Rodent models of tumours of the central nervous system

Modelling of human diseases is an essential component of biomedical research, to understand their pathogenesis and ultimately, develop therapeutic approaches. Here, we will describe models of tumours of the central nervous system, with focus on intrinsic CNS tumours. Model systems for brain tumours were established as early as the 1920s, using chemical carcinogenesis, and a systematic analysis of different carcinogens, with a more refined histological analysis followed in the 1950s and 1960s. Alternative approaches at the time used retroviral carcinogenesis, allowing a more topical, organ-centred delivery. Most of the neoplasms arising from this approach were high-grade gliomas. Whilst these experimental approaches did not directly demonstrate a cell of origin, the localisation and growth pattern of the tumours already pointed to an origin in the neurogenic zones of the brain. In the 1980s, expression of oncogenes in transgenic models allowed a more targeted approach by expressing the transgene under tissue-specific promoters, whilst the constitutive inactivation of tumour suppressor genes ('knock out')-often resulted in embryonic lethality. This limitation was elegantly solved by engineering the Cre-lox system, allowing for a promoter-specific, and often also time-controlled gene inactivation. More recently, the use of the CRISPR Cas9 technology has significantly increased experimental flexibility of gene expression or gene inactivation and thus added increased value of rodent models for the study of pathogenesis and establishing preclinical models.

Increased Distress in Neurooncological Patients, a Monocentric Longitudinal Study: When to Screen Which Patient?

OBJECTIVE

Neurooncological patients are well-known to experience an increased psycho-oncological burden with a negative impact on distress, therapy adherence, quality of life, and finally survival. But still, psycho-oncological screening and support is rare, with ongoing discussion about specific screening time points and impact factors. Therefore, we analysed the psycho-oncologic treatment demand at specific disease-related time points throughout therapy.

METHODS

In this longitudinal, prospective, single-centre study, patients with malignant brain tumours were screened for increased distress (using the Distress Thermometer), anxiety, depression (Hospital Anxiety and Depression Scale questionnaire), and health-related quality of life interference (EORTC QLQ C30-BN20 questionnaire) at specific longitudinal time points during therapy. The results were correlated with sociodemographic and clinical data.

RESULTS

From 2013 to 2017, 2500 prospective screening data points from 512 malignant brain tumour patients were analysed. DT was identified as a significant predictor for psycho-oncological treatment demand (p < 0.001). Particularly significant time points concerning psycho-oncological burden were primary diagnosis and tumour recurrence. Next to these known factors, here, patients < 65 years old and female patients (p = 0.018 and p = 0.017) reflected increased screening results, whereas partnership and professional activity (p = 0.043; p = 0.017) were identified as contributing factors to a significantly decreased treatment demand.

CONCLUSIONS

The increased need for psycho-oncological support for neurooncological patients is underlined. Psycho-oncological support should particularly be offered at the time points of primary diagnosis and tumour recurrence. To support the positive effect of caregivers, they should be involved at an early stage.

Experiences of families post treatment for childhood brain tumours during medical clinic consultations regarding health-related quality of life, unmet needs and communication barriers: A qualitative exploration

BACKGROUND

Many studies highlight poor health-related quality of life (HRQoL) in children treated for brain tumours and their parents. However, little is known about the extent to which their informational, healthcare and communication needs regarding HRQoL are met during medical outpatient consultations.

AIM

To explore the experiences of families regarding communication with physicians about HRQoL issues during consultations after treatment for childhood brain tumours.

METHODS

Interviews were conducted with 18 families of children and adolescents aged 8-17 years after completion of brain tumour treatment. Participants had completed treatment within the last 5 years and were receiving regular outpatient follow-up care. Thematic analysis was undertaken using the Framework Method.

RESULTS

Five main themes were identified: (i) unmet emotional and mental health needs; (ii) double protection; (iii) unmet information needs; (iv) communication barriers within consultations; and (v) finding a new normal.

