Meningioma: International Consortium on Meningiomas (ICOM) consensus review on scientific advances & treatment paradigms for clinicians, researchers, and patients.

Meningiomas are the most common primary intracranial tumors in adults and are increasing in incidence due to the aging population and the rising availability of neuroimaging. While most exhibit non-malignant behaviour, a subset of meningiomas are biologically aggressive and lead to significant neurological morbidity and mortality. In recent years, meaningful advances in our understanding of the biology of these tumors have led to the incorporation of molecular biomarkers into their grading and prognostication. However, unlike other central nervous system tumors, a unified molecular taxonomy for meningiomas has not yet been established and remains an overarching goal of the Consortium to Inform Molecular and Practical Approaches to CNS Tumor Taxonomy-Not Official WHO (cIMPACT-NOW) working group. There also remains clinical equipoise on how specific meningioma cases and patient populations should be optimally managed. To address these existing gaps, members of the International Consortium on Meningiomas (ICOM) including field-leading experts, have prepared a comprehensive consensus narrative review directed towards clinicians, researchers, and patients. Included in this manuscript are detailed overviews of proposed molecular classifications, novel biomarkers, contemporary treatment strategies, trials on systemic therapies, health-related quality of life studies, and management strategies for unique meningioma patient populations. In each section we discuss the current state of knowledge as well as ongoing clinical and research challenges to road map future directions for further investigation.

Oncolytic DNX-2401 virotherapy plus pembrolizumab in recurrent glioblastoma: a phase 1/2 trial.

Immune-mediated anti-tumoral responses, elicited by oncolytic viruses and augmented with checkpoint inhibition, may be an effective treatment approach for glioblastoma. Here in this multicenter phase 1/2 study we evaluated the combination of intratumoral delivery of oncolytic virus DNX-2401 followed by intravenous anti-PD-1 antibody pembrolizumab in recurrent glioblastoma, first in a dose-escalation and then in a dose-expansion phase, in 49 patients. The primary endpoints were overall safety and objective response rate. The primary safety endpoint was met, whereas the primary efficacy endpoint was not met. There were no dose-limiting toxicities, and full dose combined treatment was well tolerated. The objective response rate was 10.4% (90% confidence interval (CI) 4.2-20.7%), which was not statistically greater than the prespecified control rate of 5%. The secondary endpoint of overall survival at 12 months was 52.7% (95% CI 40.1-69.2%), which was statistically greater than the prespecified control rate of 20%. Median overall survival was 12.5 months (10.7-13.5 months). Objective responses led to longer survival (hazard ratio 0.20, 95% CI 0.05-0.87). A total of 56.2% (95% CI 41.1-70.5%) of patients had a clinical benefit defined as stable disease or better. Three patients completed treatment with durable responses and remain alive at 45, 48 and 60 months. Exploratory mutational, gene-expression and immunophenotypic analyses revealed that the balance between immune cell infiltration and expression of checkpoint inhibitors may potentially inform on response to treatment and mechanisms of resistance. Overall, the combination of intratumoral DNX-2401 followed by pembrolizumab was safe with notable survival benefit in select patients (ClinicalTrials.gov registration: NCT02798406).

Increased mRNA expression of CDKN2A is a transcriptomic marker of clinically aggressive meningiomas.

Homozygous deletion of CDKN2A/B was recently incorporated into the World Health Organization classification for grade 3 meningiomas. While this marker is overall rare in meningiomas, its relationship to other CDKN2A alterations on a transcriptomic, epigenomic, and copy number level has not yet been determined. We therefore utilized multidimensional molecular data of 1577 meningioma samples from 6 independent cohorts enriched for clinically aggressive meningiomas to comprehensively interrogate the spectrum of CDKN2A alterations through DNA methylation, copy number variation, transcriptomics, and proteomics using an integrated molecular approach. Homozygous CDKN2A/B deletions were identified in only 7.1% of cases but were associated with significantly poorer outcomes compared to tumors without these deletions. Heterozygous CDKN2A/B deletions were identified in 2.6% of cases and had similarly poor outcomes as those with homozygous deletions. Among tumors with intact CDKN2A/B (without a homozygous or heterozygous deletion), we found a distinct difference in outcome based on mRNA expression of CDKN2A, with meningiomas that had elevated mRNA expression (CDKN2Ahigh) having a significantly shorter time to recurrence. The expression of CDKN2A was independently prognostic after accounting for copy number loss and consistently increased with WHO grade and more aggressive molecular and methylation groups irrespective of cohort. Despite the discordant and mutually exclusive status of the CDKN2A gene in these groups, both CDKN2Ahigh meningiomas and meningiomas with CDKN2A deletions were enriched for similar cell cycle pathways but at different checkpoints. High mRNA expression of CDKN2A was also associated with gene hypermethylation, Rb-deficiency, and lack of response to CDK inhibition. p16 immunohistochemistry could not reliably differentiate between meningiomas with and without CDKN2A deletions but appeared to correlate better with mRNA expression. These findings support the role of CDKN2A mRNA expression as a biomarker of clinically aggressive meningiomas with potential therapeutic implications.

