Frontal Lobe Tumor Research Articles

SURG-07. QUANTIFYING THE RISK OF SHORT TERM SEIZURES FOLLOWING LASER INTERSTITIAL THERMAL THERAPY

Abstract BACKGROUND Tumor-related epilepsy is a common sequela of both primary and metastatic brain tumors, as well as radiation necrosis (RN). Laser interstitial thermal therapy (LITT) is an effective option for lesional cytoreduction but induces transient peritumoral edema that typically resolves within 3 months of the procedure. Accordingly, we quantified the risk of seizure development early post-LITT in patients with tumors or RN of diverse histologies. METHODS Patients treated with LITT for brain tumors or radiation necrosis at a high-volume center from 2015 – 2021 with at least 3 months of clinical follow-up were evaluated for seizure risk and time to discontinuation of anti-epileptic drugs (AEDs) for at least 4 weeks, with censoring at death or last follow-up. RESULTS One-hundred and seventeen patients met inclusion criteria, and 22 (19%) experienced a post-LITT seizure within 3 months of surgery. Those with pre-LITT seizures (P = 0.03), prior whole-brain radiation (WBRT) (P = 0.0099), or lower pre-operative KPS (P = 0.04) were more likely to have a post-LITT seizure. Frontal lobe tumors appeared to be more frequently associated with seizures (68% vs 45%, P = 0.06). Prior WBRT, odds ratio (OR) 4.27 (95% CI 1.01 – 18.55), P = 0.047 and pre-LITT seizure, OR 5.39 (95% CI 1.87 – 16.31), P = 0.002 remained predictive on multivariate analyses. Successful AED weaning occurred at a median of 1.68 months (no seizure within 3-months group) versus undefined for patients experiencing seizures (P = 0.015). Post-LITT seizures within 3 months were associated with worsened post-LITT overall survival, 5.95 vs 17.2 months, P < 0.0001. DISCUSSION Prior seizure history or previous WBRT pose a risk of breakthrough seizures following laser ablation. Neurosurgeons should consider extended AED treatment or referral for management of tumor-related epilepsy in patients with these neurologic risk factors.

Lately Obtained Baseline Waves in Motor Evoked Potential Monitoring during the Surgery of Frontal Lobe Tumor

Intraoperative neurophysiologic monitoring during brain tumor surgery should acquire a baseline data as soon as possible. However, motor unit potentials (MEP) in our case showed baseline data could not be acquired in the early stage of surgery, but consecutive trials had abrupt appearance of MEP just after dura opening. This case shows the acquisition of baseline MEP during brain tumor surgery should not be given up until the dura is open especially in a state of raised intracranial pressure.

Comparison of Awake Craniotomy with Craniotomy Under General Anesthesia for Resection of Tumors in Eloquent Areas of Brain

Objective: To compare awake craniotomy with craniotomy under general anesthesia for early post-operative parameters in patients undergoing resection of tumors in eloquent areas of brain. Study Design: Quasi experimental study. Place and Duration of Study: Department of Anesthesia, Combined Military Hospital, Rawalpindi Pakistan Apr 2021 to May 2022. Methodology: All the patients who underwent resection surgeries for brain tumors in eloquent areas of brain were included in the study. They were divided into two Groups via lottery method. Group A underwent awake craniotomy while Group B underwent craniotomy under general anesthesia. Relevant intraoperative and early post-operative parameters were compared in both the Groups. Results: A total of 60 patients who underwent resection of eloquent area brain tumors in our hospital during the study period were included in the final analysis. Out of these 40(66.7%) underwent craniotomy under general anesthesia while 20(33.3%) underwent awake craniotomies. Mean age of the study participants was 45.61±7.889 years. Frontal lobe tumors were the most encountered brain tumors in our study participants. Patients who underwent awake craniotomy had statistically significantly lower KORNAFSKY score, lesser days of post-operative admission days and lesser neurological deficits (p-value <0.005) as compared to those who underwent craniotomy under general anesthesia. Conclusion: Awake craniotomy emerged as superior option as compared to craniotomy under general anesthesia in terms of early post-operative parameters. Lower KORNAFSKY score, lesser days of post-operative admission days and lesser neurological deficits were seen in patients undergoing awake craniotomy.