CONCLUSION

There was a need to improve communication between clinicians and these families, improve information provision, and overcome barriers to conversing with children within these outpatient consultations. Children and their parents should be supported to voice their current needs and concerns regarding their HRQoL. These findings will inform further development of the UK version of the 'KLIK' patient- and parent-reported outcome (PROM) portal.

Molecular and Pathological Features of Paediatric High-Grade Gliomas

Paediatric high-grade gliomas are among the most common malignancies found in children. Despite morphological similarities to their adult counterparts, there are profound biological and molecular differences. Furthermore, and thanks to molecular biology, the diagnostic pathology of paediatric high-grade gliomas has experimented a dramatic shift towards molecular classification, with important prognostic implications, as is appropriately reflected in both the current WHO Classification of Tumours of the Central Nervous System and the WHO Classification of Paediatric Tumours. Emphasis is placed on histone 3, IDH1, and IDH2 alterations, and on Receptor of Tyrosine Kinase fusions. In this review we present the current diagnostic categories from the diagnostic pathology perspective including molecular features.

A Case Report on a Common Tumour With an Uncommon Presentation: Glioblastoma

The most common type of primary brain tumour in adults is gliomas although rare. Glioblastomas are a subtype of gliomas with the worst prognosis having the ability to rapidly increase in size, even doubling within days to weeks. Patients can present with varied presentations depending on the site of the involvement, thus misleading in diagnosis due to vagueness. The most common clinical presentations include headaches, seizures, and focal neurological signs. However, there can be atypical presentations like personality changes and back pain due to meningeal irritation which may be the only presenting complaint in the early stages. Magnetic resonance imaging (MRI) is usually considered the only investigation required for the diagnosis of the illness. However, it can mislead in the early stages. Therefore, brain biopsy remains the gold standard in the diagnosis of glioblastoma multiforme. It is important to identify the subtype to decide on the prognosis and plan the management thereafter. Here, we present a 49-year-old woman with prominent personality changes, depressive symptoms, and atypical brain imaging findings. The definitive diagnosis was made with the brain biopsy as two MRI findings were contradictory. This article highlights the importance of suspicion of primary brain tumours in adults presenting with atypical neuropsychiatric manifestations.

O-ARM navigation in tubular retractor-assisted minimal invasive parafascicular approach: technical note

Trans-sulcal minimally invasive parafascicular surgery is an emerging technique to approach deep lesions with minimal brain retraction. Localization of the tubular retractor during surgery is critical, and intraoperative magnetic resonance imaging and neuronavigation present limitations. We describe the intraoperative use of O-Arm® coupled with pre-operative tractography to precisely localize the tubular retractor. With air acting as contrast, the tubular retractor was localized in three dimensions, without any additional disruption to white matter tracts or nearby vascular structures. We conclude that visualization of tubular retractor using an intraoperative computerized tomography scan is a safe and feasible adjunct in resection of deep lesions via a minimally invasive approach.

Outcomes of Stereotactic Radiation Therapy Versus Fractionated Radiation Therapy in 44 Dogs With Pituitary Masses: A Multi-Institutional Retrospective Study (2016-2022)

Although canine pituitary masses (PM) are increasingly treated with stereotactic radiotherapy (SRT), historical literature supports superior outcomes with conventional full-course fractionated radiation therapy (FRT). A multi-institutional retrospective study was performed, including dogs with PM treated from 2016 to 2022 with SRT (total dose 30 or 35 Gy in 5 daily fractions) or FRT (total dose 50-54 Gy in 19-20 daily fractions). The influence of potential prognostic/predictive factors was assessed, including pituitary: brain height, pituitary: brain volume, sex, age and endocrine status (functional [F] vs. nonfunctional [NF] PM). Forty-four dogs with PM were included (26 F, 14 NF, 4 unknown). All patients completed protocols as scheduled (SRT = 27, FRT = 17) and two dogs had suspected Grade 1 acute neurotoxicity. During the first 6 months after RT, 5/27 (19%) dogs treated with SRT (4 F, 1 NF) and 3/17 (18%) dogs treated with FRT (all F) died or were euthanised because of progressive neurologic signs. The overall median survival time was 608 days (95% CI, 375-840 days). Young age at the time of treatment was significant for survival (p = 0.0288); the overall median survival time was 753 days for dogs <9 years of age (95% CI, 614-892 days) and 445 days for dogs ≥9 years of age (95% CI, 183-707 days). Survival time was not associated with treatment type or any other factor assessed herein. A prospective study using standardised protocols would further validate the results of the present study and potentially elucidate the predictors of early death.

