Leveraging single-cell sequencing to classify and characterize tumor subgroups in bulk RNA-sequencing data.

PURPOSE: Accurate classification of cancer subgroups is essential for precision medicine, tailoring treatments to individual patients based on their cancer subtypes. In recent years, advances in high-throughput sequencing technologies have enabled the generation of large-scale transcriptomic data from cancer samples. These data have provided opportunities for developing computational methods that can improve cancer subtyping and enable better personalized treatment strategies. METHODS: Here in this study, we evaluated different feature selection schemes in the context of meningioma classification. To integrate interpretable features from the bulk (n = 77 samples) and single-cell profiling (∼ 10 K cells), we developed an algorithm named CLIPPR which combines the top-performing single-cell models, RNA-inferred copy number variation (CNV) signals, and the initial bulk model to create a meta-model. RESULTS: While the scheme relying solely on bulk transcriptomic data showed good classification accuracy, it exhibited confusion between malignant and benign molecular classes in approximately ∼ 8% of meningioma samples. In contrast, models trained on features learned from meningioma single-cell data accurately resolved the sub-groups confused by bulk-transcriptomic data but showed limited overall accuracy. CLIPPR showed superior overall accuracy and resolved benign-malignant confusion as validated on n = 789 bulk meningioma samples gathered from multiple institutions. Finally, we showed the generalizability of our algorithm using our in-house single-cell (∼ 200 K cells) and bulk TCGA glioma data (n = 711 samples). CONCLUSION: Overall, our algorithm CLIPPR synergizes the resolution of single-cell data with the depth of bulk sequencing and enables improved cancer sub-group diagnoses and insights into their biology.

Hospital Outcomes in Patients Who Developed Acute Respiratory Distress Syndrome After Community-Acquired Pneumonia.

Purpose: To identify risk factors for and outcomes in acute respiratory distress syndrome (ARDS) in patients hospitalized with community-acquired pneumonia (CAP). Methods: This is a retrospective study using the Premier Healthcare Database between 2016 and 2020. Patients diagnosed with pneumonia, requiring mechanical ventilation (MV), antimicrobial therapy, and hospital admission ≥2 days were included. Multivariable regression models were used for outcomes including in-hospital mortality, hospital length of stay (LOS), intensive care unit (ICU) LOS, and days on MV. Results: 1924 (2.7%) of 72 107 patients with CAP developed ARDS. ARDS was associated with higher mortality (33.7% vs 18.9%; adjusted odds ratio 2.4; 95% confidence interval [CI] 2.16-2.66), longer hospital LOS (13 vs 9 days; adjusted incidence risk ratio (aIRR) 1.24; 95% CI 1.20-1.27), ICU LOS (9 vs 5 days; aIRR 1.51; 95% CI 1.46-1.56), more MV days (8 vs 5; aIRR 1.54; 95% CI 1.48-1.59), and increased hospitalization cost ($46 459 vs $29 441; aIRR 1.50; 95% CI 1.45-1.55). Conclusion: In CAP, ARDS was associated with worse in-patient outcomes in terms of mortality, LOS, and hospitalization cost. Future studies are needed to explore outcomes in patients with CAP with ARDS and explore risk factors for development of ARDS after CAP.

Evidence-Based Update on Transcatheter Therapies for Pulmonary Embolism.

PURPOSE OF REVIEW: Pulmonary embolism (PE) remains a leading cause of cardiovascular morbidity and mortality. Multiple new therapies are in development and under study to improve our contemporary care of patients with PE. We review and compare here these novel therapeutics and technologies. RECENT FINDINGS: Multiple novel therapeutic devices have been developed and are under active study. This work has advanced the care of patients with intermediate and high-risk PE. Novel therapies are improving care of complex PE patients. These have inspired large multicenter international randomized controlled trials that are actively recruiting patients to advance the care of PE. These studies will work towards advancing guidelines for clinical care of patients with PE.

Targeting GBM with an Oncolytic Picornavirus SVV-001 alone and in combination with fractionated Radiation in a Novel Panel of Orthotopic PDX models.

