17 results on '"Yu Sakai"'
Search Results
2. Meningiomas in patients with neurofibromatosis type 2 predominantly comprise ‘immunogenic subtype’ tumours characterised by macrophage infiltration
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Yu Teranishi, Satoru Miyawaki, Masahiro Nakatochi, Atsushi Okano, Kenta Ohara, Hiroki Hongo, Daiichiro Ishigami, Yu Sakai, Daisuke Shimada, Shunsaku Takayanagi, Masako Ikemura, Daisuke Komura, Hiroto Katoh, Jun Mitsui, Shinichi Morishita, Tetsuo Ushiku, Shumpei Ishikawa, Hirofumi Nakatomi, and Nobuhito Saito
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Neurofibromatosis type 2 ,Meningioma ,Tumour microenvironment ,Immune infiltration ,Neurology. Diseases of the nervous system ,RC346-429 - Abstract
Abstract Although recent molecular analyses revealed that sporadic meningiomas have various genetic, epigenetic, and transcriptomic profiles, meningioma in patients with neurofibromatosis type 2 (NF2) have not been fully elucidated. This study investigated meningiomas' clinical, histological, and molecular characteristics in NF2 patients. A long-term retrospective follow-up (13.5 ± 5.5 years) study involving total 159 meningiomas in 37 patients with NF2 was performed. Their characteristics were assessed using immunohistochemistry (IHC), bulk-RNA sequencing, and copy number analysis. All variables of meningiomas in patients with NF2 were compared with those in 189 sporadic NF2-altered meningiomas in 189 patients. Most meningiomas in NF2 patients were stable, and the mean annual growth rate was 1.0 ± 1.8 cm3/year. Twenty-eight meningiomas (17.6%) in 25 patients (43.1%) were resected during the follow-up period. WHO grade I meningiomas in patients with NF2 were more frequent than in sporadic NF2-altered meningiomas (92.9% vs. 80.9%). Transcriptomic analysis for patients with NF2/sporadic NF2-altered WHO grade I meningiomas (n = 14 vs. 15, respectively) showed that tumours in NF2 patients still had a higher immune response and immune cell infiltration than sporadic NF2-altered meningiomas. Furthermore, RNA-seq/IHC-derived immunophenotyping corroborated this enhanced immune response by identifying myeloid cell infiltration, particularly in macrophages. Clinical, histological, and transcriptomic analyses of meningiomas in patients with NF2 demonstrated that meningiomas in NF2 patients showed less aggressive behaviour than sporadic NF2-altered meningiomas and elicited a marked immune response by identifying myeloid cell infiltration, particularly of macrophages.
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- 2023
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3. Imaging Biomarkers and Prevalence of Complex Aortic Plaque in Cryptogenic Stroke: A Systematic Review
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Yu Sakai, Quy Cao, Jeremy Rubin, Jens Witsch, Dan Cohen‐Addad, Katyucia de Macedo Rodrigues, Maria Begoña Coco‐Martin, Pouyan Pasyar, Jesús Juega, Zhaoyang Fan, Scott E. Kasner, Brett L. Cucchiara, and Jae W. Song
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aorta ,atherosclerosis ,biomarker ,imaging ,stroke ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Background Complex aortic plaque (CAP) is a potential embolic source in patients with cryptogenic stroke (CS). We review CAP imaging criteria for transesophageal echocardiogram (TEE), computed tomography angiography (CTA), and magnetic resonance imaging and calculate CAP prevalence in patients with acute CS. Methods and Results PubMed and EMBASE databases were searched up to December 2022 in accordance with the Preferred Reporting Items for Systematic Reviews and Meta‐Analyses guideline. Two independent reviewers extracted data on study design, imaging techniques, CAP criteria, and prevalence. The Cochrane Collaboration tool and Guideline for Reporting Reliability and Agreement Studies were used to assess risk of bias and reporting completeness, respectively. From 2293 studies, 45 were reviewed for CAP imaging biomarker criteria in patients with acute CS (N=37 TEE; N=9 CTA; N=6 magnetic resonance imaging). Most studies (74%) used ≥4 mm plaque thickness as the imaging criterion for CAP although ≥1 mm (N=1, CTA), ≥5 mm (N=5, TEE), and ≥6 mm (N=2, CTA) were also reported. Additional features included mobility, ulceration, thrombus, protrusions, and assessment of plaque composition. From 23 prospective studies, CAP was detected in 960 of 2778 patients with CS (0.32 [95% CI, 0.24–0.41], I2=94%). By modality, prevalence estimates were 0.29 (95% CI, 0.20–0.40; I2=95%) for TEE; 0.23 (95% CI, 0.15–0.34; I2=87%) for CTA and 0.22 (95% CI, 0.06–0.54; I2=92%) for magnetic resonance imaging. Conclusions TEE was commonly used to assess CAP in patients with CS. The most common CAP imaging biomarker was ≥4 mm plaque thickness. CAP was observed in one‐third of patients with acute CS. However, high study heterogeneity suggests a need for reproducible imaging methods.