Magnetic resonance and computed tomographic imaging characteristics and potential molecular mechanisms of feline meningioma associated calvarial hyperostosis

Meningiomas are the most common feline primary brain tumours, and calvarial hyperostosis (CH) is frequently documented in association with this neoplastic entity. The clinical significance of and mechanisms driving the formation of CH in cats with meningiomas are poorly understood, although tumour invasion into the skull and tumour production of cytokines and enzymes have been implicated as causes of CH in humans. This retrospective study investigated relationships between signalment, MRI or CT imaging features, histopathologic tumour characteristics, alkaline phosphatase (ALP) isoenzyme concentrations, tumour expression of matrix metalloproteinases (MMP)-2, MMP-9, and interleukin-6 (IL-6), and progression free survival times (PFS) following surgical treatment in 27 cats with meningiomas with (n = 15) or without (n = 12) evidence of CH. No significant differences in breed, age, sex, body weight, tumour grade, tumour volume, peritumoral edema burden, ALP isoenzyme concentrations, tumour Ki-67 labelling indices or MMP-2 or MMP-9 expression and activity, or PFS were noted between cats with or without CH. There was a trend towards higher serum (p = .06) and intratumoral (p = .07) concentrations of IL-6 in cats with CH, but these comparisons were not statistically significant. Histologic evidence of tumour invasion into bone was observed in 5/12 (42%) with CH and in no (0/6) cats without CH, although this was not statistically significant (p = .07). Tumour invasion into bone and tumour production of IL-6 may contribute to the formation of meningioma associated CH in cats, although larger studies are required to further substantiate these findings and determine their clinical relevance.

Papillary glioneuronal tumor: a case report of the cerebral aqueduct and review of literature

Papillary glioneuronal tumour is an entity described as grade I neuronal-glial tumour by the World Health Organization. Headaches, seizures, vomiting, language or visual disturbances, and hemiparesis are the most common clinical findings. This tumour typically presents as cystic with enhancing mural nodule in the cerebral hemisphere. In this paper, we reported a case of a papillary glioneuronal tumour in a young adult whose magnetic resonance imaging revealed a solid tumour in the cerebral aqueduct. The tumour was totally resected surgically 13 years ago. The histological and immunohistochemical examination determined the diagnosis. No further therapy was necessary. Currently, the patient presents no neurologic signs or symptoms and there is no radiologic evidence of tumour relapse. The case of papillary glioneuronal tumour reported here displayed unusual location and radiologic features. The long duration of follow-up of this case with no tumour relapse enhances that the preferred management for this type of tumour is its total surgical resection.

Exploring the neural basis of non-invasive prehabilitation in brain tumour patients: An fMRI-based case report of language network plasticity

Primary brain neoplasms are associated with elevated mortality and morbidity rates. Brain tumour surgery aims to achieve maximal tumour resection while minimizing damage to healthy brain tissue. Research on Neuromodulation Induced Cortical Prehabilitation (NICP) has highlighted the potential, before neurosurgery, of establishing new brain connections and transfer functional activity from one area of the brain to another. Nonetheless, the neural mechanisms underlying these processes, particularly in the context of space-occupying lesions, remain unclear. A patient with a left frontotemporoinsular tumour underwent a prehabilitation protocol providing 20 sessions of inhibitory non-invasive neuromodulation (rTMS and multichannel tDCS) over a language network coupled with intensive task training. Prehabilitation resulted in an increment of the distance between the tumour and the language network. Furthermore, enhanced functional connectivity within the language circuit was observed. The present innovative case-study exposed that inhibition of the functional network area surrounding the space-occupying lesion promotes a plastic change in the network's spatial organization, presumably through the establishment of novel functional pathways away from the lesion's site. While these outcomes are promising, prudence dictates the need for larger studies to confirm and generalize these findings.