Awake Surgery for Right Frontal Lobe Glioma: Preserving Emotional Recognition and Facilitating Early Return to Work.

Many glioma patients struggle to return to work after surgery because of higher brain dysfunction. Although the right frontal lobe has historically been considered functionally silent, reports of performing awake surgery to evaluate higher brain functions in patients with tumors in this area have increased. We present two cases of patients who underwent awake surgery for malignant glioma in the right frontal lobe to preserve emotional recognition and facilitate an early return to work. Case 1 was a 48-year-old right-handed woman employed as a nursery school teacher and case 2 was a 21-year-old right-handed man employed in sales. Both had contrast-enhancing right frontal lobe tumors exhibiting high signal intensity on fluid attenuated inversion recovery imaging and underwent awake surgery. During the operation, cortical mapping was performed using the Reading the Mind in the Eyes, calculation, and motor tasks. Resection of sites involved in motor and emotional recognition functions was avoided. In case 1, all regions of high signal intensity were completely resected; in case 2, all regions exhibiting enhancement were resected. Both patients were discharged home without neurological deficits and returned to work within 21 days after surgery. It may be important to focus not only on overall survival and progression-free survival in glioma patients, but also on factors associated with life satisfaction, such as time to return to work after surgery and time until work becomes difficult. Awake surgery aimed at preserving higher brain functions is useful and may also improve life satisfaction.

A - 143 Organic Psychiatric Disorders Due to Frontal Lobe Neoplasms

Abstract Objective This current study seeks to explore the presentation of psychiatric disorders as a preliminary symptom in individuals who suffer from frontal lobe neoplasms. Data Selection The primary sources of information for this literature review were Google Scholar, PubMed, ScienceDirect, and the National Institute of Health (NIH). Search terms included frontal lobe tumors/neoplasms, primary brain tumors, psychiatric/psychological, acquired disorders, and pseudo-depression/mania. This search was limited to articles published in English from January 2014 to December 2023. Inclusion criteria were studies that focused on frontal lobe tumors and psychiatric manifestations as a result of illness. Exclusion criteria were studies older than nine years or studies that explored traits of psychiatric illness (i.e., aggression) as opposed to a psychiatric diagnosis. Data Synthesis Frontal lobe neoplasms, accounting for a significant percentage of PTBs, have been found to impact the psychological well-being of patients, leading to a range of psychiatric manifestations that may appear before physiological symptoms. These include mood disorders (i.e., depression, manic episodes), psychotic episodes, and personality disorders. Due to the complexities of the frontal lobe, these manifestations are not linearly linked to frontal lobe lesions. Conclusion This study’s findings advocate for a multidisciplinary approach to treatment, emphasizing the need for neuropsychological evaluations pre- and post-tumor resection. It calls for heightened awareness among clinicians to consider organic causes behind psychiatric presentations, especially in atypical cases or when traditional treatments fail. Ultimately, this research contributes to a deeper understanding of the neuropsychiatric consequences of frontal lobe neoplasms and paves the way for more targeted and effective interventions.

Retinal Microstructural Changes Reflecting Treatment-Associated Cognitive Dysfunction in Patients with Lower-Grade Gliomas