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- 2023
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4. Validation of multiparametric MRI based prediction model in identification of pseudoprogression in glioblastomas
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Laiz Laura de Godoy, Suyash Mohan, Sumei Wang, MacLean P. Nasrallah, Yu Sakai, Donald M. O’Rourke, Stephen Bagley, Arati Desai, Laurie A. Loevner, Harish Poptani, and Sanjeev Chawla
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Glioblastoma ,Treatment response ,Multiparametric MRI ,Pseudoprogression ,Diffusion MR imaging ,Perfusion MR imaging ,Medicine - Abstract
Abstract Background Accurate differentiation of pseudoprogression (PsP) from tumor progression (TP) in glioblastomas (GBMs) is essential for appropriate clinical management and prognostication of these patients. In the present study, we sought to validate the findings of our previously developed multiparametric MRI model in a new cohort of GBM patients treated with standard therapy in identifying PsP cases. Methods Fifty-six GBM patients demonstrating enhancing lesions within 6 months after completion of concurrent chemo-radiotherapy (CCRT) underwent anatomical imaging, diffusion and perfusion MRI on a 3 T magnet. Subsequently, patients were classified as TP + mixed tumor (n = 37) and PsP (n = 19). When tumor specimens were available from repeat surgery, histopathologic findings were used to identify TP + mixed tumor (> 25% malignant features; n = 34) or PsP (
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- 2023
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5. Advances in Molecular Biological and Translational Studies in World Health Organization Grades 2 and 3 Meningiomas: A Literature Review
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Atsushi OKANO, Satoru MIYAWAKI, Yu TERANISHI, Kenta OHARA, Hiroki HONGO, Yu SAKAI, Daiichiro ISHIGAMI, Hirofumi NAKATOMI, and Nobuhito SAITO
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genomic alteration ,copy number alteration ,mrna expression ,dna methylation ,systemic medical therapy ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
The treatment of World Health Organization (WHO) grades 2 and 3 meningiomas remains difficult and controversial. The pathogenesis of high-grade meningiomas was expected to be elucidated to improve treatment strategies. The molecular biology of meningiomas has been clarified in recent years. High-grade meningiomas have been linked to NF2 mutations and 22q deletion. CDKN2A/B homozygous deletion and TERT promoter mutations are independent prognostic factors for WHO grade 3 meningiomas. In addition to 22q loss, 1p, 14p, and 9q loss have been linked to high-grade meningiomas. Meningiomas enriched in copy number alterations may be biologically invasive. Furthermore, several new comprehensive classifications of meningiomas have been proposed based on these molecular biological features, including DNA methylation status. The new classifications may have implications for treatment strategies for refractory aggressive meningiomas because they provide a more accurate prognosis compared to the conventional WHO classification. Although several systemic therapies, including molecular targeted therapies, may be effective in treating refractory aggressive meningiomas, these drugs are being tested. Systemic drug therapy for meningioma is expected to be developed in the future. Thus, this review aims to discuss the distinct genomic alterations observed in WHO grade 2 and 3 meningiomas, as well as their diagnostic and therapeutic implications and systemic drug therapies for high-grade meningiomas.
