Ventricle-predominant primary CNS lymphomas: clinical, radiological and pathological evaluation of five cases and review of the literature
AbstractPrimary central nervous system lymphomas (PCNSLs) are typically intraparenchymal. A subset of PCNSLs predominantly arises in the ventricles, with minimal parenchymal involvement. We review the clinical, radiological, and pathological features of ventricle-predominant PCNSLs (VP-PCNSLs) in 40 previously reported cases and report 5 additional cases. Including all cases of VP-PCNSLs (n = 45), 38% were diffuse large B-cell lymphomas (DLBCL), 11% were Burkitt lymphomas, 7% were MALT lymphomas, 4% were T-cell lymphomas, and 40% were lymphomas, not otherwise classified. VP-PCNSLs show rapid clinical progress...
Source: Brain Tumor Pathology - October 19, 2019 Category: Neurology Source Type: research

Reviewers in 2019
(Source: Brain Tumor Pathology)
Source: Brain Tumor Pathology - September 12, 2019 Category: Neurology Source Type: research

Two cases of primary supratentorial intracranial rhabdomyosarcoma with DICER1 mutation which may belong to a “spindle cell sarcoma with rhabdomyosarcoma-like feature, DICER1 mutant”
AbstractRhabdomyosarcoma is the most common soft-tissue sarcoma affecting children and adolescents. It is defined as a malignant neoplasm characterized by morphologic, immunohistochemical, ultrastructural, or molecular genetic evidence of primary skeletal muscle differentiation, usually in the absence of any other pattern of differentiation. Primary intracranial rhabdomyosarcoma (PIRMS) is an extremely rare neoplasm, with only 60 cases reported in the literature, and generally has poor prognosis with an overall survival of only 9.1  months. TheDICER1 gene encodes an RNA endoribonuclease that plays a key role in gene e...
Source: Brain Tumor Pathology - September 5, 2019 Category: Neurology Source Type: research

First autopsy analysis of the efficacy of intra-operative additional photodynamic therapy for patients with glioblastoma
AbstractThe study aim to demonstrate the therapeutic tissue depth of photodynamic therapy (PDT) using the photosensitizer talaporfin sodium and semiconductor laser for malignant glioma from an autopsy finding. Three patients diagnosed with glioblastoma by pre-operative imaging (1 newly diagnosed patient and 2 patients with recurrence) were treated with intra-operative additional PDT and adjuvant therapy such as post-operative radiotherapy or chemotherapy. All three patients died of brain stem dysfunction owing to cerebrospinal fluid dissemination or direct invasion of the tumor cells from 13, 18, or 20  months after P...
Source: Brain Tumor Pathology - September 5, 2019 Category: Neurology Source Type: research

Clinicopathological evaluation of PD-L1 expression and cytotoxic T-lymphocyte infiltrates across intracranial molecular subgroups of ependymomas: are these tumors potential candidates for immune check-point blockade?
AbstractImmune check-point blockade (ICB) targeting programmed cell death ligand-1 (PD-L1)/programmed death-1 (PD-1) axis has created paradigm shift in cancer treatment. ‘ST-RELA’ and ‘PF-A’ molecular subgroups of ependymomas (EPN) show poor outcomes. We aimed to understand the potential candidature of EPNs for ICB. Supratentorial (ST) Grade II/III EPNs were classified into ST-RELA, ST-YAP, and ST-not otherwise specified (NOS), based onRELA/YAP1 fusion transcripts and/or L1CAM and p65 protein expression. Posterior fossa (PF) EPNs were classified into PF-A and PF-B based on H3K27me3 expression. Immun...
Source: Brain Tumor Pathology - August 6, 2019 Category: Neurology Source Type: research

Anaplastic pleomorphic xanthoastrocytoma associated with an H3G34 mutation: a case report with review of literature
AbstractHere, we report a rare case of anaplastic pleomorphic xanthoastrocytoma (PXA) associated with an H3G34 mutation. A 12-year-old male presented with loss of appetite, vomiting, headache, and a generalized seizure, and CT revealed a 9.0  cm left frontal lobe mass with some septal walls and a localized high-density area suggestive of hemorrhage or calcification, causing severe midline shift. He emergently underwent subtotal resection and the tumor was morphologically diagnosed as anaplastic PXA. DNA sequencing identified an H3F3A G 34R mutation and a TP53 R273H mutation, and immunohistochemically, ATRX nuclear exp...
Source: Brain Tumor Pathology - July 26, 2019 Category: Neurology Source Type: research