Current Trends in Neurosurgical Management of Adult Diffuse Low-Grade Gliomas in Canada.

There is considerable variability in the management of diffuse low-grade gliomas (LGGs). To characterize treatment paradigms, a survey of Canadian neurosurgeons was performed with forty neurosurgeons responding. Their responses show that the management of patients with LGGs has evolved in the past decade and findings from the RTOG9802 trial have been integrated into the practice of Canadian neurosurgeons. Most respondents stated that the patient selection and treatment strategy advocated by the RTOG9802 trial needs further evaluation. Overall, there is a trend toward more aggressive surgical resections, and future investigations will have to more accurately stratify patient risk profiles.

Shoulder Rotation Function Following the Sup-ER Protocol in Children with Brachial Plexus Injuries.

Background: Our group previously developed an upper extremity repositioning (Sup-ER) protocol for brachial plexus birth injuries (BPBIs) that may improve supination and external rotation (ER) at 2 years of age. Questions were raised about the potential for the protocol to cause internal rotation (IR) deficits. The goal of this study was to explore the longer-term outcomes of the Sup-ER protocol and investigate IR/ER function. Methods: This prospective cross-sectional cohort study examined 16 children older than 4 years of age with significant enough BPBI to be treated with the Sup-ER protocol. Total shoulder and elbow function were assessed, including passive and active ranges of motion and strength of IR and ER. Results: Range of motion (ROM) for most active movements was decreased in the affected compared to unaffected arm. Notably, IR passive ROM was similar in the affected (78.7°) and unaffected arm (82.8°). External rotation strength of the affected arm was weaker (42.8 N) compared to the unaffected arm (57.9 N). IR strength had a greater deficit in the affected (43.2 N) arm compared to the unaffected arm (72.2 N), but both ER and IR showed less deficit than described in the literature. Conclusions: Despite differences in ranges of motion between the affected and unaffected arms, ROMs for the affected arm were comparable to the functional limits as reported in the literature. The Sup-ER protocol shows potential to optimize long-term shoulder rotation function in children with BPBI without compromising IR.

Sex differences in surgically correctable congenital anomalies: A systematic review.

PURPOSE: This study aims to compare the prevalence and outcomes of surgically correctable congenital anomalies between sexes. METHODS: Upon registration on PROSPERO (CRD42019120165), a librarian aided in conducting a systematic review using PRISMA guidelines. The five largest relevant studies were included for each anomaly. Cumulative prevalence differences and confidence intervals were calculated, and the Cochran-Mantel-Haenszel test was performed. RESULTS: Of 42,722 identified studies, 68 were included in our analysis. All included anomalies had greater than 1000 patients except duodenal atresia (n = 787) and intestinal duplication (n = 148). Males had a significantly higher prevalence than females in 10/14 anomalies (Hirschsprung's disease, omphalomesenteric duct, congenital diaphragmatic hernia, anorectal malformation, malrotation, esophageal atresia, congenital pulmonary airway malformation, intestinal atresia, omphalocele, and gastroschisis; p < 0.001). There was no difference in the prevalence of duodenal atresia or intestinal duplication between sexes (p = 0.88 and 0.65, respectively). Females had a significantly higher prevalence of biliary anomalies (atresia and choledochal cyst). CONCLUSION: Our study indicates that males have higher prevalence rates of most congenital anomalies. Further investigations are required to illuminate the embryology underlying this sex distribution and whether sex influences outcomes. TYPE OF STUDY: Systematic review and meta-analysis. LEVEL OF EVIDENCE: Prognostic study, level II.

Coagulation factor XIIIa cross-links amyloid ß into dimers and oligomers and to blood proteins.

In cerebral amyloid angiopathy (CAA) and Alzheimer's disease (AD), the amyloid ß (Aß) peptide deposits along the vascular lumen, leading to degeneration and dysfunction of surrounding tissues. Activated coagulation factor XIIIa (FXIIIa) covalently cross-links proteins in blood and vasculature, such as in blood clots and on the extracellular matrix. Although FXIIIa co-localizes with Aß in CAA, the ability of FXIIIa to cross-link Aß has not been demonstrated. Using Western blotting, kinetic assays, and microfluidic analyses, we show that FXIIIa covalently cross-links Aß40 into dimers and oligomers (kcat/Km = 1.5 × 105 m-1s-1), as well as to fibrin, platelet proteins, and blood clots under flow in vitro Aß40 also increased the stiffness of platelet-rich plasma clots in the presence of FXIIIa. These results suggest that FXIIIa-mediated cross-linking may contribute to the formation of Aß deposits in CAA and Alzheimer's disease.