Neuropathology最新文献

{"title":"MYB::QKI fusion-positive diffuse glioma of the cerebellum: A case report.","authors":"Kaishi Satomi, Takahiro Shibayama, Takashi Hibiya, Akimasa Hayashi, Kiyotaka Nagahama, Kenichiro Kato, Yukino Nikai, Yuko Matsushita, Miho Gomyo, Yuki Yamagishi, Nobuyoshi Sasaki, Kuniaki Saito, Keiichi Kobayashi, Anna Takeda, So Fujimoto, Takeshi Matsuo, Keisuke Takai, Takashi Komori, Kazuhiro Tsuchiya, Motoo Nagane, Koichi Ichimura, Junji Shibahara","doi":"10.1111/neup.13016","DOIUrl":"10.1111/neup.13016","url":null,"abstract":"<p><p>Angiocentric glioma (AG) is a supratentorial diffuse low-grade glioma characterized by the MYB::QKI fusion gene, showing angiocentric growth of monomorphous spindle cells with astrocytic and ependymal immunophenotypes. We describe a rare case of MYB::QKI fusion-positive diffuse cerebellar glioma in a 54-year-old male. The patient initially presented with a T2/FLAIR hyperintense lesion in the left cerebellar hemisphere and slowly progressive neurological symptoms. Histopathological evaluation revealed a diffuse glioma characterized by spindle-shaped and small epithelioid cells with perivascular infiltration. Immunohistochemistry showed positivity for glial fibrillary acidic protein and only occasionally positive for Olig2. No dot- or ring-like epithelial membrane antigen immunoreactivity was observed. In this case, the proliferative activity was higher than that in typical AG cases, as manifested by multiple mitoses (four mitoses/slide) and a Ki-67 labeling index of 5%. The tumor cells were negative for IDH1 p.R132H and H3 p.K28M mutation-specific antibodies. Fluorescence in situ hybridization showed a MYB break-apart signal, and reverse transcription-polymerase chain reaction analysis confirmed an in-frame MYB (6q23.3, exon 11, NM_001161659.2)::QKI (6q26, exon 5, NM_006775.3) fusion. IDH1 p.R132, IDH2 p.R172, H3-3A p.K28, H3C2 p.K28, and BRAF p.V600 were all wild type. DNA methylome profiling did not match any of the established methylation classes, including the four subtypes of diffuse glioma, MYB- or MYBL1-altered. Considering the results of DNA methylome profiling, the question remains as to whether this case represents a subset of AG (diffuse glioma, MYB/MYBL1-altered) or a distinct subtype. Although the morphological findings and the presence of fusion indicated that the tumor was a cerebellar AG, the DNA methylome profile did not match that of AG. An accumulation of more cases is needed to determine the precise nature of the tumor, which may lead to an expansion of the tumor concept.</p>","PeriodicalId":19204,"journal":{"name":"Neuropathology","volume":" ","pages":"228-233"},"PeriodicalIF":1.3,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142682248","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Morphometry of choroid plexus epithelial cells in neurodegenerative diseases.","authors":"Ryuta Murakami, Yoichi Chiba, Nobuyuki Miyatake, Yumi Miyai, Koichi Matsumoto, Keiji Wakamatsu, Yuko Saito, Manato Hara, Shigeo Murayama, Masaki Ueno","doi":"10.1111/neup.13019","DOIUrl":"10.1111/neup.13019","url":null,"abstract":"<p><p>The choroid plexus not only secretes the majority of cerebrospinal fluid but also controls the circadian rhythm, which can be impaired in the presence of neurodegenerative diseases. In addition, many studies have reported the contribution of choroid plexus abnormalities to the pathogenesis of neurodegenerative diseases, including Alzheimer's disease (AD). Formalin-fixed paraffin-embedded blocks were obtained from the lateral ventricles of the brains of four subjects with AD, four with vascular dementia, four with Parkinson's disease, three with multiple system atrophy, and five control patients with unremarkable neuropathological findings. They were sectioned and routinely stained with hematoxylin and eosin. Morphological analysis of epithelial cells in 10 high-power fields or a total area per case was conducted using digital images. There were no significant changes in any of the measurements: epithelial cell area, long and short axes, and ratio of the epithelial cell area to total stained area among the five groups. However, a simple linear regression analysis of epithelial cells in 20 patients showed that age was significantly correlated with the cell area, long axis, and short axis but not ratio. There were no effects of hypertension, diabetes mellitus, or calcification in the stroma on the measurements. These findings indicate that age was associated with the cell area and size in choroid plexus epithelial cells, whereas no significant changes in any epithelial cell measurements were present in neurodegenerative diseases.