BACKGROUND: Animal models representing different molecular subtypes of glioblastoma multiforme (GBM) is desired for developing new therapies. SVV-001 is an oncolytic virus selectively targeting cancer cells. It's capacity of passing through the blood brain barrier makes is an attractive novel approach for GBM. MATERIALS AND METHODS: 23 patient tumor samples were implanted into the brains of NOD/SCID mice (1 × 105 cells/mouse). Tumor histology, gene expression (RNAseq), and growth rate of the developed patient-derived orthotopic xenograft (PDOX) models were compared with the originating patient tumors during serial subtransplantations. Anti-tumor activities of SVV-001 were examined in vivo; and therapeutic efficacy validated in vivo via single i.v. injection (1 × 1011 viral particle) with or without fractionated (2 Gy/day x 5 days) radiation followed by analysis of animal survival times, viral infection, and DNA damage. RESULTS: PDOX formation was confirmed in 17/23 (73.9%) GBMs while maintaining key histopathological features and diffuse invasion of the patient tumors. Using differentially expressed genes, we subclassified PDOX models into proneural, classic and mesenchymal groups. Animal survival times were inversely correlated with the implanted tumor cells. SVV-001 was active in vitro by killing primary monolayer culture (4/13 models), 3D neurospheres (7/13 models) and glioma stem cells. In 2/2 models, SVV-001 infected PDOX cells in vivo without harming normal brain cells and significantly prolonged survival times in 2/2 models. When combined with radiation, SVV-001 enhanced DNA damages and further prolonged animal survival times. CONCLUSION: A panel of 17 clinically relevant and molecularly annotated PDOX modes of GBM is developed, and SVV-001 exhibited strong anti-tumor activities in vitro and in vivo.

Integrated clinical genomic analysis reveals xenobiotic metabolic genes are downregulated in meningiomas of current smokers.

INTRODUCTION: Meningiomas are the most common primary intracranial tumor. Recently, various genetic classification systems for meningioma have been described. We sought to identify clinical drivers of different molecular changes in meningioma. As such, clinical and genomic consequences of smoking in patients with meningiomas remain unexplored. METHODS: 88 tumor samples were analyzed in this study. Whole exome sequencing (WES) was used to assess somatic mutation burden. RNA sequencing data was used to identify differentially expressed genes (DEG) and genes sets (GSEA). RESULTS: Fifty-seven patients had no history of smoking, twenty-two were past smokers, and nine were current smokers. The clinical data showed no major differences in natural history across smoking status. WES revealed absence of AKT1 mutation rate in current or past smokers compared to non-smokers (p = 0.046). Current smokers had increased mutation rate in NOTCH2 compared to past and never smokers (p < 0.05). Mutational signature from current and past smokers showed disrupted DNA mismatch repair (cosine-similarity = 0.759 and 0.783). DEG analysis revealed the xenobiotic metabolic genes UGT2A1 and UGT2A2 were both significantly downregulated in current smokers compared to past (Log2FC = - 3.97, padj = 0.0347 and Log2FC = - 4.18, padj = 0.0304) and never smokers (Log2FC = - 3.86, padj = 0.0235 and Log2FC = - 4.20, padj = 0.0149). GSEA analysis of current smokers showed downregulation of xenobiotic metabolism and enrichment for G2M checkpoint, E2F targets, and mitotic spindle compared to past and never smokers (FDR < 25% each). CONCLUSION: In this study, we conducted a comparative analysis of meningioma patients based on their smoking history, examining both their clinical trajectories and molecular changes. Meningiomas from current smokers were more likely to harbor NOTCH2 mutations, and AKT1 mutations were absent in current or past smokers. Moreover, both current and past smokers exhibited a mutational signature associated with DNA mismatch repair. Meningiomas from current smokers demonstrate downregulation of xenobiotic metabolic enzymes UGT2A1 and UGT2A2, which are downregulated in other smoking related cancers. Furthermore, current smokers exhibited downregulation xenobiotic metabolic gene sets, as well as enrichment in gene sets related to mitotic spindle, E2F targets, and G2M checkpoint, which are hallmark pathways involved in cell division and DNA replication control. In aggregate, our results demonstrate novel alterations in meningioma molecular biology in response to systemic carcinogens.