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- 2022
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6. Recurrent glioblastoma metastatic to the lumbar vertebra: A case report and literature review: Surgical oncology
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Ako Matsuhashi, Shota Tanaka, Hirokazu Takami, Masashi Nomura, Masako Ikemura, Yoshitaka Matsubayashi, Yusuke Shinoda, Keisuke Yamada, Yu Sakai, Yasuaki Karasawa, Shunsaku Takayanagi, and Nobuhito Saito
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glioblastoma ,vertebral metastasis ,craniotomy ,methylation array analysis ,copy number alteration ,chromosomal instability ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
BackgroundGlioblastoma is a malignant tumor, and its prognosis is as poor as 1.5 to 2 years. Most cases recur within one year even under the standard treatment. The majority of recurrences are local, and in rare cases, metastasize mostly within the centra nervous system. Extradural metastasis of glioma is exceedingly rare. Here, we present a case of vertebral metastasis of glioblastoma.Case presentationWe present a 21-year-old man post total resection of the right parietal glioblastoma, diagnosed with lumbar metastasis. He originally presented with impaired consciousness and left hemiplegia and underwent gross total resection of the tumor. Given the diagnosis of glioblastoma, he was treated with radiotherapy combined with concurrent and adjuvant temozolomide. Six months after tumor resection, the patient presented with severe back pain, and was diagnosed as metastatic glioblastoma on the first lumbar vertebrae. Posterior decompression with fixation and postoperative radiotherapy were conducted. He went on to receive temozolomide and bevacizumab. However, at 3 months after the diagnosis of lumbar metastasis, further disease progression was noted, and his care was transitioned to best supportive care. Comparison on copy number status between primary and metastatic lesions on methylation array analysis revealed more enhanced chromosomal instability including 7p loss, 7q gain and 8 gain in the metastatic lesion.ConclusionBased upon the literature review and our case, younger age of initial presentation, multiple surgical interventions, and long overall survival seem to be the risk factors of vertebral metastasis. As the prognosis of glioblastoma improves over time, its vertebral metastasis is seemingly more common. Therefore, extradural metastasis should be kept in mind in the treatment of glioblastoma. Further, detailed genomic analysis on multiple paired specimens is mandated to elucidate the molecular mechanisms of vertebral metastasis.
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- 2023
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7. Vessel wall MR imaging of aortic arch, cervical carotid and intracranial arteries in patients with embolic stroke of undetermined source: A narrative review
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Yu Sakai, Vance T. Lehman, Laura B. Eisenmenger, Emmanuel C. Obusez, G. Abbas Kharal, Jiayu Xiao, Grace J. Wang, Zhaoyang Fan, Brett L. Cucchiara, and Jae W. Song
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vessel wall MRI ,atherosclerosis ,imaging ,cerebrovascular disease/stroke ,embolic stroke of undetermined source (ESUS) ,stroke ,Neurology. Diseases of the nervous system ,RC346-429 - Abstract
Despite advancements in multi-modal imaging techniques, a substantial portion of ischemic stroke patients today remain without a diagnosed etiology after conventional workup. Based on existing diagnostic criteria, these ischemic stroke patients are subcategorized into having cryptogenic stroke (CS) or embolic stroke of undetermined source (ESUS). There is growing evidence that in these patients, non-cardiogenic embolic sources, in particular non-stenosing atherosclerotic plaque, may have significant contributory roles in their ischemic strokes. Recent advancements in vessel wall MRI (VW-MRI) have enabled imaging of vessel walls beyond the degree of luminal stenosis, and allows further characterization of atherosclerotic plaque components. Using this imaging technique, we are able to identify potential imaging biomarkers of vulnerable atherosclerotic plaques such as intraplaque hemorrhage, lipid rich necrotic core, and thin or ruptured fibrous caps. This review focuses on the existing evidence on the advantages of utilizing VW-MRI in ischemic stroke patients to identify culprit plaques in key anatomical areas, namely the cervical carotid arteries, intracranial arteries, and the aortic arch. For each anatomical area, the literature on potential imaging biomarkers of vulnerable plaques on VW-MRI as well as the VW-MRI literature in ESUS and CS patients are reviewed. Future directions on further elucidating ESUS and CS by the use of VW-MRI as well as exciting emerging techniques are reviewed.
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- 2022
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8. POLR2A Mutation is a Poor Prognostic Marker of Cerebellopontine Angle Meningioma.
