Intraventricular central neurocytoma molecularly defined as extraventricular neurocytoma: a case representing the discrepancy between clinicopathological and molecular classifications
AbstractCentral neurocytoma (CN) is classically defined by its intraventricular location, neuronal/neurocytic differentiation, and histological resemblance to oligodendroglioma. Extraventricular neurocytoma (EVN) shares similar histological features with CN, while it distributes any site without contact with the ventricular system. CN and EVN have distinct methylation landscapes, and EVN has a signature fusion gene,FGFR1-TACC1. These characteristics distinguish between CN and EVN. A 30-year-old female underwent craniotomy and resection of a left intraventricular tumor at our institution. The histopathology demonstrated the...
Source: Brain Tumor Pathology - September 11, 2023 Category: Neurology Source Type: research
Diffuse paediatric-type high-grade glioma, H3-wildtype and IDH-wildtype: case series of a new entity
AbstractDiffuse paediatric-type high-grade glioma, H3-wildtype and IDH-wildtype (pHGG) is a rare and aggressive brain tumor characterized by a specific DNA methylation profile. It was recently introduced in the 5th World Health Organization classification of central nervous system tumors of 2021. Clinical data on this tumor is scarce. This is a case series, which presents the first clinical experience with this entity. We compiled a retrospective case series on pHGG patients treated between 2015 and 2022 at our institution. Data collected include patients ’ clinical course, surgical procedure, histopathology, genome-wide...
Source: Brain Tumor Pathology - August 10, 2023 Category: Neurology Source Type: research
Integrated analysis of multiple methods reveals characteristics of the immune microenvironment in medulloblastoma
AbstractTo explore the characteristics of the immune microenvironment (IME) of medulloblastoma (MB) by four methods: flow cytometry (FCM), immunohistochemical (IHC), bulk RNA expression and single cell RNA sequencing (scRNA-seq), we collected the intraoperative specimens of MB, ependymoma (EPN), high-grade glioma (HGG), and low-grade glioma (LGG) to make a cross-cancer comparison. The specimens were subjected to FCM and IHC respectively, and deconvolution from bulk RNA expression data and scRNA-seq analysis were performed in MB from the GEO database. FCM and IHC analysis found that the proportion of lymphocytes (LC) and T ...
Source: Brain Tumor Pathology - August 9, 2023 Category: Neurology Source Type: research
Spontaneous malignant transformation of trigeminal schwannoma: consideration of responsible gene alterations for tumorigenesis —a case report
AbstractMalignant peripheral nerve sheath tumors (MPNSTs) arising from the trigeminal nerves are extremely rare (only 45 cases, including the present case, have been published) and have been reported to develop de novo from the peripheral nerve sheath and are not transformed from a schwannoma or neurofibroma. Here, we report a case of MPNSTs of the trigeminal nerve caused by the malignant transformation of a trigeminal schwannoma, with a particular focus on genetic considerations. After undergoing a near-total resection of a histologically typical benign schwannoma, the patient presented with regrowth of the tumor 10 yea...
Source: Brain Tumor Pathology - July 29, 2023 Category: Neurology Source Type: research
A clinicopathological analysis of supratentorial ependymoma, ZFTA fusion-positive: utility of immunohistochemical detection of CDKN2A alterations and characteristics of the immune microenvironment
AbstractEPN-ZFTA is a rare brain tumor where prognostic factors remain unclear and no effective immunotherapy or chemotherapy is currently available. Therefore, this study investigated its clinicopathological features, evaluated the utility of MTAP and p16 IHC as surrogate markers ofCDKN2A alterations, and characterized the immune microenvironment of EPN-ZFTA. Thirty surgically removed brain tumors, including 10 EPN-ZFTA, were subjected to IHC. MLPA was performed forCDKN2A HD in 20 ependymal tumors, including EPN-ZFTA. The 5-years OS and PFS of EPN-ZFTA were 90% and 60%, respectively.CDKN2A HD was detected in two cases of ...
Source: Brain Tumor Pathology - June 16, 2023 Category: Neurology Source Type: research
α-SMA positive vascular mural cells suppress cyst formation in hemangioblastoma
This study investigated the involvement of mural cells in cyst formation. We analyzed the expression of α-smooth muscle actin (α-SMA), platelet-derived growth factor receptor-beta (PDGFRB), and CD31 in 39 consecutive human cerebellar HBs, 20 of cystic and 19 of solid type. Solid type HBs showed stronger diffuse expression of α-SMA in precapillary arterioles and capillaries within the tumor than cys tic type HBs (p = 0.001), whereas there was no difference in PDGFRB and CD31 expression. Detailed observation with immunofluorescence demonstrated that α-SMA was expressed in vascular mural cells surrounding capillaries ...
Source: Brain Tumor Pathology - June 5, 2023 Category: Neurology Source Type: research
IDH wild-type lower-grade gliomas with glioblastoma molecular features: a systematic review and meta-analysis
AbstractThe WHO 2021 classification defines IDH wild type (IDHw) histologically lower-grade glioma (hLGG) as molecular glioblastoma (mGBM) if TERT promoter mutation (pTERTm), EGFR amplification or chromosome seven gain and ten loss aberrations are indicated. We systematically reviewed articles of IDHw hLGGs studies (49 studies,N = 3748) and meta-analyzed mGBM prevalence and overall survival (OS) according to the PRISMA statement. mGBM rates in IDHw hLGG were significantly lower in Asian regions (43.7%, 95% confidence interval [CI: 35.8–52.0]) when compared to non-Asian regions (65.0%, [CI: 52.9–75.4]) (P = 0.00...