PurposeTo determine whether microstructural retinal changes, tumor features, and Apolipoprotein E (APOE) ε4 polymorphism are correlated with clinically detectable treatment-associated cognitive dysfunction (TACD) in patients with lower-grade gliomas. DesignCohort study. Participants and ControlsSixteen lower-grade glioma patients at a U.S. academic Ophthalmology department between January 2021 and November 2023. Normal controls were recruited from convenient sampling. MethodsMontreal Cognitive Assessment (MoCA) scores and retinal changes were assessed in 6-months intervals. APOE genotyping was performed, and tumor details were recorded. Partial least-squares discriminant (PLSD) model was established to evaluate the association between TACD with APOE genotype, ophthalmic, and tumor features. Main Outcome MeasuresThe main outcome measure was cognitive status as measured by the MoCA score and analyzed in relation to ophthalmic measurements, tumor features, and APOE genotype. ResultsMedian time to first eye exam was 34 months (2–266) from tumor diagnosis and 23 months (0–246) from radiation. Nine patients (56%) had abnormal cognition (MoCA <26/30). MoCA scores were significantly worse in patients with temporal (22±7.2) than frontal lobe tumors (26±3.1, p=0.02) and those with oligodendrogliomas (22±4.1) than astrocytomas (26±3.6, =0.02). Patients with TACD had significant radial peripapillary capillary density loss (45%±4.6) compared to those with normal cognition (49%±2.6, p=0.02). A PLSD model correlated MoCA scores with retinal nerve fiber thickness, intraocular pressure, foveal avascular zone, best-corrected visual acuity, months since first diagnosis, and tumor pathology (oligodendroglioma or not). Using these features, the model identified patients with TACD with 77% accuracy. APOE genotyping showed: two ε2/ε3 (13%), ten ε3/ε3 (63%), and one ε3/ε4 (6%). ConclusionRetinal microstructural changes may serve as biomarkers for TACD in patients with lower-grade gliomas. Temporal lobe tumors and oligodendrogliomas may increase susceptibility to TACD. Utilization of retinal markers may enhance TACD diagnosis, progression monitoring, and inform management of lower-grade glioma patients. A larger study with serial eye exams is warranted to evaluate the role of APOE ε4 and develop a predictive model.

Acquired Ptosis in Patient with Suspect Meningiomatosis

Background: Ptosis is abnormally low positioned upper eyelid. It can be classified as congenital and acquired. Meningiomas are mostly benign tumors originating from meningothelial (arachnoid) cells (MECs). A subset of meningioma patients bears two or more spatially separated synchronous or metachronous tumors termed “Multiple Meningiomas” (MM) or meningiomatosis. Case: A 51-year-old female complained the dizziness was associated with nausea and emetic episodes. She reported any blurred vision and woke up with the dropped eyelid. Prior to this she had double vision and light headedness that she had 3 months before. The ophthalmic examination presented partial left ptosis and the patient's left eye was shifted towards the lateral edge at rest. CT scan with contrast presented multiple solid masses, extra axial, homogeneous, strong contrast enhancement with calvaria hyperostosis and perifocal edema in the left frontal region and left temporoparietal region. Discussion: Ptosis in the left eye and exotropia is consistent with a left oculomotor nerve palsy. CT scan with contrast confirmed multiple solid masses leaning towards meningiomatosis. In this case, patient-acquired ptosis could be caused by direct oculomotor compression of the frontal lobe tumor, the tumor site being close to the superior orbital fissure. Conclusion: Stemming from third cranial nerve dysfunction, multiple solid masses in the left frontal region indicate meningiomatosis. Acquired ptosis may result from direct compression of the oculomotor nerve by the frontal lobe tumor. While surgery is the primary treatment for meningiomas, corticosteroids may be considered in acute conditions to alleviate perifocal edema.

Incidence and risk factors of post-operative delirium in glioma patients: A prospective cohort study in general wards.