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Atsushi Okano, Satoru Miyawaki, Yu Teranishi, Hiroki Hongo, Shogo Dofuku, Kenta Ohara, Yu Sakai, Masahiro Shin, Hirofumi Nakatomi, and Nobuhito Saito
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- 2024
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9. Clinical and Genetic Characteristics of Patients with Moyamoya Disease who Experienced Both Ischemic and Hemorrhagic Events
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Yudai Hirano, Satoru Miyawaki, Hideaki Imai, Hiroki Hongo, Yu Teranishi, Daiichiro Ishigami, Yu Sakai, Daisuke Shimada, Motoyuki Umekawa, Masafumi Segawa, Satoshi Koizumi, Hideaki Ono, Hirofumi Nakatomi, and Nobuhito Saito
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Surgery ,Neurology (clinical) - Published
- 2023
10. Complete Recanalization in Mechanical Thrombectomy Is Associated with Favorable Functional Outcome for M2 Occlusions
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Yu Sakai, Gakushi Yoshikawa, Satoshi Koizumi, Osamu Ishikawa, Akira Saito, and Katsuya Sato
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Neurology (clinical) ,Cardiology and Cardiovascular Medicine - Published
- 2023
11. Genetics of brain arteriovenous malformations and cerebral cavernous malformations
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Hiroki Hongo, Satoru Miyawaki, Yu Teranishi, Daiichiro Ishigami, Kenta Ohara, Yu Sakai, Daisuke Shimada, Motoyuki Umekawa, Satoshi Koizumi, Hideaki Ono, Hirofumi Nakatomi, and Nobuhito Saito
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Genetics ,Genetics (clinical) - Abstract
Cerebrovascular malformations comprise abnormal development of cerebral vasculature. They can result in hemorrhagic stroke due to rupture of lesions as well as seizures and neurological defects. The most common forms of cerebrovascular malformations are brain arteriovenous malformations (bAVMs) and cerebral cavernous malformations (CCMs). They occur in both sporadic and inherited forms. Rapidly evolving molecular genetic methodologies have helped to identify causative or associated genes involved in genesis of bAVMs and CCMs. In this review, we highlight the current knowledge regarding the genetic basis of these malformations.
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- 2022
12. CT Perfusion collateral index in assessment of collaterals in acute ischemic stroke with delayed presentation: Comparison to single phase CTA
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David S Liebeskind, Ahmed J. Awad, Jared Goldstein, J Mocco, Puneet Pawha, Jonathan Larson, Reade Deleacy, Hazem Shoirah, Amit Aggarwal, Max Wintermark, Gal Yaniv, Johanna T Fifi, Kambiz Nael, Jacob Deutsch, and Yu Sakai
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medicine.medical_specialty ,Imaging biomarker ,Computed Tomography Angiography ,Collateral ,Collateral Circulation ,Infarction ,Perfusion scanning ,Brain Ischemia ,Delayed presentation ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,cardiovascular diseases ,Stroke ,Ischemic Stroke ,Retrospective Studies ,Radiological and Ultrasound Technology ,business.industry ,medicine.disease ,Cerebral Angiography ,Perfusion ,Treatment Outcome ,Conventional PCI ,Neurology (clinical) ,Radiology ,Tomography, X-Ray Computed ,business - Abstract
Perfusion collateral index (PCI) has been recently defined as a promising measure of collateral status. We sought to compare collateral status assessed via CT-PCI in comparison to single-phase CTA and their relationship to outcome measures including final infarction volume, final recanalization status and functional outcome in ELVO patients.ELVO patients with anterior circulation large vessel occlusion who had baseline CTA and CT perfusion and underwent endovascular treatment were included. Collateral status was assessed on CTA. PCI from CT perfusion was calculated in each patient and an optimal threshold to separate good vs insufficient collaterals was identified using DSA as reference. The collateral status determined by CTA and PCI were assessed against 3 measured outcomes: 1) final infarction volume; 2) final recanalization status defined by TICI scores; 3) functional outcome measured by 90-day mRS.A total of 53 patients met inclusion criteria. Excellent recanalization defined by TICI ≥2C was achieved in 36 (68%) patients and 23 patients (43%) had good functional outcome (mRS ≤2). While having good collaterals on both CTA and CTP-PCI was associated with significantly (p0.05) smaller final infarction volume, only good collaterals status determined by CTP-PCI was associated with achieving excellent recanalization (p = 0.001) and good functional outcome (p = 0.003).CTP-based PCI outperforms CTA collateral scores in determination of excellent recanalization and good functional outcome and may be a promising imaging marker of collateral status in patients with delayed presentation of AIS.