Longitudinal associations between exclusive, dual, and polytobacco use and asthma among US youth.

Little is known about the respiratory health effects of dual (two products) and polytobacco (three or more products) use among youth in the United States. Thus, we followed a longitudinal cohort of youth into adulthood using data from Waves 1-5 (2013-2019) of the Population Assessment of Tobacco and Health Study, examining incident asthma at each follow-up (Waves 2-5). We classified past 30-day tobacco use as 1) no products (never/former use), 2) exclusive cigarettes, 3) exclusive electronic nicotine delivery systems (ENDS), 4) exclusive other combustible (OC) tobacco products (cigars, hookah, pipe), 5) dual cigarettes/OC and ENDS, 6) dual cigarettes and OCs, and 7) polytobacco use (cigarettes, OCs, and ENDS). Using discrete time survival models, we analyzed the incidence of asthma across Waves 2-5, predicted by time-varying tobacco use lagged by one wave, and adjusted for potential baseline confounders. Asthma was reported by 574 of the 9141 respondents, with an average annual incidence of 1.44% (range 0.35% to 2.02%, Waves 2-5). In adjusted models, exclusive cigarette use (HR: 1.71, 95% CI: 1.11-2.64) and dual cigarette and OC use (HR: 2.78, 95% CI: 1.65-4.70) were associated with incident asthma compared to never/former use, while exclusive ENDS use (HR: 1.50, 95% CI: 0.92-2.44) and polytobacco use (HR: 1.95, 95% CI: 0.86-4.44) were not. To conclude, youth who use cigarettes with or without OCs had higher risk of incident asthma. Further longitudinal studies on the respiratory health effects of ENDS and dual/polytobacco use are needed as products continue to evolve.

Longitudinal Associations Between Exclusive and Dual Use of Electronic Nicotine Delivery Systems and Cigarettes and Self-Reported Incident Diagnosed Cardiovascular Disease Among Adults.

INTRODUCTION: The cardiovascular health effects of electronic nicotine delivery systems (ENDS) use are not well characterized, making it difficult to assess ENDS as a potential harm reduction tool for adults who use cigarettes. AIMS AND METHODS: Using waves 1-5 of the Population Assessment of Tobacco and Health Study (2013-2019), we analyzed the risk of self-reported incident diagnosed myocardial infarction (MI; 280 incident cases) and stroke (186 incident cases) associated with ENDS and/or cigarette use among adults aged 40 + using discrete time survival models. We employed a time-varying exposure lagged by one wave, defined as exclusive or dual established use of ENDS and/or cigarettes every day or some days, and controlled for demographics, clinical factors, and past smoking history. RESULTS: The analytic samples (MI = 11 031; stroke = 11 076) were predominantly female and non-Hispanic White with a mean age of 58 years. At baseline, 14.2% of respondents exclusively smoked cigarettes, 0.6% exclusively used ENDS, and 1.0% used both products. Incident MI and stroke were rare during follow-up (< 1% at each wave). Compared to no cigarette or ENDS use, exclusive cigarette use increased the risk of MI (aHR 1.99, 95% CI = 1.40-2.84) and stroke (aHR 2.26, 95% CI = 1.51-3.39), while exclusive ENDS use (MI: aHR 0.61, 95% CI = 0.12-3.04; stroke: aHR 1.74, 95% CI = 0.55-5.49) and dual use (MI: aHR 1.84, 95% CI = 0.64-5.30; stroke: aHR 1.12, 95% CI = 0.33-3.79) were not significantly associated with the risk of either outcome. CONCLUSIONS: Compared to non-use, exclusive cigarette use was associated with an increased risk of self-reported incident diagnosed cardiovascular disease over a 5-year period, while ENDS use was not associated with a statistically significant increase in the outcomes. IMPLICATIONS: Existing literature on the health effects of ENDS use has important limitations, including potential reverse causation and improper control for cigarette smoking. We accounted for these issues by using a prospective design and adjusting for current and former smoking status and cigarette pack-years. In this context, we did not find that ENDS use was associated with a statistically significant increase in self-reported incident diagnosed myocardial infarction or stroke over a 5-year period. While more studies are needed, this analysis provides an important foundation and key methodological considerations for future research on the health effects of ENDS use.