Clinical, histopathological, and molecular analyses of IDH -wild-type WHO grade II –III gliomas to establish genetic predictors of poor prognosis
This study analyzed the genetic and other features ofIDH-wt LGGs to develop a subclassification that can be used to predict their prognosis. Clinical, histopathological, and genetic features of 35 cases of diffuseIDH-wt astrocytoma andIDH-wt anaplastic astrocytoma were analyzed. The following genetic factors were examined: mutations ofB-rapidly accelerated fibrosarcoma,telomerase reverse transcriptase promoter (TERTp),histone 3 family 3A, andalpha-thalassemia/mental retardation syndrome,X-linked; and copy number aberrations. In the univariate analysis, the following factors were associated with poor overall survival (OS): ...
Source: Brain Tumor Pathology - July 19, 2019 Category: Neurology Source Type: research

A long-term survivor of pediatric midline glioma with H3F3A K27M and BRAF V600E double mutations
We report a case of 2-year-old female with lateral ventricular glioma harboring bothH3F3A K27M andBRAF V600E mutations. By the methylation analysis, the tumor was classified as a diffuse midline glioma H3 K27M mutant, WHO grade IV. However, the tumor was pathologically low-grade and likely localized rather than diffusely infiltrating. Further, the patient has survived more than 8  years after gross total resection of the tumor. Whereas bothH3F3A K27M andBRAF V600E have been reported as poor prognostic markers in pediatric glioma, our case, along with several other reported cases, suggests that the coexistence of these...
Source: Brain Tumor Pathology - June 28, 2019 Category: Neurology Source Type: research

MN1 rearrangement in astroblastoma: study of eight cases and review of literature
AbstractAstroblastomas are unique tumours with unresolved issues in terms of their origin, molecular biology, clinical behaviour, and response to treatment. To decipher the characteristics of this tumour, we reviewed cases histologically diagnosed as astroblastoma in our institute over the past 8  years, with immunohistochemistry, and performed fluorescence in situ hybridisation (FISH), for the newly emergedMN1 rearrangement which was reported in central nervous system high-grade neuroepithelial tumours. The mean age at diagnosis was 18.6  years with all cases seen in females and with supratentorial localisation....
Source: Brain Tumor Pathology - May 20, 2019 Category: Neurology Source Type: research

High-grade glioneuronal tumor with an ARHGEF2 – NTRK1 fusion gene
AbstractHere, we report a highly unusual case of high-grade glioneuronal tumor with aneurotrophic tropomyosin receptor kinase (NTRK) fusion gene. A 13-year-old girl presented with headache and vomiting and MRI detected two cystic lesions bilaterally in the frontal areas with surrounding edema. The left larger tumor was removed by left frontal craniotomy. The tumor was diagnosed as a high-grade glioneuronal tumor, unclassified. Methylation profiling classified it as a diffuse leptomeningeal glioneuronal tumor (DLGNT) with low confidence. This tumor showed genotypes frequently found in DLGNT such as 1p/19q codeletion without...
Source: Brain Tumor Pathology - April 22, 2019 Category: Neurology Source Type: research

Clinicopathological characteristics of circumscribed high-grade astrocytomas with an unusual combination of BRAF V600E, ATRX , and CDKN2A/B alternations
We report four cases of high-grade astrocytoma with aBRAF V600E mutation,ATRX inactivation, andCDKN2A/B homozygous deletion. Children to young adults aged 3 –46 presented with a well demarcated contrast-enhancing mass in the supratentorial area. Pathological examination revealed packed growth of short spindle to round polygonal cells including some pleomorphic cells. The tumors had less ability to infiltrate into the adjacent brain parenchyma and pres ented a circumscribed growth pattern. Mitosis was readily found, accompanied by focal necrosis and/or microvascular proliferation. Tumors were histologically similar in...
Source: Brain Tumor Pathology - April 10, 2019 Category: Neurology Source Type: research