</p>","PeriodicalId":19204,"journal":{"name":"Neuropathology","volume":" ","pages":"202-209"},"PeriodicalIF":1.3,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12129643/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142739958","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Implications for soluble iron accumulation, oxidative stress, and glial glutamate release in motor neuron death associated with sporadic amyotrophic lateral sclerosis.","authors":"Noriyuki Shibata, Ikuko Kataoka, Yukinori Okamura, Kumiko Murakami, Yoichiro Kato, Tomoko Yamamoto, Kenta Masui","doi":"10.1111/neup.13033","DOIUrl":"10.1111/neup.13033","url":null,"abstract":"<p><p>Oxidative stress in sporadic amyotrophic lateral sclerosis (ALS) has been evidenced by accumulation of oxidatively modified products of nucleic acids, lipids, sugars, and proteins in the motor neuron system of brains and spinal cords obtained at autopsy from the patients. We recently demonstrated soluble iron accumulation in activated microglia of sporadic ALS spinal cords. This finding could indicate that iron-mediated Fenton reaction is most likely to be responsible for oxidative stress associated with this disease. The excitatory amino acid neurotoxicity hypothesis for sporadic ALS has been proposed based on increased glutamate and aspartate concentrations in cerebrospinal fluid from the patients. Initially, the increase in extracellular excitatory amino acid levels was considered to reflect excessive release from the axon terminal of upper motor neurons. However, it is a question of whether the damaged upper motor neurons continue releasing glutamate even in advanced stage of this disease. To address this issue, we hypothesized that glial cells might be a glutamate release source. Our immunohistochemical analysis on autopsied human spinal cords revealed that ferritin, hepcidin, ferroportin, aconitase 1, tumor necrosis factor-α (TNF-α), TNF-α-converting enzyme (TACE), and glutaminase-C (GAC) were expressed mainly in microglia and that cystine/glutamate antiporter (xCT) was expressed mainly in astrocytes. We next performed cell culture experiments. Cultured microglia treated with soluble iron over-released glutamate and TNF-α via aconitase 1 and TACE, respectively. Cultured microglia treated with TNF-α over-released glutamate via GAC. Cultured microglia treated with hepcidin, of which expression is known to be upregulated by TNF-α, showed downregulated expression of ferroportin. Cultured astrocytes treated with hydrogen peroxide over-released glutamate via xCT. These observations provide in vivo and in vitro evidence that microglia and astrocytes are glutamate suppliers in response to soluble iron overload and oxidative stress, respectively, in sporadic ALS.</p>","PeriodicalId":19204,"journal":{"name":"Neuropathology","volume":" ","pages":"177-201"},"PeriodicalIF":1.3,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12129649/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143597426","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A rare case of dedifferentiated intracranial solitary fibrous tumor with chondrosarcomatous differentiation.","authors":"Shikhar Chohan, Sana Ahuja, Sufian Zaheer","doi":"10.1111/neup.13023","DOIUrl":"10.1111/neup.13023","url":null,"abstract":"<p><p>This report details a rare case of a 30-year-old female presenting with neurological symptoms, including headaches, seizures, and left-sided weakness. Imaging revealed a mass in the right parafalcine region of her brain. Surgical resection identified a tumor with two distinct components. The first component exhibited characteristics of a classic solitary fibrous tumor (SFT) with typical fibroblastic cells and branching blood vessels. The second component showed high-grade sarcoma with chondrosarcomatous differentiation, a rare feature in SFT. Immunohistochemistry confirmed dedifferentiation with decreased STAT6 expression in the sarcomatous areas compared to the conventional SFT. This case highlights the challenges of managing dedifferentiated SFTs, especially in the brain, where surgical limitations increase risks. Despite the rarity of this presentation, it emphasizes the importance of recognizing this variant for appropriate diagnosis and management.