Integrating Ataxia Evaluation into Tumor-Induced Hearing Loss Model to Comprehensively Study NF2-Related Schwannomatosis.

NF2-related Schwannomatosis (NF2-SWN) is a disease that needs new solutions. The hallmark of NF2-SWN, a dominantly inherited neoplasia syndrome, is bilateral vestibular schwannomas (VSs), which progressively enlarge, leading to sensorineural hearing loss, tinnitus, facial weakness, and pain that translates to social impairment and clinical depression. Standard treatments for growing VSs include surgery and radiation therapy (RT); however, both carry the risk of further nerve damage that can result in deafness and facial palsy. The resultant suffering and debility, in combination with the paucity of therapeutic options, make the effective treatment of NF2-SWN a major unmet medical need. A better understanding of these mechanisms is essential to developing novel therapeutic targets to control tumor growth and improve patients' quality of life. Previously, we developed the first orthotopic cerebellopontine angle mouse model of VSs, which faithfully mimics tumor-induced hearing loss. In this model, we observed that mice exhibit symptoms of ataxia and vestibular dysfunction. Therefore, we further developed a panel of five tests suitable for the mouse VS model and investigated how tumor growth and treatment affect gait, coordination, and motor function. Using this panel of ataxia tests, we demonstrated that both ataxia and motor function deteriorated concomitantly with tumor progression. We further demonstrated that (i) treatment with anti-VEGF resulted in tumor size reduction, mitigated ataxia, and improved rotarod performance; (ii) treatment with crizotinib stabilized tumor growth and led to improvements in both ataxia and rotarod performance; and (iii) treatment with losartan did not impact tumor growth nor ameliorate ataxia or motor function. Our studies demonstrated that these methods, paired with hearing tests, enable a comprehensive evaluation of tumor-induced neurological deficits and facilitate the assessment of the effectiveness of novel therapeutics to improve NF2 treatments.

Rapid Tumor DNA Analysis of Cerebrospinal Fluid Accelerates Treatment of Central Nervous System Lymphoma.

Delays and risks associated with neurosurgical biopsies preclude timely diagnosis and treatment of central nervous system (CNS) lymphoma and other CNS neoplasms. We prospectively integrated targeted rapid genotyping of cerebrospinal fluid (CSF) into the evaluation of 70 patients with CNS lesions of unknown etiology. Participants underwent genotyping of CSF-derived DNA using a qPCR-based approach for parallel detection of single-nucleotide variants in the MYD88, TERT promoter, IDH1, IDH2, BRAF and H3F3A genes within 80 minutes of sample acquisition. Canonical mutations were detected in 42% of patients with neoplasms, including cases of primary and secondary CNS lymphoma, glioblastoma, IDH-mutant brainstem glioma and H3K27M-mutant diffuse midline glioma. Genotyping results eliminated the need for surgical biopsies in 7/33 (21.2%) cases of newly diagnosed neoplasms, resulting in significantly accelerated initiation of disease-directed treatment (median 3 vs 12 days; p = 0.027). This assay was then implemented in a Clinical Laboratory Improvement Amendments (CLIA) environment, with 2-day median turnaround for diagnosis of central nervous system lymphoma from 66 patients across 4 clinical sites. Our study prospectively demonstrates that targeted rapid CSF genotyping influences oncologic management for suspected CNS tumors.

Perioperative anaphylaxis: updates on pathophysiology.

PURPOSE OF REVIEW: Perioperative anaphylaxis has historically been attributed to IgE/FcεRI-mediated reactions; there is now recognition of allergic and nonallergic triggers encompassing various reactions beyond IgE-mediated responses. This review aims to present recent advancements in knowledge regarding the mechanisms and pathophysiology of perioperative anaphylaxis. RECENT FINDINGS: Emerging evidence highlights the role of the mast-cell related G-coupled protein receptor X2 pathway in direct mast cell degranulation, shedding light on previously unknown mechanisms. This pathway, alongside traditional IgE/FcεRI-mediated reactions, contributes to the complex nature of anaphylactic reactions. Investigations into the microbiota-anaphylaxis connection are ongoing, with potential implications for future treatment strategies. While serum tryptase levels serve as mast cell activation indicators, identifying triggers remains challenging. A range of mediators have been associated with anaphylaxis, including vasoactive peptides, proteases, lipid molecules, cytokines, chemokines, interleukins, complement components, and coagulation factors. SUMMARY: Further understanding of clinical endotypes and the microenvironment where anaphylactic reactions unfold is essential for standardizing mediator testing and characterization in perioperative anaphylaxis. Ongoing research aims to elucidate the mechanisms, pathways, and mediators involved across multiple organ systems, including the cardiovascular, respiratory, and integumentary systems, which will be crucial for improving patient outcomes.