Novel concept of the border niche: glioblastoma cells use oligodendrocytes progenitor cells (GAOs) and microglia to acquire stem cell-like features
AbstractGlioblastoma (GBM) is a major malignant brain tumor developing in adult brain white matter, characterized by rapid growth and invasion. GBM cells spread into the contralateral hemisphere, even during early tumor development. However, after complete resection of tumor mass, GBM commonly recurs around the tumor removal cavity, suggesting that a microenvironment at the tumor border provides chemo-radioresistance to GBM cells. Thus, clarification of the tumor border microenvironment is critical for improving prognosis in GBM patients. MicroRNA (miRNA) expression in samples from the tumor, tumor border, and peripheral r...
Source: Brain Tumor Pathology - April 9, 2019 Category: Neurology Source Type: research

Preface
(Source: Brain Tumor Pathology)
Source: Brain Tumor Pathology - April 8, 2019 Category: Neurology Source Type: research

Pilomyxoid astrocytomas: a short review
AbstractPilomyxoid astrocytoma is a variant of pilocytic astrocytoma and the clinical, histological and molecular data point to a very close relationship as well as a more aggressive biological behavior for the former. WHO 2016 classification does not provide a specific grade for these neoplasms, but there is sufficient evidence in the literature that pilomyxoid astrocytoma has slightly worse prognosis than typical pilocytic astrocytoma. There is increasing evidence that in addition to the MAPK pathway alterations, pilomyxoid astrocytomas harbor genetic alterations that distinguish them from typical pilocytic astrocytoma (...
Source: Brain Tumor Pathology - April 3, 2019 Category: Neurology Source Type: research

Overview of DNA methylation in adult diffuse gliomas
AbstractAdult diffuse gliomas form a heterogeneous group of tumors of the central nervous system that vary greatly in histology and prognosis. A significant advance during the last decade has been the identification of a set of genetic lesions that correlate well with histology and clinical outcome in diffuse gliomas. Most characteristic driver mutations consist ofisocitrate dehydrogenase 1 (IDH1) andIDH2, andH3 histone family member 3A, which are strongly associated with DNA and histone methylation patterns. A well-characterized DNA methylation aberration is on the O6-methylguanine-DNA methyltransferase promoter. This abe...
Source: Brain Tumor Pathology - April 1, 2019 Category: Neurology Source Type: research

Molecular genetics and therapeutic targets of pediatric low-grade gliomas
AbstractPediatric low-grade gliomas (PLGGs) have relatively favorable prognosis and some resectable PLGGs, such as cerebellar pilocytic astrocytoma, can be cured by surgery alone. However, many PLGG cases are unresectable and some of them undergo tumor progression. Therefore, a multidisciplinary approach is necessary to treat PLGG patients. Recent genomic analysis revealed a broad genomic landscape underlying PLGG. Notably, the majority of PLGGs present MAPK pathway-associated genomic alterations and MAPK signaling-dependent tumor progression. Following preclinical evidence, many clinical trials based on molecular target t...
Source: Brain Tumor Pathology - March 30, 2019 Category: Neurology Source Type: research

Review of ependymomas: assessment of consensus in pathological diagnosis and correlations with genetic profiles and outcome
This study indicated that the expert consensus pathological diagnosis could correlate well with the molecular classifications in EPNs. ST EPNs should be diagnosed more carefully by histological and molecular analyses. (Source: Brain Tumor Pathology)
Source: Brain Tumor Pathology - March 30, 2019 Category: Neurology Source Type: research

The emerging clinical potential of circulating extracellular vesicles for non-invasive glioma diagnosis and disease monitoring
AbstractDiffuse gliomas (grades II –IV) are amongst the most frequent and devastating primary brain tumours of adults. Currently, patients are monitored by clinical examination and radiographic imaging, which can be challenging to interpret and insensitive to early signs of treatment failure and tumour relapse. While brain biopsy a nd histologic analysis can evaluate disease progression, serial biopsies are invasive and impractical given the cumulative surgical risk, and may not capture the complete molecular landscape of an evolving tumour. The availability of a minimally invasive ‘liquid biopsy’ that co...
Source: Brain Tumor Pathology - March 11, 2019 Category: Neurology Source Type: research