</p>","PeriodicalId":19204,"journal":{"name":"Neuropathology","volume":" ","pages":"257-262"},"PeriodicalIF":1.3,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142838477","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Blood-brain barrier dysfunction in multiple system atrophy: A human postmortem study.","authors":"Ramil Gabdulkhaev, Hiroshi Shimizu, Masato Kanazawa, Yasuko Kuroha, Arika Hasegawa, Jiro Idezuka, Kazuki Tainaka, Osamu Onodera, Akiyoshi Kakita","doi":"10.1111/neup.13021","DOIUrl":"10.1111/neup.13021","url":null,"abstract":"<p><p>Multiple system atrophy (MSA) is a rare neurodegenerative disease characterized by an accumulation of phosphorylated α-synuclein (p-αsyn) in oligodendrocytes in the form of glial cytoplasmic inclusions (GCIs). In MSA, not only mature oligodendrocytes but also oligodendrocyte precursor cells (OPCs) are affected. The latter play an important role in remyelination by differentiating into mature oligodendrocytes, as well as maintaining the blood-brain barrier (BBB) by promoting the expression of tight junction proteins. We have hypothesized that in MSA, the BBB is impaired as a result of aberrant interactions between affected OPCs and the cerebral vasculature. To verify this hypothesis, we conducted a neuropathological examination of postmortem brains from MSA patients and control subjects, focusing on the primary motor area, one of the main regions affected in MSA. Using double immunofluorescence, we quantified the expression of tight junction protein claudin-5 in capillary endothelial cells and found that it was significantly lower in MSA than in controls in both the gray matter and white matter. Furthermore, a significantly higher amount of fibrinogen was extravasated into the brain parenchyma in MSA patients than in controls. In addition, leakage of IgG was detected almost specifically in MSA brain parenchyma, as visualized in three dimensions by combining techniques of chemical tissue clearing and light sheet microscopy. Finally, we confirmed accumulation of p-αsyn-positive GCIs along the cerebral vasculature within OPCs. These results suggest that BBB dysfunction and associated fibrinogen extravasation are constant findings in MSA, presumably triggered by the deposition of p-αsyn in perivascular OPCs.</p>","PeriodicalId":19204,"journal":{"name":"Neuropathology","volume":" ","pages":"210-222"},"PeriodicalIF":1.3,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142813781","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Amyloid-beta pathology in a case with dementia with Lewy bodies with a rapidly progressive clinical course similar to Creutzfeldt-Jacob disease.","authors":"Shintaro Fujii, Ikuko Takahashi-Iwata, Yuki Oshima, Kazuhiro Horiuchi, Zenichi Tanei, Katsuya Satoh, Tetsuyuki Kitamoto, Shinya Tanaka, Ichiro Yabe","doi":"10.1111/neup.13017","DOIUrl":"10.1111/neup.13017","url":null,"abstract":"<p><p>Most cases of dementia with Lewy bodies (DLB) follow a chronic course. However, some cases of rapidly progressive dementia (RPD) are difficult to distinguish from other diseases. Herein, we report how to differentiate DLB presenting with RPD from other diseases and its pathological features, with examples from our own experience. A 70-year-old man with RPD and psychiatric symptoms, including hallucinations and delusions, was transferred to our hospital. We suspected Creutzfeldt-Jakob disease (CJD), but disease-specific tests were all negative. The patient was treated with corticosteroids on the suspicion of an autoimmune condition; however, his symptoms did not improve. Based on the results of nuclear medicine and other tests, we suspected DLB and administered anti-Parkinsonian drugs; however, they were ineffective, and the patient died. Brain autopsy revealed extensive deposits of Lewy bodies, which were pathologically diagnosed as DLB. Additionally, extensive deposition of senile plaques was observed; however, neurofibrillary tangles (NFTs) were not prominent. DLB generally presents as a chronic disease. However, some patients with DLB present with RPD; therefore, the differential diagnosis of other diseases, such as CJD, is very important. In addition, although this case was not diagnosed with Alzheimer's disease (AD) due to the lack of NFTs, extensive amyloid deposition was observed in the brain tissue. Previous reports have described cases of RPD with amyloid deposition alone, and in this case too, it is suggested that amyloid deposition might have had a strong influence on the clinical course of RPD.