Impact of Coronavirus Disease 2019 Pandemic on Cardiac Arrest and Emergency Care.

The incidence of both out-of-hospital and in-hospital cardiac arrest increased during the coronavirus disease 2019 (COVID-19) pandemic. Patient survival and neurologic outcome after both out-of-hospital and in-hospital cardiac arrest were reduced. Direct effects of the COVID-19 illness combined with indirect effects of the pandemic on patient's behavior and health care systems contributed to these changes. Understanding the potential factors offers the opportunity to improve future response and save lives.

The effects of sport, setting, and demographics on sunscreen use and education in young athletes.

Participation in outdoor sports increases exposure to ultraviolet radiation, necessitating mitigation through sunscreen use. This prospective study examined the effects of sport, setting (practice vs. competition), gender, age and geographic location on sunscreen use and education among youth athletes in various sports. Six hundred and twelve athletes ≤18 years old completed an online survey on sunscreen education and use during competitions and practices. Regardless of sport, reported sunscreen use was higher during practices than competition (p < 0.0001). Sunscreen was used most by swimmers/divers (odds ratio: OR ≥ 1.9, p < 0.001) and least by American football players (OR ≤ 0.57, p ≤ 0.001). Coaches mentioned sunscreen use the most in track and field (OR 1.84, p = 0.001) and the least in American football (OR 0.67, p = 0.03). Athletes used sunscreen more if they were female (OR ≥ 1.9 1.38, p ≤ 0.06) and younger (age OR ≤ 0.88, p < 0.001). In conclusion, youth athletes differ in sunscreen use by sport and setting, highlighting the need for continued photoprotective education.

Waste to energy: a decision-making process for technology selection through characterization of waste, considering energy and emission in the city of Ahmedabad, India.

Municipal solid waste (MSW) disposal has become major issue for the city of Ahmedabad, India. Development, concentrated population and economic growth have led to a substantial increase of MSW generation. Therefore, the objective of the study was to characterize MSW for selection of waste processing technology. To provide a solution for sustainable processing and for safe disposal of fresh MSW, Abellon Clean Energy Ltd joined forces with Ahmedabad Municipal Corporation (AMC) under Public-Private Partnership (PPP) to establish a 14.9MW advanced controlled combustion-based waste to energy (WTE) generation facility to process and dispose 1000 tons/day of fresh MSW. For waste characterization, samples (n=201) were collected from the Pirana waste dumping site using quadrate sampling method. A yearly weighted average Low Heating Value (LHV) of 9.85/kg and ash content 25.12% for unsegregated MSW makes controlled combustion with electricity generation an eligible technology. After combustion, the waste volume is reduced by 75%. The 14.9MW WTE facility replaces 417 t coal/day, reducing greenhouse gas (GHG) emissions of 300.38 tCO2eq/day through coal replacement, while avoiding 735.24 t CO2eq/day on account of landfill emissions from MSW dumping. Waste to energy is the fastest solution to reduce waste volume by generating electricity through reduction of GHG.

XCVATR: detection and characterization of variant impact on the Embeddings of single -cell and bulk RNA-sequencing samples.