Glioma patients are at high risk for postoperative delirium (POD), yet studies focusing on this population in general neurosurgical ward settings are limited. This paper investigates the incidence of POD and related risk factors in glioma patients hospitalized in general wards. Prospective observational study. This prospective study included 133 adult glioma patients hospitalized in the general neurosurgery ward. In addition to collecting routine perioperative general clinical data, patients' psychological status was assessed preoperatively using the Hospital Anxiety and Depression Scale (HADS). POD was assessed within 3 days postoperatively using the Confusion of Consciousness Assessment method, twice daily. The incidence of POD was calculated, and risk factors were identified using logistic regression analysis. The incidence of POD in glioma patients admitted to the general ward was 31.6% (40/133). Multivariate regression revealed advanced age (age > 50 years), frontal lobe tumour, presence of preoperative anxiety or depression, retention of a luminal drain, postoperative pain, indwelling catheter these six factors were independent risk factors for the development of delirium in patients after surgery. In general ward settings, supratentorial glioma patients exhibit a high risk of POD. Critical risk factors include preoperative psychological conditions, as well as postoperative pain, drainage and catheterization. Rigorous preoperative evaluations, effective pain management strategies and the integration of humanistic care principles are essential in mitigating the risk of POD for glioma patients. In general ward settings, this study reveals the high occurrence of POD in glioma patients and identifies preoperative psychological states, age, tumour location and several postoperative factors as significant risk factors for POD, which provides a framework for targeted interventions. By integrating these insights into clinical practice, healthcare teams can better identify glioma patients at risk for POD and implement preventive measures, thereby enhancing recovery and overall care quality for glioma patients in general neurosurgical wards. This study adheres to the STROBE guidelines, ensuring a transparent and comprehensive reporting of the observational research methodology and results. Patients involvement was limited to the provision of data through their participation in the study's assessments and the collection of clinical information. The study did not involve a direct patient or public contribution in the design, conduct, analysis, or interpretation of the data, nor in the preparation of the manuscript.

Verbal learning in frontal patients: area 9 is critical for employing semantic strategies.

Learning is a long-term memory process heavily influenced by the control processes implemented by working memory, including recognition of semantic properties of items by which subjects generate a semantic structure of engrams. The aim of this study is to investigate the verbal learning strategies of patients affected by a tumor in the left frontal lobe to highlight the role of area 9. Ten patients with frontal low-grade gliomas and ten healthy control subjects, matched for age, sex and education, were recruited and then evaluated with a two-part verbal learning test: multi-trial word list learning in free recall, and multi-trial word list learning preceded by an explicit semantic strategy cue. Frontal patients were divided into two groups: those either with frontal lesions involving or sparing area 9. In comparison to healthy control subjects, frontal patients with lesions involving area 9 memorized fewer words and displayed difficulty in using semantic strategies. When the strategy was suggested by the examiner, their performance improved, but to a lesser extent than the healthy control. Conversely, frontal patients with lesions sparing area 9 showed similar results to healthy control subjects. The results suggested that, while the identification of the categorical criterion requires the integrity of the entire dorsolateral prefrontal area, only area 9, and not the surrounding areas, could be responsible for the effective use of semantic strategies in learning tasks.

Case Report and Literature review. Neuropsychiatry Manifestation of Frontal Lobe Neoplasm- Meningioma. Prevalence, Presentation and Pathogenesis

IntroductionMeningiomas are the most frequent primary brain tumor. Although most Meningiomas are benign, their location in the central nervous system can predict symptomatology which could result in significant morbidity and mortality. However, due to the slow-growing nature, meningiomas are usually asymptomatic, and diagnosis is often made incidentally on neuroimaging or at an autopsy. The incidence rate is 1.2-fold higher in Black Americans than White Americans. Neuropsychiatry manifestation might be only initial presentation; thus, psychiatrists are often the first to see these patients, and the correct diagnosis may be made only when the tumor has grown to a considerable size and begun to displace the brain.ObjectivesThe aim of this study is to understand the biological basis of psychiatry symptoms in patients with Frontal Lobe meningiomas.MethodsA review of literature and individual patient data analysis was conducted. The literature review was conducted on PubMed, Medline, MeSH, Google Scholar, and mount Sinai’s levy Library using the key words; meningioma, meningioma with psychiatric symptoms, psychosis, depression, neuropsychiatry manifestation of meningiomas.ResultsThe review revealed that 88% of brain tumors and psychiatric symptoms are located in the frontal region. Meningiomas accounts for 13%-26% of intracranial tumors. There is a reported low incidence due to its slow growing nature and are usually asymptomatic. Incidence of meningiomas is predominant in females, and is attributed to hormonal factors, this is associated with estrogen and progestogen cycles. Reports shows that smoking has been linked to increase risk of meningiomas in men. Frontal lobe meningiomas may present with only psychological symptoms that resemble depression, anxiety states, hypomania and schizophrenia. Personality and mental status changes are also noted in Frontal lobe tumors. Left sided lesions are associated with inhibition of motor activity, impairment in motor and initiative aspect of speech, diminished generalization ability and general inertia of mental process.Conclusions Given the absence of frank neurological symptoms, to help localize the lesion, most meningiomas are missed due to diagnostic overshadowing of the primary psychiatric illness. Peritumoral edema indicates the underlying mechanism and location of the lesion predicts symptomatology. Like our patient who is an 81-year-old male with no past psychiatry history, presenting to our comprehensive psychiatry emergency program with psychiatric manifestation as the initial presentation and subsequently with MRI suggestive of Right Frontal extra-axial meningioma. This study shows that primitive frontal lobe tumors are likely to be misdiagnosed as patients with such tumors are often referred first to psychiatrist. High index of suspicious is needed.Disclosure of InterestNone Declared