</p>","PeriodicalId":19204,"journal":{"name":"Neuropathology","volume":" ","pages":"241-247"},"PeriodicalIF":1.3,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142770709","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Solitary fibrous tumor of the central nervous system with epithelioid neuroendocrine \"Transdedifferentiation\": A case report and review of the literatures.","authors":"Shazia Bokhari, Michael J Hwang, X Robert Zhang, Meenakshi B Bhattacharjee, Hidehiro Takei","doi":"10.1111/neup.13022","DOIUrl":"10.1111/neup.13022","url":null,"abstract":"<p><p>Solitary fibrous tumors (SFTs) of the central nervous system (CNS) are rare mesenchymal tumors characterized by a fusion of the NGFI-A-binding protein 2 (NAB2) gene and the signal transducer and activator of transcription 6 (STAT6) gene, immunohistochemically resulting in nuclear expression of STAT6 - an immunohistochemical hallmark essential for diagnosis, as outlined in the fifth edition of the World Health Organization Classification of Tumors. Dedifferentiation, where low-grade tumors transform into high-grade forms, has been observed in SFTs, with documented cases involving sarcomatous or rarely epithelial transformations. We report the first case of a CNS SFT exhibiting \"transdedifferentiation\" into epithelioid neuroendocrine differentiation. A 36-year-old woman presented with worsening frontal headaches and vision deterioration due to an 8.2-cm frontal tumor with skull erosion. Histologically, the tumor consisted of predominantly high-grade undifferentiated epithelioid round cells that expressed STAT6, along with multifocal synaptophysin and chromogranin A positivity, and occasional cytokeratin and claudin-4 reactivity, resembling large cell neuroendocrine carcinoma. A minor bland spindle cell component with STAT 6 immunoreactivity was also noted. This case highlights the rare occurrence of neuroendocrine \"transdedifferentiation\" in CNS SFTs. This case highlights the importance of recognizing dedifferentiation in CSF SFTs, which often correlates with aggressive tumor behavior and poor prognosis. Given the rarity of neuroendocrine \"transdedifferentiation,\" this case adds valuable insight into the diverse dedifferentiation patterns seen in CNS SFTs, emphasizing the need for accurate diagnosis to guide appropriate treatment strategies.</p>","PeriodicalId":19204,"journal":{"name":"Neuropathology","volume":" ","pages":"248-256"},"PeriodicalIF":1.3,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142838491","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A glioneuronal tumor with neurocytic rosettes harboring FGFR1 internal tandem duplication - A report of a unique case.","authors":"Jiri Soukup, Nikola Hajkova, Veronika Hajkova, Marian Svajdler, David Netuka, Martin Majovsky","doi":"10.1111/neup.13018","DOIUrl":"10.1111/neup.13018","url":null,"abstract":"<p><p>Rosette-forming glioneuronal tumors (RGNTs) with FGFR1 tyrosine kinase domain internal tandem duplication (FGFR1 ITD) is exceedingly rare, with only a few cases reported in the literature. Hereby we present a case of a tumor with RGNT morphology occurring in area of septum pellucidum of 43-year-old male. The tumor showed FGFR1 ITD, no PIK3CA, PIK3R1 or NF1 alterations and inconclusive methylation profile with match for class of \"low-grade glial/glioneuronal/neuroepithelial tumors\". No areas characteristic of dysembryoplastic neuroepithelial tumor were identified. A brief review of literature on discrepancies between morphological diagnosis of RGNT and molecular profile of the entity is provided.