MRI, corrected for seizure features. Object naming performance was predicted by a model (p = .0113) containing the localization, the DT2T1 MRI, corrected for sex, EEG, and onset. Verbal fluency score was predicted by a model (p = .0056) containing the localization and the DT2T1 MRI, corrected for AEDs and EEG. Working memory score was predicted by a model (p = .0117) containing Engel class, the DT2T1 MRI, corrected for sex. Clock drawing score was predicted by a model (p < .0001) containing the Engel class, AEDs, and EEG. TMT A score was predicted by a model (p = .0022) containing localization, corrected for EEG. TMT B-A score was predicted by a model (p = .0373) containing localization. Voxel Lesion Symptom Mapping analyses carried out on patients' lesion volumes confirmed that patients' level of performance correlated with lesion-related variables.

CONCLUSION

This preliminary study indicates that the presurgical level of performance for language tasks and for cognitive flexibility and shifting is mainly predicted by lesion-related variables, working memory by both lesion and epilepsy-related variables. Epilepsy clinical and instrumental characteristics predicted performance for visuospatial planning.

Longitudinal assessment of network reorganizations and language recovery in postoperative patients with glioma

For patients with glioma located in or adjacent to the linguistic eloquent cortex, awake surgery with an emphasis on the preservation of language function is preferred. However, the brain network basis of postoperative linguistic functional outcomes remains largely unknown. In this work, 34 patients with left cerebral gliomas who underwent awake surgery were assessed for language function and resting-state network properties before and after surgery. We found that there were 28 patients whose language function returned to at least 80% of the baseline scores within 3 months after surgery or to 85% within 6 months after surgery. For these patients, the spontaneous recovery of language function synchronized with changes within the language and cognitive control networks, but not with other networks. Specifically, compared with baseline values, language functions and global network properties were the worst within 1 month after surgery and gradually recovered within 6 months after surgery. The recovery of connections was tumour location dependent and was attributed to both ipsihemispheric and interhemispheric connections. In contrast, for six patients whose language function did not recover well, severe network disruptions were observed before surgery and persisted into the chronic phase. This study suggests the synchronization of functional network normalization and spontaneous language recovery in postoperative patients with glioma.

Complications, compliance and undertreatment do not explain the relationship between cognition and survival in diffuse glioma patients

Background

Cognitive deficits occur in all different grades of glioma. In a recent study, we found these deficits to be independently, and possibly causally, related to survival in diffuse gliomas. In this study, we investigated whether the relationship between cognition and survival was mediated by three different factors: undertreatment, complications of treatment, and compliance. We hypothesized that patients with cognitive impairment may undergo less intensive treatment, be less compliant, and suffer more from complications, resulting in shortened survival for cognitively impaired patients.

Methods

In a retrospective cohort study of patients undergoing awake craniotomy between operative neuropsychological assessments in five cognitive domains. We used Structural Equation Modeling to perform mediation analyses. Mediation analyses are analyses to evaluate whether a variable is a factor in the causal chain, referred to as an intermediate factor.

Results

In total 254 patients were included, of whom 111 patients were LGG patients and 143 were HGG patients. The most frequently impaired domain was memory (37.8% ≤–2 SD) in HGG and attention and executive functioning in LGG (33.3≤–1.5 SD). We confirmed the significant association between different cognitive domains and survival. These associations could not be explained by one of the aforementioned intermediate factors.

Conclusions

This suggests that other mechanisms should be involved in the relation between cognition and survival. Hypothetically, cognitive functioning can act as a marker for diffuse infiltration of the tumor or cognitive functioning and survival could be determined by overlapping germline and somatic tumoral molecular-genetic factors.

Distinct Slow-Wave Activity Patterns in Resting-State Electroencephalography and Their Relation to Language Functioning in Low-Grade Glioma and Meningioma Patients

Introduction

Brain tumours frequently cause language impairments and are also likely to co-occur with localised abnormal slow-wave brain activity. However, it is unclear whether this applies specifically to low-grade brain tumours. We investigate slow-wave activity in resting-state electroencephalography (EEG) in low-grade glioma and meningioma patients, and its relation to pre- and postoperative language functioning.

Method

Patients with a glioma (N = 15) infiltrating the language-dominant hemisphere and patients with a meningioma (N = 10) with mass effect on this hemisphere underwent extensive language testing before and 1 year after surgery. EEG was registered preoperatively, postoperatively (glioma patients only), and once in healthy individuals. Slow-wave activity in delta- and theta- frequency bands was evaluated visually and quantitatively by spectral power at three levels over the scalp: the whole brain, the affected hemisphere, and the affected region.