BACKGROUND: RNA-sequencing has become a standard tool for analyzing gene activity in bulk samples and at the single-cell level. By increasing sample sizes and cell counts, this technique can uncover substantial information about cellular transcriptional states. Beyond quantification of gene expression, RNA-seq can be used for detecting variants, including single nucleotide polymorphisms, small insertions/deletions, and larger variants, such as copy number variants. Notably, joint analysis of variants with cellular transcriptional states may provide insights into the impact of mutations, especially for complex and heterogeneous samples. However, this analysis is often challenging due to a prohibitively high number of variants and cells, which are difficult to summarize and visualize. Further, there is a dearth of methods that assess and summarize the association between detected variants and cellular transcriptional states. RESULTS: Here, we introduce XCVATR (eXpressed Clusters of Variant Alleles in Transcriptome pRofiles), a method that identifies variants and detects local enrichment of expressed variants within embedding of samples and cells in single-cell and bulk RNA-seq datasets. XCVATR visualizes local "clumps" of small and large-scale variants and searches for patterns of association between each variant and cellular states, as described by the coordinates of cell embedding, which can be computed independently using any type of distance metrics, such as principal component analysis or t-distributed stochastic neighbor embedding. Through simulations and analysis of real datasets, we demonstrate that XCVATR can detect enrichment of expressed variants and provide insight into the transcriptional states of cells and samples. We next sequenced 2 new single cell RNA-seq tumor samples and applied XCVATR. XCVATR revealed subtle differences in CNV impact on tumors. CONCLUSIONS: XCVATR is publicly available to download from https://github.com/harmancilab/XCVATR .

A Scoping Review on the Concept of Physician Caring.

BACKGROUND: Physicians' interest in the health and well-being of their patients is a tenet of medical practice. Physicians' ability to act upon this interest by caring for and about their patients is central to high-quality clinical medicine and may affect burnout. To date, a strong theoretical and empirical understanding of physician caring does not exist. To establish a practical, evidence-based approach to improve health care delivery and potentially address physician burnout, we sought to identify and synthesize existing conceptual models, frameworks, and definitions of physician caring. METHODS: We performed a scoping review on physician caring. In November 2019 and September 2020, we searched PubMed MEDLINE, Embase, PsycINFO, CINAHL, and CENTRAL Register of Controlled Trials to identify conceptual models, frameworks, and definitions of physician caring. Eligible articles involved discussion or study of care or caring among medical practitioners. We created a content summary and performed thematic analysis of extracted data. RESULTS: Of 11,776 articles, we reviewed the full text of 297 articles; 61 articles met inclusion criteria. Commonly identified concepts referenced Peabody's "secret of care" and the ethics of care. In bioethics, caring is described as a virtue. Contradictions exist among concepts of caring, such as whether caring is an attitude, emotion, or behavior, and the role of relationship development. Thematic analysis of all concepts and definitions identified six aspects of physician caring: (1) relational aspects, (2) technical aspects, (3) physician attitudes and characteristics, (4) agency, (5) reciprocity, and (6) physician self-care. DISCUSSION: Caring is instrumental to clinical medicine. However, scientific understanding of what constitutes caring from physicians is limited by contradictions across concepts. A unifying concept of physician caring does not yet exist. This review proposes six aspects of physician caring which can be used to develop evidence-based approaches to improve health care delivery and potentially mitigate physician burnout.

A longitudinal study of menthol cigarette use and smoking cessation among adult smokers in the US: Assessing the roles of racial disparities and E-cigarette use.

Using nationally representative longitudinal data from Wave 1 to Wave 4 of the Population Assessment of Tobacco and Health Study in the United States, we examined whether the association between menthol cigarette use and smoking cessation was modified by race/ethnicity and e-cigarette use. Multivariable discrete-time survival models were fit to an unbalanced person-period data set (person n = 7423, risk period n = 18,897) for adult respondents (ages 25+) who were current established cigarette smokers at baseline. We found that adults who smoke menthol cigarettes had lower odds of smoking cessation, but the effect was modified by race/ethnicity as non-Hispanic (NH) Black menthol smokers had lower odds of quitting smoking than NH White or Hispanic menthol smokers. We also found that e-cigarette use was associated with higher odds of smoking cessation among both menthol and non-menthol smokers, but the association was stronger among menthol smokers. Our results suggest that a menthol smoking ban may have a favorable impact on smoking cessation for NH Black adults. In addition, our results also suggest that a menthol smoking ban may be more effective if menthol smokers have access to e-cigarettes as a way to quit cigarette use.