Histologic correlates of "Choroidal abnormalities" in Neurofibromatosis type 1 (NF1).

Neurofibromatosis type 1 (NF1) is a rare autosomal dominant disorder characterized by proliferation of cells from neural crest origin. The most common manifestations are cutaneous, neurologic, skeletal and ocular. The distinction of NF1 from other syndromes with multiple café-au-lait macules may be difficult in the pediatric age group, and ocular findings, especially Lisch nodules (i.e., melanocytic hamartomas on the irides), are a useful, early diagnostic tool. In recent years, novel ocular manifestations descriptively referred to as "choroidal abnormalities", choroidal "hyperpigmented spots" and "retinal vascular abnormalities" have been recognized in NF1. Choroidal abnormalities (CA) appear as bright patchy nodules that can be best detected with near-infrared ocular coherence tomography imaging (NIR-OCT). Because of their high specificity and sensitivity for NF1, CA have been added as an ocular diagnostic criterion of NF1 as an alternative to Lisch nodules. Although CA are important ocular diagnostic criteria for NF1, the histologic correlates are controversial. We present the postmortem ocular pathology findings of an NF1 patient for whom clinical notes and ocular imaging were available. Findings in this patient included choroidal hyperpigmented spots on funduscopy and retinal vascular abnormalities, both of which have been reported to be closely associated with CA. Histologic examination of the eyes showed multiple clusters of melanocytes of varying sizes in the choroid. Pathologic review of 12 additional postmortem eyes from 6 NF1 patients showed multiple, bilateral choroidal melanocytic aggregates in all eyes. These findings suggest that the CA seen on NIR-OCT and the hyperpigmented spots seen clinically in NF1 patients are manifestations of multifocal choroidal melanocytic clusters, consistent with choroidal melanocytic hamartomas. Lisch nodules, often multiple, were present in all eyes with morphology that differed from the choroidal hamartomas. As such, although CA and Lisch nodules are melanocytic hamartomas, there are clear phenotypical differences in their morphologies.

Prescription Drug Prices: An AAN Position Statement.

This position statement serves to establish the AAN's stance on the methods to address the cost of prescription drugs being considered by state and federal policymakers so that the AAN can continue to advocate effectively for its members. Neurologists seek to provide high-value care for patients with neurologic diseases at the lowest cost possible. However, many therapies for neurologic diseases are among the most expensive in the United States. The 3 major cost challenges include (1) unjustified increases in the pricing for drugs used to treat neurologic disorders, (2) the high cost of medications used to treat rare diseases where there are limited or no therapeutic options available, and (3) the high cost of noninnovative (already FDA-approved) therapies that used accelerated FDA approval pathways or Orphan Drug Act designated to expedite approvals in neurologic disorders. In each of these cases, AAN is concerned that the high cost does not deliver sufficient value to patients or society. The AAN's position is that action must be taken to ensure that effective prescription medications are accessible for patients with complex, chronic neurologic conditions. Potential solutions should be affordable, simple, and transparent. Cost-containment efforts must also address the burden on the entire healthcare system because high prescription drug prices may be shifted and absorbed in ways that negatively affect patient and prescriber access to important medications. AAN supports price negotiations, the cost saving potential of generics and biosimilars, development of novel therapeutics, price transparency, and importation.

Noninvasive treatment of cutaneous neurofibromas (cNFs): Results of a randomized prospective, direct comparison of four methods.