Altered functional connectivity in default mode network maintains attention task performance in school-age children with frontal lobe tumor

This study examines functional brain network changes in children with frontal lobe tumors (FLT). Ten pediatric FLT patients from Beijing Tiantan Hospital and 20 healthy children were compared in terms of cognitive performance and resting-state functional magnetic resonance imaging (rs-fMRI) connectivity. The FLT group showed lower cognitive performance, particularly in visual and working memory domains, but had comparable attention abilities to the healthy controls. There were notable differences in connectivity between the default mode network (DMN) and sensorimotor network (SMN) in both groups. The FLT group also displayed a significant reduction in local efficiency in the left lateral parietal area within the DMN. Importantly, reduced DMN-SMN connections and increased DMN-lateral prefrontal cortex connectivity may facilitate maintaining attention and memory tasks in FLT children. This study sheds light on how the brains of children with FLT adapt, preserving “normal” attention functions despite frontal lobe damage.

10143-COT-16 DIFFUSE BONE MARROW METASTASIS OF HIGH GRADE GLIOMA

Abstract BACKGROUND Extraneural metastasis of the high grade glioma has rarely been reported and its diffuse bone marrow metastasis is extremely rare. Case description: A 32-year-old man was referred and admitted to Shiga University of Medical Science Hospital for the treatment for three remote recurrent lesions in the brain after the treatment of the primary brain tumor in the right frontal lobe in the referring hospital. One of those lesions was subtotally resected, with histological and immunohistochemical analysis showing a grade 4 glioma, and stereotactic radiation therapy was performed at all three lesions. A lumbar spine MRI showed signal changes in the first and 4th vertebral bodies and the level of LDH was gradually increased during this hospitalization. Three months later, the patient was referred to our hospital again because of intractable lumbago with metastatic lesions in the lumbar vertebrae and the psoae major. Laboratory data showed pancytopenia and extremely elevated level of LDH-1 and LDH-2, suggesting aggressive hemolysis. Abdominopelvic CT also showed slight osteolytic changes in the ilia, sacra, and femurs. Biopsy of the psoas major and iliac bone marrow showed invasion of grade 4 glioma cells. The patient was diagnosed as having diffuse bone marrow metastasis of grade 4 glioma, and died 12 days after the second admission. CONCLUSIONS We have presented a rare case of diffuse bone marrow metastasis of high grade glioma. LDH elevation might mean hemolysis by bone marrow metastasis in patients with high grade glioma.