Profiling of circulating glial cells for accurate blood-based diagnosis of glial malignancies

Here, we describe a blood test for the detection of glial malignancies (GLI-M) based on the identification of circulating glial cells (CGCs). The test is highly specific for GLI-M and can detect multiple grades (II-IV) and subtypes including gliomas, astrocytomas, oligodendrogliomas, oligoastrocytomas and glioblastomas, irrespective of gender and age. Analytical validation of the test was performed as per Clinical and Laboratory Standards Institute (CLSI) guidelines. Real-world performance characteristics of the test were evaluated in four clinical (observational) studies. The test has high analytical sensitivity (95%), specificity (100%) and precision (coefficient of variation [CV] = 13.7% for repeatability and CV = 23.5% for within laboratory precision, both at the detection threshold) and is not prone to interference from common drugs and serum factors. The ability of the test to detect and differentiate GLI-M from non-malignant brain tumours (NBT), brain metastases from primary epithelial malignancies (EPI-M) and healthy individual donors (HD) was evaluated in four clinical cohorts. Across these clinical studies, the test showed 99.35% sensitivity (95% confidence interval [CI]: 96.44%-99.98%) and 100% specificity (95% CI: 99.37%-100%). The performance characteristics of this test support its clinical utility for diagnostic triaging of individuals presenting with intracranial space-occupying lesions (ICSOL).

The need for hair removal in paediatric brain tumour surgery?

INTRODUCTION

Preoperative hair removal is conventional practice within neurosurgery in an attempt to maintain antisepsis. However, there is a lack of evidence to suggest that it makes a difference with regards to infection. This article aims to relate preoperative hair removal to SSIs for paediatric patients.

METHODS AND MATERIALS

A retrospective analysis was conducted from a single paediatric neurosurgical database at the University Hospital of Wales. Patients were grouped according to whether they underwent preoperative hair removal or not. Findings were reviewed in light of the previously published literature.

RESULTS

One hundred eighty two paediatric intracranial tumours were operated on between November 2008 and 2019. A total of twenty-six patients (14%) developed an infection post-operatively, of which meningitis was the most common (77%). Eighty-nine operations were undertaken without preoperative hair removal, of which there were a total of fifteen infections (17%). In the hair removal group, there were a total of eleven infections out of ninety-three operations (12%). Overall, the patients without hair removal had a higher infection rate when compared to those with hair removal (17 and 12% respectively), however, this result was not statistically significant (p-value 0.3989).

CONCLUSION

We did not find evidence that hair removal in paediatric neurosurgery effects postoperative infection risk.

Preserving the ability to discriminate between left and right; A case study

Left-right orientation, a function related to the parietal lobe, is important for many daily activities. Here, we describe a left-handed patient with a right parietal brain tumour. During awake surgery, electric stimulation of the right inferior parietal lobe resulted in mistakes in his left-right orientation. Postoperatively our patient had no problems in discriminating left right. This case report shows that monitoring of left-right orientation during awake brain tumour surgery is feasible so that this function can be preserved.