Results

Glioma patients had increased delta activity (affected area) and increased theta activity (all levels) before and after surgery. In these patients, increased preoperative theta activity was related to the presence of language impairment, especially to poor word retrieval and grammatical performance. Preoperative slow-wave activity was also related to postoperative language outcomes. Meningioma patients showed no significant increase in EEG slow-wave activity compared to healthy individuals, but they presented with word retrieval, grammatical, and writing problems preoperatively, as well as with writing impairments postoperatively.

Discussion

Although the brain-tumour pathology in low-grade gliomas and meningiomas has a different effect on resting-state brain activity, patients with low-grade gliomas and meningiomas both suffer from language impairments. Increased theta activity in glioma patients can be considered as a language-impairment marker, with prognostic value for language outcome after surgery.

Corticosteroids use and neurocognitive functioning in patients with recurrent glioblastoma: evidence from European Organization for Research and Treatment of Cancer (EORTC) trial 26101

Background

In patients with recurrent glioblastoma, corticosteroids are frequently used to mitigate intracranial pressure and to improve patient neurological functioning. To date, in these patients, no systematic studies have been performed to assess neurocognitive functioning (NCF) in relation to corticosteroid treatment.

Methods

Using baseline data (ie, prior to randomization) of European Organization for Research and Treatment of Cancer (EORTC) trial 26101, we performed regression analysis to assess the predictive value of corticosteroid intake on performance of the EORTC brain tumor clinical trial NCF test battery. The battery is comprised of the Hopkins Verbal Learning Test—Revised (HVLT-R), Controlled Oral Word Association Test (COWA), and Trail Making Test (A and B).

Results

Out of 321 patients, 148 (46.1%) were not using corticosteroids, and 173 were using dexamethasone (34.3%), methylprednisolone (9.7%), or other corticosteroids (9.9%). Patients on corticosteroids had worse performance on all neurocognitive tests. Regression analyses demonstrated a negative association between corticosteroids use and the HVLT-R free recall score (R² change = 0.034, F change (1, 272) = 13.392, P < .001) and HVLT-R Delayed Recall score (R² change = 0.028, F change (1, 270) = 10.623, P = .002). No statistically significant association was found for HVLT-R Delayed recognition, COWA, TMT part A and TMT part B (P > .05).

Conclusions

Glioblastoma patients prescribed with corticosteroids show poorer memory functions, expressive language, visual-motor scanning speed, and executive functioning than patients not using corticosteroids. Furthermore, we found a negative association between corticosteroid intake and memory functions. The possibility of deleterious effects of corticosteroids on NCF should be considered during clinical decision making.

Pretreatment patient-reported cognitive function in patients with diffuse glioma

Purpose

Cognitive function is frequently assessed with objective neuropsychological tests, but patient-reported cognitive function is less explored. We aimed to investigate the preoperative prevalence of patient-reported cognitive impairment in patients with diffuse glioma compared to a matched reference group and explore associated factors.

Methods

We included 237 patients with diffuse glioma and 474 age- and gender-matched controls from the general population. Patient-reported cognitive function was measured using the cognitive function subscale in the European Organisation for Research and Treatment of Cancer QLQ-C30 questionnaire. The transformed scale score (0–100) was dichotomized, with a score of ≤ 75 indicating clinically important patient-reported cognitive impairment. Factors associated with preoperative patient-reported cognitive impairment were explored in a multivariable regression analysis.

Results

Cognitive impairment was reported by 49.8% of the diffuse glioma patients and by 23.4% in the age- and gender-matched reference group (p < 0.001). Patients with diffuse glioma had 3.2 times higher odds (95% CI 2.29, 4.58, p < 0.001) for patient-reported cognitive impairment compared to the matched reference group. In the multivariable analysis, large tumor volume, left tumor lateralization, and low Karnofsky Performance Status score were found to be independent predictors for preoperative patient-reported cognitive impairment.

Conclusions

Our findings demonstrate that patient-reported cognitive impairment is a common symptom in patients with diffuse glioma pretreatment, especially in patients with large tumor volumes, left tumor lateralization, and low functional levels. Patient-reported cognitive function may provide important information about patients’ subjective cognitive health and disease status and may serve as a complement to or as a screening variable for subsequent objective testing.

Tumor-related molecular determinants of neurocognitive deficits in patients with diffuse glioma

BACKGROUND

Cognitive impairment is a common and debilitating symptom in patients with diffuse glioma, and is the result of multiple factors. We hypothesized that molecular tumor characteristics influence neurocognitive functioning (NCF), and aimed to identify tumor-related markers of NCF in diffuse glioma patients.