PATH-18. MORE UNUSUAL FEATURES IN H3 K27M-MUTANT GLIOMAS

Abstract Diffuse midline glioma, H3 K27M-altered, WHO grade 4 is an infiltrating midline glioma; however, H3 K27M mutation can also be seen in midline circumscribed, non-infiltrating gliomas and rarely in non-midline tumors. We report 2 unusual examples. A 37-year-old female developed a right posterior frontal infiltrating glioma; resection showed infiltrative tumor with brisk mitotic activity, elevated MIB-1 (20%), negative p53 expression, ATRX retention, but no necrosis or microvascular proliferation. Molecular workup showed neither IDH1/2/TERT promoter mutations or co-deletion 1p, 19q; further testing showed gain of whole chromosome 7 + loss of whole chromosome 10, meeting molecular criteria for glioblastoma. Recurrent tumor 2 years later in the same area prompted re-resection again of infiltrating tumor devoid of necrosis or microvascular proliferation; molecular testing now revealed a H3F3A (p.K28M) mutation. Both tumors showed protein expression by H3 K27M IHC+. She succumbed post-therapy at 3 ½ years. A 30-year-old woman developed a circumscribed, non-enhancing third ventricular mass; resection demonstrated circumscribed, non-infiltrating glioneuronal tumor with monotonous rounded tumor nuclei, synaptophysin IHC+, negative GFAP, H3 K27M IHC+, and low MIB-1. Molecular testing identified alterations in H3F3A p. K28M and FGFR1 p.N546K. She was treated, but lost to follow-up, until she re-presented 5 years later with hemorrhagic left frontal lobe tumor contiguous with the midline, with dorsal midbrain and 4th ventricular involvement. After resection, tumor now showed infiltrative features, necrosis and microvascular proliferation, diffuse GFAP IHC+, retention of nuclear ATRX, p53 (20%), MIB-1 (22%), and H3 K27M IHC+. New tumor had no FGFR1 alteration or PDGFRA amplification to suggest radiation-induced tumor, instead manifesting PTPRZ1-MET fusion. She survives at 5 years. These cases offer new insights into survival of a non-midline example and transformation of a circumscribed, non-infiltrating tumor to secondary infiltrating H3 K27-altered tumor with new molecular alterations, possibly representing second independent tumor development.

Bradycardia symptomatic causes headache associated with frontal diffuse astrocytoma: a case report

Background: Headache is the most common symptom in patients with brain tumors, whereas a developing brain tumor generally increases intracranial pressure and brain edema. Brain tumors have symptoms including nausea, vomiting, seizures, neurological deficits, and mental status or consciousness changes. Heart rhythm disturbances can occur, including bradycardia (heart rate below 60x/minute), a common symptom in brain tumor patients. Case Presentation: In this case report, a young adult male patient was found with headache symptoms, a previous history of syncope, and sinus bradycardia on the EKG examination, but on physical examination, there were no symptoms of neurological deficits. Head CT scan with contrast found a tumor in the left frontal lobe associated with high intracranial pressure and brain edema that explained the symptoms. Conclusion: The relationship between headache and bradycardia, accompanied by a history of syncope, is close and can be regarded as an early sign of a brain tumor. In this case, a brain tumor found based on pathological examination is diffuse astrocytoma.

DIPG-25. MAPPING TUMOR MICROENVIRONMENT USING EMERGING TECHNOLOGIES FOR PEDIATRIC BRAIN CANCERS

Abstract Diffuse midline glioma (DMG) is a fatal childhood brain cancer with a survival rate of less than one year from diagnosis. Pharmacological approaches as well as immunotherapy have failed to make a clinical impact. Incomplete understanding of the tumor microenvironment (TME) and tumor associated antigens have contributed to the observed poor prognosis. We hypothesize that characterization of the DMG TME will identify biology-informed targeted treatments. We thus obtained postmortem specimens from 70 patients diagnosed with brain cancers, including 50 DMGs, 20 other types and 10 non-CNS-cancer patients. Up to four anatomical brain locations were selected including the primary tumor, metastatic and adjacent healthy sites. Formalin-fixed-paraffin-embedded (FFPE) specimens were processed for constructing a tissue microarray (TMA). The TMA was stained for a number of markers (H&amp;E, H3K27M, H3K27me3, KI67) and was scored by a neuropathologist. We then used a multiplexed immunofluorescence (MxIF) technology, Cell DIVE™, to iteratively probe 33 biomarkers on a single tissue slide, focusing on immune cell type profiling and activation, and histone mutation status. Analysis of biomarker density and spatial relationships are underway. The main expressed immune markers across all patients were CD163, CD68, and CD8. CD8, a cytotoxic T-cell biomarker, was highly detected in pons, cerebellum, thalamus and the frontal lobe (tumor and healthy) of DMG patients and varied according to clinical intervention, including ONC201 treatment. Furthermore, in comparison to other tumors, DMGs exhibited a higher expression of CD3, T- cell marker, and CD4, a T-helper cell biomarker. Analysis of Iba1, a microglial marker, confirmed a higher difference in microglial activation in primary tumor compared to metastatic and adjacent healthy tissue. In contrast, CD68 was significantly increased in metastatic sites. Analysis is still ongoing. We report establishment of the most comprehensive TMA for pediatric brain tumors, which provides insights into TME comparing critically important clinical variables.