Blunted perception of breathlessness in three cases of low grade insular-glioma

Better understanding of breathlessness perception addresses an unmet clinical need for more effective treatments for intractable dyspnoea, a prevalent symptom of multiple medical conditions. The insular-cortex is predominantly activated in brain-imaging studies of dyspnoea, but its precise role remains unclear. We measured experimentally-induced hypercapnic air-hunger in three insular-glioma patients before and after surgical resection. Tests involved one-minute increments in inspired CO2, raising end-tidal PCO2 to 7.5 mmHg above baseline (38.5 ± 5.7 mmHg), whilst ventilation was constrained (10.7 ± 2.3 L/min). Patients rated air-hunger on a visual analogue scale (VAS). Patients had lower stimulus-response (2.8 ± 2 vs. 11 ± 4 %VAS/mmHg; p = 0.004), but similar threshold (40.5 ± 3.9 vs. 43.2 ± 5.1 mmHg), compared to healthy individuals. Volunteered comments implicated diminished affective valence. After surgical resection; sensitivity increased in one patient, decreased in another, and other was unable to tolerate the ventilatory limit before any increase in inspired CO2.We suggest that functional insular-cortex is essential to register breathlessness unpleasantness and could be targeted with neuromodulation in chronically-breathless patients. Neurological patients with insula involvement should be monitored for blunted breathlessness to inform clinical management.

A Feasibility Study on a Portable Vision Device for Patients with Stroke and Brain Tumours

This prospective, single-centre cohort study aimed to evaluate the impact of a portable vision reading device, OrCam Read, on vision-related quality-of-life and independent functional status in patients with low vision due to stroke or brain tumours. Six patients with poor visual acuity or visual field defects due to a stroke or a brain tumour were enrolled at a U.S. Ophthalmology Department. Participants were trained to use OrCam Read and given a loaner device for the 1 month duration of the study. Various assessments, including daily function tests, the National Eye Institute Visual Function Questionnaire-25, and the 10-item neuro-ophthalmic supplement, were administered at the first and last visits. Patients' experience with the device was evaluated with weekly telephone and end-of-study satisfaction surveys. The main outcome measures were the patient satisfaction with OrCam and the mean assessment scores between enrolment and final visits. The intervention with OrCam significantly improved patients' ability to complete daily tasks and participants reported good satisfaction with the device. The results also show non-significant improvement with distant activities, dependency, and role difficulties. Our findings demonstrate the feasibility of studying vision-related quality-of-life using a portable vision device in this patient population and pave the way for a larger study to validate the results of this study.

Brain tumour detection from magnetic resonance imaging using convolutional neural networks

Introduction

The aim of this work is to detect and classify brain tumours using computational intelligence techniques on magnetic resonance imaging (MRI) images.

Material and methods

A dataset of 3264 MRI brain images consisting of 4 categories: unspecified glioma, meningioma, pituitary, and healthy brain, was used in this study. Twelve convolutional neural networks (GoogleNet, MobileNetV2, Xception, DesNet-BC, ResNet 50, SqueezeNet, ShuffleNet, VGG-16, AlexNet, Enet, EfficientB0, and MobileNetV2 with meta pseudo-labels) were used to classify gliomas, meningiomas, pituitary tumours, and healthy brains to find the most appropriate model. The experiments included image preprocessing and hyperparameter tuning. The performance of each neural network was evaluated based on accuracy, precision, recall, and F-measure for each type of brain tumour.

Results

The experimental results show that the MobileNetV2 convolutional neural network (CNN) model was able to diagnose brain tumours with 99% accuracy, 98% recall, and 99% F1 score. On the other hand, the validation data analysis shows that the CNN model GoogleNet has the highest accuracy (97%) among CNNs and seems to be the best choice for brain tumour classification.

Conclusions

The results of this work highlight the importance of artificial intelligence and machine learning for brain tumour prediction. Furthermore, this study achieved the highest accuracy in brain tumour classification to date, and it is also the only study to compare the performance of so many neural networks simultaneously.

Exploring the experiences of adults adjustment when living with a primary brain tumour

BACKGROUND

Brain tumours are the ninth most common cancer in the UK, and account for 3% of all new cancer cases.

AIM

To understand the impact of living with a primary brain tumour and identify adjustments that patients make in order to cope with their condition. This also encomapsses the impact of interventions like support groups in terms of care and therapeutic value.