</p>","PeriodicalId":19204,"journal":{"name":"Neuropathology","volume":" ","pages":"234-240"},"PeriodicalIF":1.3,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142716666","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Utilizing quantitative susceptibility mapping to differentiate primary lateral sclerosis from progressive supranuclear palsy: A case report.","authors":"Hiroaki Sekiya, Ryota Satoh, Farwa Ali, Dennis W Dickson, Jennifer L Whitwell, Keith A Josephs","doi":"10.1111/neup.13015","DOIUrl":"10.1111/neup.13015","url":null,"abstract":"<p><p>We report a patient who presented clinically with progressive supranuclear palsy (PSP) but was pathologically diagnosed as having primary lateral sclerosis (PLS) with magnetic resonance imaging (MRI) with a quantitative susceptibility mapping (QSM) protocol. A 70-year-old man was clinically diagnosed with PSP due to early falls and unresponsiveness to levodopa therapy. Postmortem pathological examination revealed mild loss of Betz cells, gliosis, and transactive response DNA binding protein of 43 kDa (TDP-43)-positive inclusions in the motor cortex, leading to the pathological diagnosis of PLS. To explore methods for differentiating PLS from PSP, ante-mortem QSM images were visually and quantitatively assessed for abnormal increases in magnetic susceptibility in the motor cortex. Prussian blue and Luxol fast blue combined with periodic acid-Schiff staining were also performed to understand the source of the susceptibility increases. QSM showed clear hyperintense signals in the motor cortex. Magnetic susceptibility in the motor cortex was higher in the PLS patient (Z = 4.7, p < 0.001) compared to normal controls and pathologically diagnosed PSP patients. Pathological examination of the region showed intracortical myelin loss, as well as iron deposition. Underlying pathological processes for the increased magnetic susceptibility include not only iron deposition but also intracortical myelin. Our case suggests that QSM is a potential tool to differentiate PLS from PSP, providing insights for accurate diagnosis and enhancing clinical decision-making.</p>","PeriodicalId":19204,"journal":{"name":"Neuropathology","volume":" ","pages":"223-227"},"PeriodicalIF":1.3,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12085713/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142668626","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Solitary subependymal giant cell astrocytoma lacking TSC1/2 mutations and TTF-1 expression: A potential diagnostic pitfall.","authors":"Davide Mulone, Andrea Mafficini, Evelina Miele, Francesco Sala, Valeria Barresi","doi":"10.1111/neup.13013","DOIUrl":"10.1111/neup.13013","url":null,"abstract":"<p><p>Subependymal giant cell astrocytoma (SEGA) is a rare, low-grade glioma typically associated with tuberous sclerosis (TS) and mutations in the TSC1 or TSC2 genes. It is characterized by an intraventricular location, an expansive growth pattern, and the expression of glial and neural markers. TTF-1 expression is considered a sensitive marker of SEGA, likely reflecting its origin from progenitor cells in the caudothalamic groove. We report a case of SEGA with unusual immunohistochemical and molecular features in a 20-year-old man with no signs or family history of TS. The tumor was located in the anterior horn of the right ventricle and obstructed the foramen of Monro. Histologically, it exhibited an expansive growth pattern and was composed of cells with ovoid nuclei and abundant eosinophilic cytoplasm. Immunohistochemically, the tumor cells were positive for GFAP and S-100 protein, weakly positive for SOX2, focally positive for synaptophysin, and negative for TTF-1, neurofilament protein, NeuN, EMA, chromogranin, and BCOR. Scattered OLIG2-positive neoplastic cells were also observed. Molecular analysis revealed no pathogenic mutations or copy number variations in the analyzed 174 genes, including TSC1/2, except for a variant of unknown significance in BAP1. The histopathological features and immunohistochemical profile suggested SEGA, despite the absence of TTF-1 expression and TSC1/2 mutations. The diagnosis was confirmed by DNA methylation profiling, which assigned the tumor to the methylation class \"subependymal giant cell astrocytoma with TSC1/TSC2 alterations\" with a calibrated score of 0.95. This case highlights the potential diagnostic pitfall of SEGA lacking TTF-1 expression and emphasizes the importance of considering this entity in the differential diagnosis of intraventricular tumors, even in the absence of TS and characteristic molecular alterations. The existence of TTF-1 negative SEGAs reveals that these tumors might also derive from TTF-1 negative cells in the subpendymal region.</p>","PeriodicalId":19204,"journal":{"name":"Neuropathology","volume":" ","pages":"167-173"},"PeriodicalIF":1.3,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11962586/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142568316","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}