Low-voltage area substrate modification for atrial fibrillation ablation: a systematic review and meta-analysis of clinical trials.

AIMS: The value of additional ablation beyond pulmonary vein isolation for atrial fibrillation (AF) ablation is unclear, especially for persistent AF. The optimal target for substrate modification to improve outcomes is uncertain. We investigate the utility of low-voltage area (LVA) substrate modification in patients undergoing catheter ablation for AF. METHODS AND RESULTS: This meta-analysis was reported according to the Preferred Reporting Items for Systematic Review and Meta-Analyses guidelines. Medline, Scopus and Cochrane Central Register of Controlled Trials were systematically searched to identify relevant studies. Risk of bias was assessed using the Cochrane risk of bias tool. Only randomized studies were included. AF patients who underwent catheter ablation with voltage-guided substrate modification targeting LVA (LVA group) vs. conventional ablation approaches not targeting LVA (non-LVA group) were compared. Four studies comprising 539 patients were included (36% female). Freedom from arrhythmia (FFA) in patients with persistent AF was greater in the LVA group [risk ratio (RR) 1.30; 95% confidence interval (CI) 1.03-1.64]. There was no difference in FFA in patients with paroxysmal AF between groups (RR 1.30; 95% CI 0.89-1.91). There was no difference in total procedural time (mean difference -17.54 min; 95% CI -64.37 to 29.28 min) or total ablation time (mean difference -36.17 min; 95% CI -93.69 to 21.35 min) in all included patients regardless of AF type between groups. There was no difference in periprocedural complications between groups in all included patients regardless of AF type (RR 0.93; 95% CI 0.22-3.82). CONCLUSION: This meta-analysis demonstrates improved FFA in persistent AF patients who underwent voltage-guided substrate modification targeting LVA.

Innate immunity stimulation via CpG oligodeoxynucleotides ameliorates Alzheimer's disease pathology in aged squirrel monkeys.

Alzheimer's disease is the most common cause of dementia and the only illness among the top 10 causes of death for which there is no disease-modifying therapy. The failure rate of clinical trials is very high, in part due to the premature translation of successful results in transgenic mouse models to patients. Extensive evidence suggests that dysregulation of innate immunity and microglia/macrophages plays a key role in Alzheimer's disease pathogenesis. Activated resident microglia and peripheral macrophages can display protective or detrimental phenotypes depending on the stimulus and environment. Toll-like receptors (TLRs) are a family of innate immune regulators known to play an important role in governing the phenotypic status of microglia. We have shown in multiple transgenic Alzheimer's disease mouse models that harnessing innate immunity via TLR9 agonist CpG oligodeoxynucleotides (ODNs) modulates age-related defects associated with immune cells and safely reduces amyloid plaques, oligomeric amyloid-ß, tau pathology, and cerebral amyloid angiopathy (CAA) while promoting cognitive benefits. In the current study we have used a non-human primate model of sporadic Alzheimer's disease pathology that develops extensive CAA-elderly squirrel monkeys. The major complications in current immunotherapeutic trials for Alzheimer's disease are amyloid-related imaging abnormalities, which are linked to the presence and extent of CAA; hence, the prominence of CAA in elderly squirrel monkeys makes them a valuable model for studying the safety of the CpG ODN-based concept of immunomodulation. We demonstrate that long-term use of Class B CpG ODN 2006 induces a favourable degree of innate immunity stimulation without producing excessive or sustained inflammation, resulting in efficient amelioration of both CAA and tau Alzheimer's disease-related pathologies in association with behavioural improvements and in the absence of microhaemorrhages in aged elderly squirrel monkeys. CpG ODN 2006 has been well established in numerous human trials for a variety of diseases. The present evidence together with our earlier, extensive preclinical research, validates the beneficial therapeutic outcomes and safety of this innovative immunomodulatory approach, increasing the likelihood of CpG ODN therapeutic efficacy in future clinical trials.

Gabapentinoid Use in Perioperative Care and Current Controversies.