BACKGROUND: People with Neurofibromatosis Type 1 (NF1) suffer disfigurement and pain when hundreds to thousands of cutaneous neurofibromas (cNFs) appear and grow throughout life. Surgical removal of cNFs under anesthesia is the only standard therapy, leaving surgical scars. OBJECTIVE: Effective, minimally-invasive, safe, rapid, tolerable treatment(s) of small cNFs that may prevent tumor progression. METHODS: Safety, tolerability, and efficacy of 4 different treatments were compared in 309, 2-4 mm cNFs across 19 adults with Fitzpatrick skin types (FST) I-IV: radiofrequency (RF) needle coagulation, 755 nm alexandrite laser with suction, 980 nm diode laser, and intratumoral injection of 10 mg/mL deoxycholate. Regional pain, clinical responses, tumor height and volume (by 3D photography) were assessed before, 3 and 6 months post-treatment. Biopsies were obtained electively at 3 months. RESULTS: There was no scarring or adverse events > grade 2. Each modality significantly (P < .05) reduced or cleared cNFs, with large variation between tumors and participants. Alexandrite laser and deoxycholate were fast and least painful; 980 nm laser was most painful. Growth of cNFs was not stimulated by treatment(s) based on height and volume values at 3 and 6 months compared to baseline. LIMITATIONS: Intervention was a single treatment session; dosimetry has not been optimized. CONCLUSIONS: Small cNFs can be rapidly and safely treated without surgery.

The Brain Health Imperative in the 21st Century-A Call to Action: The AAN Brain Health Platform and Position Statement.

Brain health is crucial to optimizing both the function and well-being of every person at each stage of life and is key to both individual and social progress. As a concept, brain health is complex and requires a multidisciplinary collaborative approach between many professional and public organizations to bring into effect meaningful change. Neurologists are uniquely positioned to serve as specialists in brain health and to advance the newly evolving field of preventive neurology, which aims to identify individuals at high risk of brain disorders and other neurologic conditions and offer strategies to mitigate disease emergence or progression. For decades, the American Academy of Neurology (AAN) has demonstrated a commitment to brain health through its public outreach and advocacy. The AAN's Brain Health Initiative launched in 2022 with a strategic plan prioritizing brain health as a key aspect of public engagement and positioning the AAN and neurologists as champions of brain health in collaboration with a broad range of other brain health providers. In this study, we present (1) the new definition of brain health developed by the AAN for neurologists, patients, partners in health care, and the public; (2) the strategic objectives of the AAN Brain Health Initiative; and (3) the AAN Brain Health Platform and Action Plan framework, including key positions on brain health, its 3 ambitious goals, and a national brain health vision. The top-line priorities of the AAN Brain Health Action Plan highlight the need for research, education, public policy, and direct-to-public messaging across the individual's life span and will serve as a catalyst for future cross-disciplinary collaborations within each epoch and longitudinally. The AAN Brain Health Platform is designed to communicate the AAN's vision for brain health and provide a blueprint toward achieving the future of optimal brain health across the life span for all. Through this position statement, we call upon neurologists and other stakeholders in brain health to join our collective efforts to accomplish the ultimate goal of transforming the current trajectory of public health of an increasing burden of neurologic disorders-from both illness and injury-to achieving optimal brain health for all.

Neurotoxicity and management of primary and secondary central nervous system lymphoma after adoptive immunotherapy with CD19-directed chimeric antigen receptor T-cells.

BACKGROUND: Chimeric antigen receptor (CAR) T-cells targeting CD19 have been established as a leading engineered T-cell therapy for B-cell lymphomas; however, data for patients with central nervous system (CNS) involvement are limited. METHODS: We retrospectively report on CNS-specific toxicities, management, and CNS response of 45 consecutive CAR T-cell transfusions for patients with active CNS lymphoma at the Massachusetts General Hospital over a 5-year period. RESULTS: Our cohort includes 17 patients with primary CNS lymphoma (PCNSL; 1 patient with 2 CAR T-cell transfusions) and 27 patients with secondary CNS lymphoma (SCNSL). Mild ICANS (grade 1-2) was observed after 19/45 transfusions (42.2%) and severe immune effector cell-associated neurotoxicity syndrome (ICANS) (grade 3-4) after 7/45 transfusions (15.6%). A larger increase in C-reactive protein (CRP) levels and higher rates of ICANS were detected in SCNSL. Early fever and baseline C-reactive protein levels were associated with ICANS occurrence. CNS response was seen in 31 cases (68.9%), including a complete response of CNS disease in 18 cases (40.0%) which lasted for a median of 11.4 ±â€…4.5 months. Dexamethasone dose at time of lymphodepletion (but not at or after CAR T-cell transfusion) was associated with an increased risk for CNS progression (hazard ratios [HR] per mg/d: 1.16, P = .031). If bridging therapy was warranted, the use of ibrutinib translated into favorable CNS-progression-free survival (5 vs. 1 month, HR 0.28, CI 0.1-0.7; P = .010). CONCLUSIONS: CAR T-cells exhibit promising antitumor effects and a favorable safety profile in CNS lymphoma. Further evaluation of the role of bridging regimens and corticosteroids is warranted.