METHODS

After ethical approval, a qualitative approach was employed, which set out to interview 11 adult patients living with primary brain tumours. The interviews were conducted face-to-face and were semi-structured interviews. Interview data were coded and thematic analysis used.

FINDINGS

Four themes were developed, namely: adjustment; loss of independence; support; and health and symptoms.

CONCLUSION

Living with a brain tumour leads to an inevitable adjustment to maintain day-to-day life. The findings suggest there are a number of adjustments that patients make to maintain some independence. Many people valued the support they received from support groups, while others felt that the support they received was inadequate. The mandatory loss of a driving licence for people in the UK was the most concerning. Its removal led to a loss of confidence and made them immediately dependent on others for travel. While support was provided, there was an apparent omission in the provision of psychological support. Oncology and palliative care nurses are in key positions to explore psychological concerns and offer tailored support.

Key Questions on the Long-Term Utility of Methylphenidate in Paediatric Brain Tumour Survivorship: A Retrospective Clinical Case Series

Methylphenidate has an established role in the management of attention-deficit hyperactivity disorder and attentional deficit secondary to brain injury. Increasingly, methylphenidate is considered for the attentional deficit in paediatric brain tumour survivors. A small number of studies have explored the benefit of methylphenidate in this population; however, studies are of short duration and do not address the impact of medium to long-term use of methylphenidate on intellectual function. We identified six patients who are survivors of a paediatric brain tumour aged 12-18 years with greater than three years of use of methylphenidate for inclusion in a clinical case series. We used this patient cohort to identify key questions to inform a future long-term cohort study. Linear mixed model and reliable change index analyses were performed on the data. Reliable change index analyses showed benefits to working memory (n = 3), processing speed (n = 2), and full-scale IQ (n = 4) performance for some patients. This exploratory case series suggests the potential medium to long-term benefit of methylphenidate in brain tumour survivorship, indicating the need for larger, appropriately powered studies. These patient data, alongside a discussion of learning points from our previously published studies, are used as a conduit for the identification of questions relating to the use of methylphenidate in a paediatric brain tumour.

A retrospective analysis of the ethnicity of individuals referred to a tertiary neuropsychology service in the United Kingdom

Objective: Ethnic minorities comprise approximately 18% of the UK population and are at high risk of developing neurological conditions. Despite this, there is little information regarding their access to neuropsychology services. This study evaluated whether ethnic minorities were proportionally represented in a tertiary neuropsychology department in the UK in accordance with census data for the region. We also aimed to highlight which ethnic groups were over- and underrepresented. Method: Anonymised demographic data of 3429 outpatient and 3304 inpatient referrals to an adult UK neuropsychology department was collected. These data were compared to the 2021 UK census data for the region. Results: Ethnicities in both the outpatient referrals (χ2(15) = 24066.55, p < .001) and inpatient referrals (χ2(15) = 35940924.75, p < .001) are significantly different from the Census. All ethnic minorities were underrepresented in adult neuropsychology referral data for both outpatient settings (-0.06% to -4.66%) and inpatient settings (-0.01% to -4.99%). Pakistani individuals were the most underrepresented across all settings, followed by individuals from an African background. Conversely, individuals of White British ethnicity were overrepresented in both outpatient settings (+10.73%) and inpatient settings (+15.68%). Conclusions: The UK ethnic minorities were not referred to a neuropsychology service relative to regional population prevalence. This contradicts their increased susceptibility for risk of neurological conditions but may also indicate the inaccessibility of neuroscience services for ethnic minorities. Replicating this study across different regions and gathering data on prevalence rates for different neurological conditions across ethnicity is recommended. Additionally, improving accessibility of neuropsychology services for British ethnic minorities should be prioritised.