Source: Brain Tumor Pathology - May 22, 2023 Category: Neurology Source Type: research
Lynch syndrome-associated chordoma with high tumor mutational burden and significant response to immune checkpoint inhibitors
In this study, genetic analysis of the tumor in a 72-year-old male patient with refractory conventional chordoma of the skull base revealed a high tumor mutational burden (TMB) and mutations in theMSH6 andMLH1 genes, which are found in Lynch syndrome. The patient and his family had a dense cancer history, and subsequent germline genetic testing revealed Lynch syndrome. This is the first report of a chordoma that has been genetically proven to be Lynch syndrome. Chordomas usually have low TMB; however, this is an unusual case, because the TMB was high, and immune checkpoint inhibitors effectively controlled the tumor. This ...
Source: Brain Tumor Pathology - April 22, 2023 Category: Neurology Source Type: research
Immunohistochemical and ultrastructural review of six cases previously diagnosed as null cell PitNETs
AbstractPituitary neuroendocrine tumors (PitNETs) lacking lineage affiliation are termed “null cell” PitNETs (NCTs). NCTs are characterized as being immunonegative for pituitary hormones as well as transcription factors. We analyzed the ultrastructure and immunohistochemistry of six hormone-negative and transcription factor (TPIT, PIT1, SF1)-negative PitNETs, with less than 1% immun oreactive cells. Histologically, three cases presented a perivascular pattern and pseudorosettes; the other three showed a solid pattern with oncocytic changes. Electron microscopic examination revealed poorly differentiated tumor cells wit...
Source: Brain Tumor Pathology - April 18, 2023 Category: Neurology Source Type: research
Spatial metabolic heterogeneity of oligodendrogliomas at single-cell resolution
AbstractOligodendrogliomas are a type of rare and incurable gliomas whose metabolic profiles have yet to be fully examined. The present study examined the spatial differences in metabolic landscapes underlying oligodendrogliomas and should provide unique insights into the metabolic characteristics of these uncommon tumors. Single-cell RNA-sequencing expression profiles from 4044 oligodendroglioma cells derived from tumors resected from four locations frontal, temporal, parietal, and frontotemporoinsular) and in which 1p/19q co-deletion andIDH1 orIDH2 mutations were confirmed were computationally analyzed through a robust w...
Source: Brain Tumor Pathology - April 11, 2023 Category: Neurology Source Type: research
An enduring debate on gliomatosis cerebri
AbstractGliomatosis cerebri (GC) is a unique glial tumor that extensively invades the cerebral white matter and has been recognized as an entity of neuroepithelial tumors since the first edition of the WHO classification of brain tumors in 1979. Thereafter, in the fourth edition of the WHO classification in 2007, it was clearly defined as a specific type of astrocytic tumor. However, in the WHO 2016 classification, which was based on the concept of integrated diagnosis using molecular genetics, GC was deleted as it was considered to be only one growth pattern of diffuse glioma and not a specific pathological entity. Since ...
Source: Brain Tumor Pathology - April 6, 2023 Category: Neurology Source Type: research
Utility of genome-wide DNA methylation profiling for pediatric-type diffuse gliomas
AbstractDespite the current progress of treatment, pediatric-type diffuse glioma is one of the most lethal primary malignant tumors in the central nervous system (CNS). Since pediatric-type CNS tumors are rare disease entities and highly heterogeneous, the diagnosis is challenging. An accurate diagnosis is essential for the choice of optimal treatment, which leads to precision oncology and improvement of the patient ’s outcome. Genome-wide DNA methylation profiling recently emerged as one of the most important tools for the diagnosis of CNS tumors, and the utility of this novel assay has been reported in both pediatric a...
Source: Brain Tumor Pathology - April 1, 2023 Category: Neurology Source Type: research
Preface for Brain Tumor Pathology vol.40 issue 2
(Source: Brain Tumor Pathology)
Source: Brain Tumor Pathology - March 31, 2023 Category: Neurology Source Type: research
Impact of tumor markers on diagnosis, treatment and prognosis in CNS germ cell tumors: correlations with clinical practice and histopathology
AbstractTumor markers in CNS germ cell tumors (GCTs) include human chorionic gonadotropin (HCG) and alpha fetoprotein (AFP), which have significant diagnostic implications, as elevation of either one leads to clinical diagnosis of non-germinomatous GCTs without histopathological confirmation, justifying intensified chemotherapy and irradiation. The current study, based on an international cohort of histopathologically verified GCTs that underwent biopsy (n = 85) or resection (n = 76), sought to better define the clinical role and prognostic significance of tumor markers from serum and CSF in this challenging patient po...
Source: Brain Tumor Pathology - March 30, 2023 Category: Neurology Source Type: research
Easy-to-use machine learning system for the prediction of IDH mutation and 1p/19q codeletion using MRI images of adult-type diffuse gliomas
In this study, we established an easy-to-use computer-aided diagnosis system using Microsoft Azure Machine Learning Studio (MAMLS) to predict these statuses. We constructed an analysis model using 258 adult-type diffuse glioma cases from The Cancer Genome Atlas (TCGA) cohort. Using MRI T2-weighted images, the overall accuracy, sensitivity, and specificity for the prediction of IDH mutation and 1p/19q codeletion were 86.9%, 80.9%, and 92.0%, and 94.7%, 94.1%, and 95.1%, respectively. We also constructed an reliable analysis model for the prediction of IDH mutation and 1p/19q codeletion using an independent Nagoya cohort inc...
Source: Brain Tumor Pathology - March 29, 2023 Category: Neurology Source Type: research