Effect of Mind-Body Skills Training on Quality of Life for Geographically Diverse Adults With Neurofibromatosis: A Fully Remote Randomized Clinical Trial.

Importance: Neurofibromatoses (NF; NF1, NF2, and schwannomatosis) are hereditary tumor predisposition syndromes with a risk for poor quality of life (QOL) and no evidence-based treatments. Objective: To compare a mind-body skills training program, the Relaxation Response Resiliency Program for NF (3RP-NF), with a health education program (Health Enhancement Program for NF; HEP-NF) for improvement of quality of life among adults with NF. Design, Setting, and Participants: This single-blind, remote randomized clinical trial randomly assigned 228 English-speaking adults with NF from around the world on a 1:1 basis, stratified by NF type, between October 1, 2017, and January 31, 2021, with the last follow-up February 28, 2022. Interventions: Eight 90-minute group virtual sessions of 3RP-NF or HEP-NF. Main Outcomes and Measures: Outcomes were collected at baseline, after treatment, and at 6-month and 1-year follow-up. The primary outcomes were physical health and psychological domain scores of the World Health Organization Quality of Life Brief Version (WHOQOL-BREF). Secondary outcomes were the social relationships and environment domain scores of the WHOQOL-BREF. Scores are reported as transformed domain scores (range, 0-100, with higher scores indicating higher QOL). Analysis was performed on an intention-to-treat basis. Results: Of 371 participants who underwent screening, 228 were randomized (mean [SD] age, 42.7 [14.5] years; 170 women [75%]), and 217 attended 6 or more of 8 sessions and provided posttest data. Participants in both programs improved from baseline to after treatment in primary outcomes of physical health QOL score (3RP-NF, 5.1; 95% CI, 3.2-7.0; P < .001; HEP-NF, 6.4; 95% CI, 4.6-8.3; P < .001) and psychological QOL score (3RP-NF, 8.5; 95% CI, 6.4-10.7; P < .001; HEP-NF, 9.2; 95% CI, 7.1-11.2; P < .001). Participants in the 3RP-NF group showed sustained improvements after treatment to 12 months; posttreatment improvements for the HEP-NF group diminished (between-group difference for physical health QOL score, 4.9; 95% CI, 2.1-7.7; P = .001; effect size [ES] = 0.3; and psychological QOL score, 3.7; 95% CI, 0.2-7.6; P = .06; ES = 0.2). Results were similar for secondary outcomes of social relationships and environmental QOL. There were significant between-group differences from baseline to 12 months in favor of the 3RP-NF for physical health QOL score (3.6; 95% CI, 0.5-6.6; P = .02; ES = 0.2), social relationships QOL score (6.9; 95% CI, 1.2-12.7; P = .02; ES = 0.3), and environmental QOL score (3.5; 95% CI, 0.4-6.5; P = .02; ES = 0.2). Conclusions and Relevance: In this randomized clinical trial of 3RP-NF vs HEP-NF, benefits from 3RP-NF and HEP-NF were comparable after treatment, but at 12 months from baseline, 3RP-NF was superior to HEP-NF on all primary and secondary outcomes. Results support the implementation of 3RP-NF in routine care. Trial Registration: ClinicalTrials.gov Identifier: NCT03406208.

Bavituximab Decreases Immunosuppressive Myeloid-Derived Suppressor Cells in Newly Diagnosed Glioblastoma Patients.