870 Association of MGMT Methylation With Response to Chemotherapy in WHO Grade 2 Low Grade Glioma

INTRODUCTION: The role of adjuvant chemotherapy (AC) in the treatment of low-grade glioma (LGG) has been an area of controversy. While of O6-methylgaunine-DNA-methyltransferase (MGMT) promoter methylation is a predictor of response to AC in high grade glioma, its relevance in LGG is uncertain. METHODS: Overall survival was evaluated using Kaplan-Meier estimates and multivariable Cox proportional hazards regression. Subgroup analyses were conducted in cohorts defined by tumor size, tumor location, histology, extent of resection, and receipt of radiation. RESULTS: Between 2004 and 2018, 1,139 participants were diagnosed with WHO grade 2 LGG (median [IQR] age, 40 years [31-53]; 578 were male [51%]; 614 were MGMT methylated (54%)). In multivariate analysis, among the 512 patients (45%) receiving AC, there was improved overall survival in methylated compared to unmethylated cohorts (hazard ratio [HR], 0.48; 95% CI, 0.32-0.72; p &lt; 0.001). This association was not demonstrated in patients without AC (HR, 1.01; 95% CI, 0.63-1.60; p=0.985). On subgroup analysis, MGMT methylation status was associated with an independent improved response to chemotherapy in subgroups of patients with no 1p/19q codeletion [astrocytoma], tumor diameter ≥50mml, tumor diameter &lt;50mm, frontal lobe tumors, radiotherapy, no radiotherapy, and subtotal resection MGMT methylation was not associated with improved response to chemotherapy in patients with 1p/19q codeletion [oligodendroglioma] or gross total resection. CONCLUSIONS: MGMT methylation status was associated with response to AC in adult astrocytic LGG, irrespective of treatment with radiation. This relationship was not present for oligodendroglioma. If replicated in contemporary trials, these findings will substantially guide treatment decisions for many LGG patients.

Early recovery of cognition and brain plasticity after surgery in children with low-grade frontal lobe tumors.

Low-grade frontal lobe tumors (LGFLT) can be cured through total resection, but surgical trauma could impair higher-order cognitive function. We aim to characterize the short-term natural cognitive recovery and brain plasticity in surgically-treated pediatric patients with LGFLT. Ten pediatric patients with LGFLT were enrolled. Their cognitive function was assessed before the surgery (S0), in the first month post-surgery (S1), and 3-6 months post-surgery (S2), using the CNS Vital Signs battery. DTI and rs-fMRI were performed during the same time periods. Changes of cognition and image metrics between S1>S0 and S2>S1 were analyzed. The Motor Speed (MotSp) and Reaction Time (RT) scores significantly decreased in S1 and recovered in S2. Rs-fMRI showed decreased functional connectivity (FC) between the bilateral frontal lobes and bilateral caudates, putamina, and pallidi in S1>S0 (voxel threshold , cluster threshold ). In S2>S1, FC recovery was observed in the neighboring frontal cortex areas ( , ). Among them, the FC in the caudates-right inferior frontal gyri was positively correlated to the RT ( ). A DTI Tract-based spatial statistics (TBSS) analysis showed decreased fractional anisotropy and axial diffusivity mainly in the corticospinal tracts, cingulum, internal capsule, and external capsule at 0-6 months post-surgery (TFCE- ). The DTI metrics were not associated with the cognitive data. Processing speed impairment after an LGFLT resection can recover naturally within 3-6 months in school-age children. Rs-fMRI is more sensitive to short-term brain plasticity than DTI TBSS analysis. "Map expansion" plasticity in the frontal-basal ganglia circuit may contribute to the recovery.