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- 2022
13. A Case of Tailgut Cyst Treated with Laparoscopic Transabdominal and Transsacral Surgery
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Naoki Kawahara, Yoshiyuki Suzuki, Yu Sakai, Shinji Maeshima, and Takehiro Shimada
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Gastroenterology ,Surgery - Published
- 2022
14. Impact of the COVID-19 Pandemic on Anorectal Diseases
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Sayuri Matsushima, Nobuyoshi Miyajima, Yu Sakai, Ayumi Beniya, Yoshioki Hikosaka, Yoichi Kono, Remi Katori, Naomi Matsumura, Masahiko Fukano, Kosuke Okamoto, Yasuhiro Shimojima, and Makoto Matsushima
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Gastroenterology ,Surgery - Published
- 2022
15. Mechanical Thrombectomy for ICA Top Occlusion with Twig-Like MCA: A Case Report
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Gakushi Yoshikawa, Yu Sakai, and Katsuya Sato
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Mechanical thrombectomy ,medicine.medical_specialty ,business.industry ,Hemorrhagic complication ,Occlusion ,medicine ,Neurology (clinical) ,Cardiology and Cardiovascular Medicine ,business ,Surgery ,Twig - Published
- 2022
16. Abstract TP86: Systematic Review Of Aortic Atherosclerotic Plaque In Cryptogenic Stroke
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Yu Sakai, Quy Cao, Pouyan Pasyar, Peter B Noel, Jens Witsch, Scott E Kasner, Brett L Cucchiara, and Jae W Song
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Advanced and Specialized Nursing ,Neurology (clinical) ,Cardiology and Cardiovascular Medicine - Abstract
Introduction: In patients with cryptogenic stroke (CS), complex aortic plaque may be a potential underlying etiology. We performed a systematic review to determine the prevalence of complex aortic plaque in CS patients. Methods: A systematic review and meta-analysis were performed according to PRISMA guidelines (PROSPERO: CRD42022300865). PubMed and EMBASE databases were searched from Jan 1980 to Nov 2021 for studies assessing aortic (ascending, arch, descending) plaque by transesophageal echocardiogram (TEE), CT/CTA, or MRI in at least 10 CS patients. Prevalence rates were pooled using a random-effects model. I 2 statistics assessed heterogeneity. An Egger’s test assessed publication bias. Results: From 2712 articles, 31 met inclusion criteria. Ascending, arch, and descending aorta were assessed in 65%, 100%, 55% of studies, respectively. Studies investigated aortic plaque by TEE (84%), CT/CTA (19%) and MRI (16%). The prevalence of complex aortic plaque in 4666 CS patients was heterogeneous across studies and yielded a summary prevalence of 30% (95% CI 23-38%, I 2 = 96%; Figure 1) contrasting with 11% (95% CI 5-20%, I 2 =83%) in 677 patients without stroke. Prevalence rates in women and men were 26% (95% CI 14%-43%, I 2 = 94%) and 35% (95% CI 21-52%, I 2 = 97%), respectively. To investigate geographic differences, 14 studies from Europe were pooled (32%, 95% CI 23-43%, I 2 =93%), 3 from the Middle East (34%, 95% CI 11-67%, I 2 =94%) and 3 from the US (28%, 95% CI 13-51%, I 2 =90%). No publication bias was detected (p=0.66). Sources of heterogeneity included patient selection, imaging technology (e.g, transducer frequency) and plaque measurement criteria. Conclusions: Studies suggest a prevalence rate of complex aortic plaque in approximately 30% of CS patients. However, significant heterogeneity in the results indicate a need for less variability in CS patient selection and more reproducible imaging methods/criteria for detecting complex aortic plaque.
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- 2023
17. NF2 Alteration/22q Loss Is Associated with Recurrence in WHO Grade 1 Sphenoid Wing Meningiomas
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Yu Sakai, Satoru Miyawaki, Yu Teranishi, Atsushi Okano, Kenta Ohara, Hiroki Hongo, Daiichiro Ishigami, Daisuke Shimada, Jun Mitsui, Hirofumi Nakatomi, and Nobuhito Saito
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Cancer Research ,Oncology ,sphenoid wing meningioma ,recurrence ,NF2 - Abstract
Sphenoid wing meningiomas account for 11–20% of all intracranial meningiomas and have a higher recurrence rate than those at other sites. Recent molecular biological analyses of meningiomas have proposed new subgroups; however, the correlation between genetic background and recurrence in sphenoid wing meningiomas has not yet been fully elucidated. In this study, we evaluated the clinical characteristics, pathological diagnosis, and molecular background of 47 patients with sphenoid wing meningiomas. Variants of NF2, AKT1, KLF4, SMO, POLR2A, PIK3CA, TRAF7, and TERT were determined using Sanger sequencing, and 22q loss was detected using multiplex ligation-dependent probe amplification. Alterations were localized at NF2 in 11 cases, had other genotypes in 17 cases, and were not detected in 12 cases. Interestingly, WHO grade 1 meningiomas with NF2 alteration/22q loss (p = 0.008) and a MIB-1 labeling index > 4 (p = 0.03) were associated with a significantly shorter recurrence-free survival, and multivariate analysis revealed that NF2 alteration/22q loss was associated with recurrence (hazard ratio, 13.1). The duration of recurrence was significantly shorter for meningiomas with NF2 alteration/22q loss (p = 0.0007) even if gross-total resection was achieved. Together, these findings suggest that NF2 alteration/22q loss is associated with recurrence in WHO grade 1 sphenoid wing meningiomas.
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- 2022
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