PURPOSE OF REVIEW: This review summarizes the risks and benefits of gabapentinoids (gabapentin and pregabalin) for perioperative pain control and the controversies surrounding their use in a variety of settings. We review current literature with the goal of providing patient-centric and procedure-specific recommendations for the use of these medications. RECENT FINDINGS: Gabapentinoids are among the most prescribed medications in the USA, and typically for off-label indications such as postoperative pain. In the perioperative setting, multimodal analgesic or "opioid-sparing" regimens have become the standard of care-and some clinical protocols include gabapentinoids. At the same time, guidelines regarding the perioperative use of gabapentinoids are conflicting and evidence supporting their broad use is lacking. Gabapentinoids administered perioperatively reduce opioid requirements and pain scores for a variety of surgeries. The extent of opioid and pain reduction, however, is not always clinically significant. These medications reduce postoperative nausea and vomiting as well as pruritis, likely as a feature of reducing opioid intake, but are associated with side effects such as dizziness, ataxia, and cognitive dysfunction. Gabapentinoids also increase the risk of respiratory depression, in particular when paired with opioids. There is thus evidence suggesting that the routine use of these medications for perioperative pain management is not recommended. An individualized, patient- and surgery-specific approach should be used, although research is still needed to determine risks and benefits during perioperative use.

Molecular profiling predicts meningioma recurrence and reveals loss of DREAM complex repression in aggressive tumors.

Meningiomas account for one-third of all primary brain tumors. Although typically benign, about 20% of meningiomas are aggressive, and despite the rigor of the current histopathological classification system there remains considerable uncertainty in predicting tumor behavior. Here, we analyzed 160 tumors from all 3 World Health Organization (WHO) grades (I through III) using clinical, gene expression, and sequencing data. Unsupervised clustering analysis identified 3 molecular types (A, B, and C) that reliably predicted recurrence. These groups did not directly correlate with the WHO grading system, which classifies more than half of the tumors in the most aggressive molecular type as benign. Transcriptional and biochemical analyses revealed that aggressive meningiomas involve loss of the repressor function of the DREAM complex, which results in cell-cycle activation; only tumors in this category tend to recur after full resection. These findings should improve our ability to predict recurrence and develop targeted treatments for these clinically challenging tumors.

Predicting surgical decision-making in vestibular schwannoma using tree-based machine learning.

OBJECTIVE: Vestibular schwannomas (VSs) are the most common neoplasm of the cerebellopontine angle in adults. Though these lesions are generally slow growing, their growth patterns and associated symptoms can be unpredictable, which may complicate the decision to pursue conservative management versus active intervention. Additionally, surgical decision-making can be controversial because of limited high-quality evidence and multiple quality-of-life considerations. Machine learning (ML) is a powerful tool that utilizes data sets to essentialize multidimensional clinical processes. In this study, the authors trained multiple tree-based ML algorithms to predict the decision for active treatment versus MRI surveillance of VS in a single institutional cohort. In doing so, they sought to assess which preoperative variables carried the most weight in driving the decision for intervention and could be used to guide future surgical decision-making through an evidence-based approach. METHODS: The authors reviewed the records of patients who had undergone evaluation by neurosurgery and otolaryngology with subsequent active treatment (resection or radiation) for unilateral VS in the period from 2009 to 2021, as well as those of patients who had been evaluated for VS and were managed conservatively throughout 2021. Clinical presentation, radiographic data, and management plans were abstracted from each patient record from the time of first evaluation until the last follow-up or surgery. Each encounter with the patient was treated as an instance involving a management decision that depended on demographics, symptoms, and tumor profile. Decision tree and random forest classifiers were trained and tested to predict the decision for treatment versus imaging surveillance on the basis of unseen data using an 80/20 pseudorandom split. Predictor variables were tuned to maximize performance based on lowest Gini impurity indices. Model performance was optimized using fivefold cross-validation. RESULTS: One hundred twenty-four patients with 198 rendered decisions concerning management were included in the study. In the decision tree analysis, only a maximum tumor dimension threshold of 1.6 cm and progressive symptoms were required to predict the decision for treatment with 85% accuracy. Optimizing maximum dimension thresholds and including age at presentation boosted accuracy to 88%. Random forest analysis (n = 500 trees) predicted the decision for treatment with 80% accuracy. Factors with the highest variable importance based on multiple measures of importance, including mean minimal conditional depth and largest Gini impurity reduction, were maximum tumor dimension, age at presentation, Koos grade, and progressive symptoms at presentation. CONCLUSIONS: Tree-based ML was used to predict which factors drive the decision for active treatment of VS with 80%-88% accuracy. The most important factors were maximum tumor dimension, age at presentation, Koos grade, and progressive symptoms. These results can assist in surgical decision-making and patient counseling. They also demonstrate the power of ML algorithms in extracting useful insights from limited data sets.

