Neuropathology最新文献

The 2021 World Health Organization (WHO) classification of the central nervous system (CNS) tumors has classified diffuse leptomeningeal glioneuronal tumor (DLGNT) as a mixed neuronal and glial tumor. Here, we report a DLGNT with two distinct morphological tumor components but identical molecular features. A four-year-old female child presented with progressive right upper extremity weakness. Magnetic resonance imaging (MRI) revealed the leptomeningeal enhancement over the brain stem and cervicothoracic spine. The histological examination of surgical specimens revealed two distinct tumor components: approximately half of the tumor is composed of oligodendroglioma-like tumor intermingled with nodules of ganglioglioma-like tumor. Immunohistochemistry confirmed the oligodendroglioma and ganglioglioma features. The molecular genetic studies demonstrated the features of DLGNT, including fusion of KIAA1549::BRAF, deletion of chromosome 1p, and absence of isocitrate dehydrogenase 1/2 (IDH1/2) mutation in both tumor components. Interestingly, the genetic studies also revealed the distinct chromosomal abnormalities of the loss of chromosome 4 only in oligodendroglioma-like tumor and copy neutral loss of heterozygosity of 7Q34Q36.3 in the ganglioglioma-like tumor component. This case highlights the critical role of molecular testing in the diagnosis of rare cases of DLGNT with diverse morphological components as well as in the identification of unique molecular alternations responsible for morphological phenotypes of the distinct tumors in DLGNT.

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.

N-myc downstream regulated gene 1 (NDRG1) is a member of the NDRG family, of which four members (NDRG1, NDRG2, NDRG3, and NDRG4) have been identified. NDRG1 is repressed by c-MYC and N-MYC proto-oncogenes. NDRG1 is translated into a 43 kDa protein that is associated with the regulation of cellular stress responses, proliferation, and differentiation. In this study, we aimed to clarify the relationship between progression of glioblastoma (GB) IDH-wildtype and NDRG1 expression in tumor cells. We assessed the expression of NDRG1 in 41 GBs using immunostaining and evaluated its prognostic significance. NDRG1 expression by GBs was evaluated using Histoscore, which showed high and low scores in 23 and 18 cases, respectively. NDRG1-positive cells were strongly expressed in Ki-67 labeled proliferating tumor cells and CD105 positive proliferating microvessels around the area of palisading necrosis. Statistical analyses showed lower survival rates in the high-score group than the low-score group (P < 0.01). This study indicated that overexpression of NDRG1 by GB reflects tumor angiogenesis and poor patient prognosis.

A 55-year-old Japanese woman with a history of hypertension and right putaminal hemorrhage developed simultaneous hemorrhages in the left thalamus and putamen and died 24 h later. There were no vascular anomalies in the brain. Synaptophysin immunostaining combined with eosin azure 50 (EA50) staining clearly identified the hematoma and the surrounding brain structures. In the right cerebral hemisphere, a cystic lesion as a sequela of the usual type of hypertensive putaminal hematoma was evident. In the left cerebral hemisphere, two fresh hematomas were evident. One was a thalamic hematoma, which had destroyed the dorsal and medial structures of the thalamus, and the other was an unusual putaminal hematoma, which had destroyed the entire putamen and crossed the internal capsule and caudate nucleus. α-Smooth muscle actin immunostaining combined with EA50 and Victoria bleu staining demonstrated three ruptured arteries associated with fibrin aggregates in the anterior thalamic nucleus and anterior putamen. Some circular structures composed of fibrin, suggesting the presence of ruptured arteries in the neighborhood, were evident in the thalamus and putamen. In the putamen, ruptured arteries and circular structures were present in the lateral to medial areas. Fibrin aggregates in the anterior thalamic nucleus were more numerous than those in the putamen. On the basis of these findings, we concluded that: (i) the artery with numerous fibrin aggregates in the anterior thalamic nucleus had ruptured first, followed by the arteries distributed in other parts of the thalamus and putamen; (ii) the unusual putaminal hematoma was attributable to rupture of the arteries around the center of the putamen, which are not responsible for the usual type of hypertensive putaminal hematoma; and (iii) it is suggested that even if hypertensive hemorrhage occurs simultaneously in the ipsilateral putamen and thalamus, the usual type of hypertensive mixed-type hematoma does not form.

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.

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.

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.

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.

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.

Primary intracranial sarcomas constitute a rare group of tumors, with the most common types described in the literature being chondrosarcoma and fibrosarcoma. Dedifferentiated liposarcoma (DDLS) is a high-grade sarcoma that sometimes metastasizes to the brain. However, a primary intracranial DDLS is exceedingly rare. A 45-year-old patient from the Middle East came to India for treatment. His magnetic resonance imaging (MRI) scans revealed a space-occupying lesion at the level of the lateral ventricle T2/fluid attenuated inversion recovery hyperintensity with peripheral edema. A T1 perfusion map showed high relative cerebral blood volume values in the peripheral part, suggesting a high-grade neoplasm. Gross total resection was performed, and histopathology showed a high-grade tumor composed of sheets of pleomorphic lipoblasts and epithelioid tumor cells arranged in nests and cords. Immunohistochemistry showed diffuse immunopositivity for MDM2, CDK4, and p16, while GFAP and OLIG2 were negative. Fluorescence in situ hybridization showed MDM2 amplification. Final diagnosis of DDLS was rendered. The patient had no systemic lesions elsewhere on positron emission tomography computed tomography scan.