PURPOSE: We evaluated the efficacy of bavituximab-a mAb with anti-angiogenic and immunomodulatory properties-in newly diagnosed patients with glioblastoma (GBM) who also received radiotherapy and temozolomide. Perfusion MRI and myeloid-related gene transcription and inflammatory infiltrates in pre-and post-treatment tumor specimens were studied to evaluate on-target effects (NCT03139916). PATIENTS AND METHODS: Thirty-three adults with IDH--wild-type GBM received 6 weeks of concurrent chemoradiotherapy, followed by 6 cycles of temozolomide (C1-C6). Bavituximab was given weekly, starting week 1 of chemoradiotherapy, for at least 18 weeks. The primary endpoint was proportion of patients alive at 12 months (OS-12). The null hypothesis would be rejected if OS-12 was ≥72%. Relative cerebral blood flow (rCBF) and vascular permeability (Ktrans) were calculated from perfusion MRIs. Peripheral blood mononuclear cells and tumor tissue were analyzed pre-treatment and at disease progression using RNA transcriptomics and multispectral immunofluorescence for myeloid-derived suppressor cells (MDSC) and macrophages. RESULTS: The study met its primary endpoint with an OS-12 of 73% (95% confidence interval, 59%-90%). Decreased pre-C1 rCBF (HR, 4.63; P = 0.029) and increased pre-C1 Ktrans were associated with improved overall survival (HR, 0.09; P = 0.005). Pre-treatment overexpression of myeloid-related genes in tumor tissue was associated with longer survival. Post-treatment tumor specimens contained fewer immunosuppressive MDSCs (P = 0.01). CONCLUSIONS: Bavituximab has activity in newly diagnosed GBM and resulted in on-target depletion of intratumoral immunosuppressive MDSCs. Elevated pre-treatment expression of myeloid-related transcripts in GBM may predict response to bavituximab.

Prospective phase II trial of the dual mTORC1/2 inhibitor vistusertib for progressive or symptomatic meningiomas in persons with neurofibromatosis 2.

Background: Meningiomas occur in 80% of persons with neurofibromatosis 2 (NF2) and cause significant mortality and morbidity, yet there are no effective medical treatments. NF2-deficient tumors have constitutive activation of mammalian/mechanistic target of rapamycin (mTOR), and treatment with mTORC1 inhibitors results in growth arrest in a minority of tumors, with paradoxical activation of the mTORC2/AKT pathway. We studied the effect of vistusertib, a dual mTORC1/mTORC2 inhibitor, in NF2 patients with progressive or symptomatic meningiomas. Methods: Vistusertib was administered orally at 125 mg twice daily for 2 consecutive days each week. The primary endpoint was the imaging response in the target meningioma, defined as a volume decrease of 20% compared with the baseline. Secondary endpoints included toxicity, imaging response of nontarget tumors, quality of life, and genetic biomarkers. Results: Eighteen participants (13 female), median age of 41 (range, 18-61) years, were enrolled. In target meningiomas, the best response was partial response (PR) in 1/18 tumors (6%) and stable disease (SD) in 17/18 tumors (94%). For all measured intracranial meningiomas and vestibular schwannomas, the best imaging response was PR in 6/59 tumors (10%) and SD in 53 (90%). Treatment-related grade 3/4 adverse events occurred in 14 (78%) participants, and 9 participants discontinued treatment due to side effects. Conclusions: Although the study did not meet the primary endpoint, vistusertib treatment was associated with high rates of SD in progressive NF2-related tumors. However, this dosing regimen for vistusertib was poorly tolerated. Future studies of dual mTORC inhibitors for NF2 should focus on optimizing tolerability and evaluating the relevance of tumor stability in participants.

Vestibular dysfunction in neurofibromatosis type 2-related schwannomatosis.

Neurofibromatosis type 2-related schwannomatosis is a genetic disorder characterized by neurologic tumours, most typically vestibular schwannomas that originate on the vestibulo-cochlear nerve(s). Although vestibular symptoms can be disabling, vestibular function has never been carefully analysed in neurofibromatosis type 2-related schwannomatosis. Furthermore, chemotherapy (e.g. bevacizumab) can reduce tumour volume and improve hearing in neurofibromatosis type 2-related schwannomatosis, but nothing is known about its vestibular effects. In this report, we studied the three primary vestibular-mediated behaviours (eye movements, motion perception and balance), clinical vestibular disability (dizziness and ataxia), and imaging and hearing in eight untreated patients with neurofibromatosis type 2-related schwannomatosis and compared their results with normal subjects and patients with sporadic, unilateral vestibular schwannoma tumours. We also examined how bevacizumab affected two patients with neurofibromatosis type 2-related schwannomatosis. Vestibular schwannomas in neurofibromatosis type 2-related schwannomatosis degraded vestibular precision (inverse of variability, reflecting a reduced central signal-to-noise ratio) but not vestibular accuracy (amplitude relative to ideal amplitude, reflecting the central signal magnitude) and caused clinical disability. Bevacizumab improved vestibular precision and clinical disability in both patients with neurofibromatosis type 2-related schwannomatosis but did not affect vestibular accuracy. These results demonstrate that vestibular schwannoma tumours in our neurofibromatosis type 2-related schwannomatosis population degrade the central vestibular signal-to-noise ratio, while bevacizumab improves the signal-to-noise ratio, changes that can be explained mechanistically by the addition (schwannoma) and suppression (bevacizumab) of afferent neural noise.