Varied histomorphology and clinical outcomes of FGFR3-TACC3 fusion gliomas.

Targeted therapies for driver gene fusions in cancers have yielded substantial improvements in care. Here, the authors outline a case series of 6 patients with FGFR3-TACC3 fusion in primary brain tumors ranging from polymorphous low-grade neuroepithelial tumor of the young to papillary glioneuronal tumors and glioblastoma (GBM). Previous studies indicated the FGFR3-TACC3 fusion provides survival benefit to GBM patients. Consistent with this, 2 patients with GBM had unexpectedly good outcomes and survived for 5 and 7 years, respectively. In contrast, 2 patients with initially lower graded tumors survived only 3 years and 1 year, respectively. One patient received erdafitinib, a targeted FGFR inhibitor, for 3 months at late disease recurrence and no response was seen. There were varied histomorphological features, including many cases that lacked the characteristic FGFR3-TACC3 pathology. The findings of this cohort suggest that molecular testing is justified, even for glioma cases lacking classic histopathological signatures. Currently, FGFR3-TACC3 fusion gliomas are often classified on the basis of histopathological features. However, further research is needed to examine whether IDH1/2-wild-type tumors with FGFR3-TACC3 fusion should be classified as a subtype on the basis of this molecular fusion. Because patients with IDH1/2-wild-type GBM with FGFR3-TACC3 fusion have improved survival, routine molecular testing for this mutation in patients enrolled in clinical trials and subsequent stratification may be warranted.

Low-Fidelity Arthroscopic Simulation Training in Trauma and Orthopaedic Surgery: A Systematic Review of Experimental Studies.

PURPOSE: To identify and appraise evidence assessing the effectiveness of low-fidelity arthroscopic simulation in the acquisition of arthroscopic surgical skills in a novice population. METHODS: Four databases were electronically searched in accordance with the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) algorithm. Studies from any year that described the use of orthopaedic, low-fidelity arthroscopic training models in novice populations were included. Questionnaires, case studies, and review studies were excluded. Risk of bias assessment was conducted using the Cochrane Collaboration's Risk of Bias Tool or the Cochrane Risk of Bias in Non-Randomised Studies of Interventions (ROBINS-I) checklist. RESULTS: Sixteen studies were identified. Using the PRISMA algorithm, 6 studies were included with a total of 131 novice participants. Individual studies ranged from 8 to 40 novices and were of Level I to II evidence. Outcome measurements varied between studies (total 16 different outcomes used). Various outcome measures used for assessing arthroscopic surgical skills within all 6 studies demonstrated significant improvement. A cross-study subjective outcome synthesis revealed low-fidelity arthroscopic simulators reduced time to completion outcomes (2 studies, P < .05), increased Arthroscopic Surgical Skill Evaluation Tool scores (2 studies, P < .01), and confirmed face validity (2 studies) and transfer of skills to cadavers (2 studies) or live patients (1 study). Cost data were under-reported in all studies apart from one. CONCLUSIONS: Arthroscopic training using low-fidelity simulators likely improves the performance of novice participants in completing basic arthroscopic procedures. These simulators may also be more cost effective and thus more implementable than their high-fidelity counterparts. LEVEL OF EVIDENCE: Level II, systematic review of Level I-II studies.