The Multi-Modal Evaluation of Sensory Sensitivity (MESSY): Assessing a commonly missed symptom of acquired brain injury

Objective: Sensory hypersensitivity is common after acquired brain injury. Since appropriate diagnostic tools are lacking, these complaints are overlooked by clinicians and available literature is limited to light and noise hypersensitivity after concussion. This study aimed to investigate the prevalence of sensory hypersensitivity in other modalities and after other types of brain injury. Method: We developed the Multi-Modal Evaluation of Sensory Sensitivity (MESSY), a patient-friendly questionnaire that assesses sensory sensitivity across multiple sensory modalities. 818 neurotypical adults (mean age = 49; 244 male) and 341 chronic acquired brain injury patients (including stroke, traumatic brain injury, and brain tumour patients) (mean age = 56; 126 male) completed the MESSY online. Results: The MESSY had a high validity and reliability in neurotypical adults. Post-injury sensory hypersensitivity (examined using open-ended questions) was reported by 76% of the stroke patients, 89% of the traumatic brain injury patients, and 82% of the brain tumour patients. These complaints occurred across all modalities with multisensory, visual, and auditory hypersensitivity being the most prevalent. Patients with post-injury sensory hypersensitivity reported a higher sensory sensitivity severity on the multiple-choice items of the MESSY as compared to neurotypical adults and acquired brain injury patients without post-injury sensory hypersensitivity (across all sensory modalities) (effect sizes (partial eta squared) ranged from .06 to .22). Conclusions: These results show that sensory hypersensitivity is prevalent after different types of acquired brain injury as well as across several sensory modalities. The MESSY can improve recognition of these symptoms and facilitate further research.

Changes in frontal aslant tract tractography in selected types of brain tumours

AIM OF THE STUDY

To present differences in frontal aslant tract (FAT) tractography among patients diagnosed with primary brain tumours and metastatic brain tumours.

MATERIAL AND METHODS

The analysis included 38 patients diagnosed with a frontal brain tumour. A control group of 30 healthy patients was also considered. The FAT was delineated, taking into account ROI 1 - the superior frontal gyrus, and ROI 2 - SMA. Endpoints were determined on the pars opercularis and pars triangularis of the inferior frontal gyrus. FAT was delineated in four different ways for each patient.

RESULTS

In the group of patients with a brain tumour, a lower volume of FAT and a reduced quantity of fibres were observed compared to the control group. Comparison of the examined parameters between patients with glioblastoma and metastasis revealed statistically significant differences for MD (p < 0.001) regardless of the selected projection.

CONCLUSIONS

The difference in MD (mean diffusivity) among patients with metastatic tumours may be related to an increased oedema zone.

The Role of Progranulin (PGRN) in the Pathogenesis of Glioblastoma Multiforme

Glioblastoma multiforme (GBM) represents the most common and aggressive malignant form of brain tumour in adults and is characterized by an extremely poor prognosis with dismal survival rates. Currently, expanding concepts concerning the pathophysiology of GBM are inextricably linked with neuroinflammatory phenomena. On account of this fact, the identification of novel pathomechanisms targeting neuroinflammation seems to be crucial in terms of yielding successful individual therapeutic strategies. In recent years, the pleiotropic growth factor progranulin (PGRN) has attracted significant attention in the neuroscience and oncological community regarding its neuroimmunomodulatory and oncogenic functions. This review of the literature summarizes and updates contemporary knowledge about PGRN, its associated receptors and signalling pathway involvement in GBM pathogenesis, indicating possible cellular and molecular mechanisms with potential diagnostic, prognostic and therapeutic targets in order to yield successful individual therapeutic strategies. After a review of the literature, we found that there are possible PGRN-targeted therapeutic approaches for implementation in GBM treatment algorithms both in preclinical and future clinical studies. Furthermore, PGRN-targeted therapies exerted their highest efficacy in combination with other established chemotherapeutic agents, such as temozolomide. The results of the analysis suggested that the possible implementation of routine determinations of PGRN and its associated receptors in tumour tissue and biofluids could serve as a diagnostic and prognostic biomarker of GBM. Furthermore, promising preclinical applications of PGRN-related findings should be investigated in clinical studies in order to create new diagnostic and therapeutic algorithms for GBM treatment.