Proteasomal pathway inhibition as a potential therapy for NF2-associated meningioma and schwannoma.

BACKGROUND: Neurofibromatosis 2 (NF2) is an inherited disorder caused by bi-allelic inactivation of the NF2 tumor suppressor gene. NF2-associated tumors, including schwannoma and meningioma, are resistant to chemotherapy, often recurring despite surgery and/or radiation, and have generally shown cytostatic response to signal transduction pathway inhibitors, highlighting the need for improved cytotoxic therapies. METHODS: Leveraging data from our previous high-throughput drug screening in NF2 preclinical models, we identified a class of compounds targeting the ubiquitin-proteasome pathway (UPP), and undertook studies using candidate UPP inhibitors, ixazomib/MLN9708, pevonedistat/MLN4924, and TAK-243/MLN7243. Employing human primary and immortalized meningioma (MN) cell lines, CRISPR-modified Schwann cells (SCs), and mouse Nf2-/- SCs, we performed dose response testing, flow cytometry-based Annexin V and cell cycle analyses, and RNA-sequencing to identify potential underlying mechanisms of apoptosis. In vivo efficacy was also assessed in orthotopic NF2-deficient meningioma and schwannoma tumor models. RESULTS: Testing of three UPP inhibitors demonstrated potent reduction in cell viability and induction of apoptosis for ixazomib or TAK-243, but not pevonedistat. In vitro analyses revealed that ixazomib or TAK-243 downregulates expression of c-KIT and PDGFRα, as well as the E3 ubiquitin ligase SKP2 while upregulating genes associated with endoplasmic reticulum stress-mediated activation of the unfolded protein response (UPR). In vivo treatment of mouse models revealed delayed tumor growth, suggesting a therapeutic potential. CONCLUSIONS: This study demonstrates the efficacy of proteasomal pathway inhibitors in meningioma and schwannoma preclinical models and lays the groundwork for use of these drugs as a promising novel treatment strategy for NF2 patients.

Imaging of Brain Tumors.

OBJECTIVE: This article focuses on neuroimaging as an essential tool for diagnosing brain tumors and monitoring response to treatment. LATEST DEVELOPMENTS: Neuroimaging is useful at all stages of brain tumor care. Technologic advances have improved the clinical diagnostic capability of neuroimaging as a vital complement to history, examination, and pathologic assessment. Presurgical evaluations are enriched by novel imaging techniques, through improved differential diagnosis and better surgical planning using functional MRI (fMRI) and diffusion tensor imaging. The common clinical challenge of differentiating tumor progression from treatment-related inflammatory change is aided by novel uses of perfusion imaging, susceptibility-weighted imaging (SWI), spectroscopy, and new positron emission tomography (PET) tracers. ESSENTIAL POINTS: Using the most up-to-date imaging techniques will facilitate high-quality clinical practice in the care of patients with brain tumors.

Genomic Patterns of Malignant Peripheral Nerve Sheath Tumor (MPNST) Evolution Correlate with Clinical Outcome and Are Detectable in Cell-Free DNA.

Malignant peripheral nerve sheath tumor (MPNST), an aggressive soft-tissue sarcoma, occurs in people with neurofibromatosis type 1 (NF1) and sporadically. Whole-genome and multiregional exome sequencing, transcriptomic, and methylation profiling of 95 tumor samples revealed the order of genomic events in tumor evolution. Following biallelic inactivation of NF1, loss of CDKN2A or TP53 with or without inactivation of polycomb repressive complex 2 (PRC2) leads to extensive somatic copy-number aberrations (SCNA). Distinct pathways of tumor evolution are associated with inactivation of PRC2 genes and H3K27 trimethylation (H3K27me3) status. Tumors with H3K27me3 loss evolve through extensive chromosomal losses followed by whole-genome doubling and chromosome 8 amplification, and show lower levels of immune cell infiltration. Retention of H3K27me3 leads to extensive genomic instability, but an immune cell-rich phenotype. Specific SCNAs detected in both tumor samples and cell-free DNA (cfDNA) act as a surrogate for H3K27me3 loss and immune infiltration, and predict prognosis. SIGNIFICANCE: MPNST is the most common cause of death and morbidity for individuals with NF1, a relatively common tumor predisposition syndrome. Our results suggest that somatic copy-number and methylation profiling of tumor or cfDNA could serve as a biomarker for early diagnosis and to stratify patients into prognostic and treatment-related subgroups. This article is highlighted in the In This Issue feature, p. 517.