METHODS

We examined the relation between cognitive performance (executive function, memory, and psychomotor speed) and intratumoral expression levels of molecular markers in treatment-naive patients with diffuse glioma. We performed a single-center study in a consecutive cohort, through a two-step design: (1) hypothesis-free differential expression and gene set enrichment analysis to identify candidate oncogenetic markers for cognitive impairment. Nineteen molecular markers of interest were derived from this set of genes, as well as from prior knowledge; (2) correlation of cognitive performance to intratumoral expression levels of these nineteen molecular markers, measured with immunohistochemistry.

RESULTS

From 708 included patients with immunohistochemical data, we performed an in-depth analysis of neuropsychological data in 197, and differential expression analysis in 65 patients. After correcting for tumor volume and location, we found significant associations between expression levels of CD3 and IDH-1 and psychomotor speed; between IDH-1, ATRX, NLGN3, BDNF, CK2Beta, EAAT1, GAT-3, SRF, and memory performance; and between IDH-1, P-STAT5b, NLGN3, CK2Beta, and executive functioning. P-STAT5b, CD163, CD3, and Semaphorin-3A were independently associated after further correction for histopathological grade.

CONCLUSION

Molecular characteristics of glioma can be independent determinants of patients' cognitive functioning. This suggests that besides tumor volume, location, and histological grade, variations in glioma biology influence cognitive performance through mechanisms that include perturbation of neuronal communication. These results pave the way towards targeted cognition improving therapies in neuro-oncology.

T2 FLAIR Hyperintensity Volume Is Associated With Cognitive Function and Quality of Life in Clinically Stable Patients With Lower Grade Gliomas

Survival outcomes for patients with lower grade gliomas (LrGG) continue to improve. However, damage caused both by tumor growth and by the consequences of treatment often leads to significantly impaired cognitive function and quality of life (QoL). While neuropsychological testing is not routine, serial clinical MRIs are standard of care for patients with LrGG. Thus, having a greater understanding of MRI indicators of cognitive and QoL impairment risk could be beneficial to patients and clinicians. In this work we sought to test the hypothesis that in clinically stable LrGG patients, T2 FLAIR hyperintensity volumes at the time of cognitive assessment are associated with impairments of cognitive function and QoL and could be used to help identify patients for cognitive and QoL assessments and interventions. We performed anatomical MR imaging, cognitive testing and QoL assessments cross-sectionally in 30 clinically stable grade 2 and 3 glioma patients with subjective cognitive concerns who were 6 or more months post-treatment. Larger post-surgical T2 FLAIR volume at testing was significantly associated with lower cognitive performance, while pre-surgical tumor volume was not. Older patients had lower cognitive performance than younger patients, even after accounting for normal age-related declines in performance. Patients with Astrocytoma, IDH mutant LrGGs were more likely to show lower cognitive performance than patients with Oligodendroglioma, IDH mutant 1p19q co-deleted LrGGs. Previous treatment with combined radiation and chemotherapy was associated with poorer self-reported QoL, including self-reported cognitive function. This study demonstrates the importance of appreciating that LrGG patients may experience impairments in cognitive function and QoL over their disease course, including during periods of otherwise sustained clinical stability. Imaging factors can be helpful in identifying vulnerable patients who would benefit from cognitive assessment and rehabilitation.

Surgery vs. Biopsy in the Treatment of Butterfly Glioblastoma: A Systematic Review and Meta-Analysis

Simple Summary

There is uncertainty regarding the role of surgical resection in the management of butterfly glioblastoma (bGBM). We therefore investigated this question by pooling available data from the literature and performing a systematic review and meta-analysis. Our results show that operative management of bGBM was associated with longer overall survival compared with biopsy alone. This effect persisted in both >80% and <80% extent of resection subgroups. At the same time, complications were not statistically significantly higher; however, these were numerically larger for surgery. Our study corroborates findings from smaller studies and supports the consideration of surgery in the treatment of bGBM patients.

Abstract

Butterfly glioblastomas (bGBM) are grade IV gliomas that spread to bilateral hemispheres by infiltrating the corpus callosum. Data on the effect of surgery are limited to small case series. The aim of this meta-analysis was to compare resection vs. biopsy in terms of survival outcomes and postoperative complications. A systematic review of the literature was conducted using PubMed, EMBASE, and Cochrane databases through March 2021 in accordance with the PRISMA checklist. Pooled hazard ratios were calculated and meta-analyzed in a random-effects model including assessment of heterogeneity. Out of 3367 articles, seven studies were included with 293 patients. Surgical resection was significantly associated with longer overall survival (HR 0.39, 95%CI 0.2–0.55) than biopsy. Low heterogeneity was observed (I²: 0%). In further analysis, the effect persisted in extent of resection subgroups of both ≥80% and <80%. No statistically significant difference between surgery and biopsy was detected in terms of postoperative complications, although these were numerically larger for surgery. In patients with bGBM, surgical resection was associated with longer survival prospects compared with biopsy.