Classification of Brain Tumours in MRI Images using a Convolutional Neural Network

INTRODUCTION

Recent advances in deep learning have aided the well-being business in Medical Imaging of numerous disorders like brain tumours, a serious malignancy caused by unregulated and aberrant cell portioning. The most frequent and widely used machine learning algorithm for visual learning and image identification is CNN.

METHODS

In this article, the convolutional neural network (CNN) technique is used. Augmentation of data and processing of images is used to classify scan imagery of brain MRI as malignant or benign. The performance of the proposed CNN model is compared with pre-trained models: VGG-16, ResNet-50, and Inceptionv3 using the technique which is transfer learning.

RESULTS

Even though the experiment was conducted on a relatively limited dataset, the experimental results reveal that the suggested scratched CNN model accuracy achieved is 94 percent, VGG-16 was extremely effective and had a very low complexity rate with an accuracy of 90 percent, whereas ResNet- 50 reached 86 percent and Inception v3 obtained 64 percent accuracy.

CONCLUSION

When compared to previous pre-trained models, the suggested model consumes significantly less processing resources and achieves significantly higher accuracy outcomes and reduction in losses.

Lipid content evaluation of Drosophila tumour associated haemocytes through Third Harmonic Generation measurements

Non-linear microscopy is a powerful imaging tool to examine structural properties and subcellular processes of various biological samples. The competence of Third Harmonic Generation (THG) includes the label free imaging with diffraction-limited resolution and three-dimensional visualization with negligible phototoxicity effects. In this study, THG records and quantifies the lipid content of Drosophila haemocytes, upon encountering normal or tumorigenic neural cells, in correlation with their shape or their state. We show that the lipid accumulations of adult haemocytes are similar before and after encountering normal cells. In contrast, adult haemocytes prior to their interaction with cancer cells have a low lipid index, which increases while they are actively engaged in phagocytosis only to decrease again when haemocytes become exhausted. This dynamic change in the lipid accrual of haemocytes upon encountering tumour cells could potentially be a useful tool to assess the phagocytic capacity or activation state of tumour-associated haemocytes.

Comparative study between dynamic susceptibility contrast magnetic resonance imaging and arterial spin labelling perfusion in differentiating low-grade from high-grade brain tumours

Purpose

Our aim was to distinguish between low-grade and high-grade brain tumours on the basis of dynamic susceptibility contrast (DSC) magnetic resonance imaging (MRI) perfusion and arterial spin labelling (ASL) perfusion and to compare DSC and ASL techniques.

Material and methods

Forty-one patients with brain tumours were evaluated by 3-Tesla MRI. Conventional and perfusion MRI imaging with a 3D pseudo-continuous ASL (PCASL) and DSC perfusion maps were evaluated. Three ROIs were placed to obtain cerebral blood value (CBV) and cerebral blood flow (CBF) in areas of maximum perfusion in brain tumour and normal grey matter. Histopathological diagnosis was considered as the reference. ROC analysis was performed to compare the diagnostic performance and to obtain a feasible cut-off value of perfusion parameters to differentiate low-grade and high-grade brain tumours.

Results

Normalised perfusion parameters with grey matter (rCBF or rCBV lesion/NGM) of malignant lesions were significantly higher than those of benign lesions in both DSC (normalised rCBF of 2.16 and normalised rCBV of 2.63) and ASL (normalised rCBF of 2.22) perfusion imaging. The normalised cut-off values of DSC (rCBF of 1.1 and rCBV of 1.4) and ASL (rCBF of 1.3) showed similar specificity and near similar sensitivity in distinguishing low-grade and high-grade brain tumours.

Conclusions

Quantitative analysis of perfusion parameters obtained by both DSC and ASL perfusion techniques can be reliably used to distinguish low-grade and high-grade brain tumours. Normalisation of these values by grey matter gives us more reliable parameters, eliminating the different technical parameters involved in both the techniques.