COVID-19 in people with neurofibromatosis 1, neurofibromatosis 2, or schwannomatosis.

PURPOSE: People with pre-existing conditions may be more susceptible to severe COVID-19 when infected by SARS-CoV-2. The relative risk and severity of SARS-CoV-2 infection in people with rare diseases such as neurofibromatosis type 1 (NF1), neurofibromatosis type 2 (NF2), or schwannomatosis (SWN) is unknown. METHODS: We investigated the proportions of people with NF1, NF2, or SWN in the National COVID Cohort Collaborative (N3C) electronic health record data set who had a positive test result for SARS-CoV-2 or COVID-19. RESULTS: The cohort sizes in N3C were 2501 (NF1), 665 (NF2), and 762 (SWN). We compared these with N3C cohorts of patients with other rare diseases (98-9844 individuals) and the general non-NF population of 5.6 million. The site- and age-adjusted proportion of people with NF1, NF2, or SWN who had a positive test result for SARS-CoV-2 or COVID-19 (collectively termed positive cases) was not significantly higher than in individuals without NF or other selected rare diseases. There were no severe outcomes reported in the NF2 or SWN cohorts. The proportion of patients experiencing severe outcomes was no greater for people with NF1 than in cohorts with other rare diseases or the general population. CONCLUSION: Having NF1, NF2, or SWN does not appear to increase the risk of being SARS-CoV-2 positive or of being a patient with COVID-19 or of developing severe complications from SARS-CoV-2.

Ten-Year Follow-up of Internal Neurofibroma Growth Behavior in Adult Patients With Neurofibromatosis Type 1 Using Whole-Body MRI.

BACKGROUND AND OBJECTIVES: Internal neurofibromas, including plexiform neurofibromas (PNF), can cause significant morbidity in patients with neurofibromatosis type 1 (NF1). PNF growth is most pronounced in children and young adults, with more rapid growth thought to occur in a subset of PNF termed distinct nodular lesions (DNL). Growth behavior of internal neurofibromas and DNL in older adults is not well documented; yet knowledge thereof is important for patient risk stratification and clinical trial design. The primary objective of this study was to evaluate the long-term growth behavior of internal neurofibromas in adults with NF1. Secondary objectives were to correlate tumor growth behavior with patient-specific, tumor-specific, and patient-reported variables. METHODS: In this prospective cohort study, internal neurofibromas were identified on coronal short TI inversion recovery sequences on baseline and follow-up whole-body MRIs (WBMRIs). Tumor growth and shrinkage were defined as a volume change ≥20%. The association between tumor growth and patient-specific (baseline age, sex, and genotype), tumor-specific (morphology, location, DNL presence on baseline WBMRI, and maximum standardized uptake value on baseline PET imaging), and patient-reported variables (endogenous and exogenous hormone exposure, pain intensity, and quality of life) was assessed using the Spearman correlation coefficient and Kruskal-Wallis test. RESULTS: Of 106 patients with a baseline WBMRI obtained as part of a previous research study, 44 had a follow-up WBMRI. Three additional patients with WBMRIs acquired for clinical care were included, generating 47 adults for this study. The median age during baseline WBMRI was 42 years (range 18-70). The median time between WBMRIs was 10.4 years. Among 324 internal neurofibromas, 62.8% (56% of PNF and 62.1% of DNL) shrank spontaneously without treatment and 17.1% (17.9% of PNF and 13.8% of DNL) grew. Growth patterns were heterogeneous within participants. Patient-specific, tumor-specific, and patient-reported variables (including endogenous and exogenous hormone exposure) were not strong predictors of tumor growth. DISCUSSION: Internal neurofibroma growth behavior in older adults differs fundamentally from that in children and young adults, with most tumors, including DNL, demonstrating spontaneous shrinkage. Better growth models are needed to understand factors that influence tumor growth. These results will inform clinical trial design for internal neurofibromas.