Pediatric Brain Tumor Risk Associated with Head Computed Tomography: Systematic Literature Review

Computed tomography (CT) of the brain has changed diagnostic neuroradiology significantly over the past 50 years since it was firstly used back in 1971 to visualize suspected frontal lobe tumour. The safety of head CT is determined by the small amount of radiation and the low sensibility of brain tissue to cytotoxic damage due to ionizing radiation compared to other organs. However, some population groups may be at increased risk. Thus, children are more susceptible to radiation cancer than adults and lifelong attributive risk (LAR) can be more than 10 times higher for an infant than for a middle-aged adult. The authors have reviewed published studies that examined the prevalence and mortality of intracranial tumors in children undergoing head CT in comparison to unaffected individuals. Electronic search of publications in the PubMed database from 1966 to date was carried out. We have carried out intersectoral search for documents containing keywords or medical subject headings (MeSH) related to three wide categories: 1) computed tomography, 2) radiation-induced tumors, 3) risk, morbidity or epidemiology. Further search was performed in manual mode. Available epidemiological data generally confirmed correlation between head CT and tumor growth induction. Thus, current epidemiological data accept the opinion that the risk of tumor induction associated with head CT in children is very small (one tumor per 3,000–10,000 studies). The minimal estimated risk of tumor induction due to head CT in children is mostly offset by its diagnostic imaging benefits considering the clinical indications to minimize radiation dose. Understanding and quantitative risk assessment of carcinogenesis associated with CT imaging led to dose reduction in pediatric CT protocols. This trend should continue and should be implemented in all age groups. Although the decision to perform head CT is often undeniable (injury or hemorrhage), careful assessment of studies frequency is required, especially in patients who need disease monitoring. Cumulative effect in such cases may increase the minimal risk of carcinogenesis. Larger and advanced epidemiological studies are required to better understand these risks.

Toxoplasma gondii infection in patients with brain tumors in Southern Iran: a case-control study.

Considerable evidence points to a dominant role of inflammation in tumor pathology. The biological response of the immune system can be triggered by Toxoplasma gondii as a common brain-tropic parasite. The aim of this study was to investigate an association between Toxoplasma infection and brain tumors. This case-control study was performed on sera of brain tumor patients (n = 124) and age- and sex-matched control subjects (n = 124) in Southern Iran. Data related to tumor site and type were collected during sample collection. Anti-Toxoplasma IgG was assessed by enzyme-linked immunosorbent assay (ELISA). Seroprevalence anti-Toxoplasma IgG was significantly higher in brain tumor patients 30.6% (38/124) compared with 12.1% (15/124) of the healthy controls (OR 3.211; 95% CI 1.658 to 6.219; p = 0.001). The highest seroprevalence was detected in patients with ependymoma (100%), followed by glioblastoma (83%), pituitary adenoma (47.3%), astrocytoma (27.2%), schwannoma (23%), and meningioma (22.6%). The parasite infection was correlated to brain tumor's location i.e., the patients with frontal lobe and sella region tumors had higher seropositivity compared with others (P < 0.05). The higher prevalence of Toxoplasma infection among patients with brain tumor compared with the control group indicates a probable association between the infection and brain tumors.

Prognosis of overall and disease-free survival in patients with grade 3 astrocytomas (anaplastic astrocytoma, WHO 2016)

A retrospective study included 389 patients diagnosed with grade 3 astrocytoma. We analyzed dependence of overall and disease-free survival from the following factors: gender, age of onset of disease, tumor extent, surgery, neurological disorders before and after surgery (NANO grading system), Ki67 index, postoperative radio- and chemotherapy (number courses, treatment regimens). Significant risk factors for overall and disease-free survival were spread and volume of tumor, postoperative neurological aggravation, Ki67 index, IDH mutation, radio- and chemotherapy. Age, frontal lobe tumor and disease manifestation variant were significant only for overall, but not for disease-free survival. This study was based on material of one of the largest clinical series of patients with AA operated on in one center in «molecular» era. Our results are consistent with previous data. Analysis of tumor biology and risk factors for IDH-negative AA without molecular signs of glioblastoma may be perspective.