Pathologic and molecular aspects of anaplasia in circumscribed gliomas and glioneuronal tumors
AbstractMany breakthroughs have been made in the past decade regarding our knowledge of the biological basis of the diffuse gliomas, the most common primary central nervous system (CNS) tumors. These tumors as a group are aggressive, associated with high mortality, and have a predilection for adults. However, a subset of CNS glial and glioneuronal tumors are characterized by a more circumscribed pattern of growth and occur more commonly in children and young adults. They tend to be indolent, but our understanding of anaplastic changes in these tumors continues to improve as diagnostic classifications evolve in the era of m...
Source: Brain Tumor Pathology - March 11, 2019 Category: Neurology Source Type: research

Practical procedures for the integrated diagnosis of astrocytic and oligodendroglial tumors
AbstractThe publication of the 2016 World Health Organization Classification of Tumors of the Central Nervous System (2016 WHO CNS) represented a major change in the classification of brain tumors. However, many pathologists in Japan cannot diagnose astrocytic or oligodendroglial tumors according to the 2016 WHO CNS due to financial or technical problems. Therefore, the Japan Society of Brain Tumor Pathology established a committee for molecular diagnosis to facilitate the integrated diagnosis of astrocytic and oligodendroglial tumors in Japan. We created three levels of diagnoses: Level 1 was defined as simple histopathol...
Source: Brain Tumor Pathology - March 7, 2019 Category: Neurology Source Type: research

Next-generation whole exome sequencing of glioblastoma with a primitive neuronal component
AbstractGlioblastoma with a primitive neuronal component (GBM-PN) was renamed from glioblastoma with primitive neuroectodermal tumor-like component (GBM-PNET) in the new WHO classification of tumors of the central nervous system in 2016. GBM-PN is a rare variant of glioblastoma. There were not so many publications on the investigation of GBM-PN. We did whole exome sequencing for 11 GBM-PN cases and found that the percentage of TP53, PIK3CA, PIK3R1, or PTEN mutation in our GBM-PN cases (72.7%, 27.3%, 27.3%, and 27.3%  respectively) was much higher than that in cases in TCGA GBM 2008, TCGA GBM 2013, and TCGA lower-grade...
Source: Brain Tumor Pathology - February 4, 2019 Category: Neurology Source Type: research

A rapidly fatal intracranial anaplastic hemangiopericytoma with de-novo dedifferentiation: emphasis on diagnostic recognition, molecular confirmation and discussion on treatment dilemma
We report a unique case of an intracranial anaplastic SFT/HPC with de-novo dedifferentiation, which pursued a rapidly fatal clinical course in a 41-year-old lady. The dedifferentiated component comprised a focal area of glandular formation with epithelial immunophenotype acquisition. The distinct biphasic pattern of the tumor imparted great diagnostic challenges to the pathologists. An increased awareness of SFT/HPCs with a diverse morphologic spectrum or even a biphasic histologic pattern is essential in working up such cases. We first attempted gamma knife radiosurgery in treating a recurrent dedifferentiated SFT/HPC; un...
Source: Brain Tumor Pathology - January 2, 2019 Category: Neurology Source Type: research

Immunohistochemical detection of ALK protein identifies APC mutated medulloblastoma and differentiates the WNT-activated medulloblastoma from other types of posterior fossa childhood tumors
AbstractExpression of theALK gene strongly correlates with the WNT-activated medulloblastomas, which are routinely identified by detection ofCTNNB1 mutation. However, some tumors have mutations in other thanCTNNB1 genes. Therefore, we investigated if ALK expression may identify WNT-activated tumors withoutCTNNB1 mutation. In addition, we examined if ALK expression may differentiate WNT-activated medulloblastoma from other malignant posterior fossa tumors. ALK expression was analyzed using immunohistochemistry (clone D5F3) in 70 patients with posterior fossa tumours. Among 55 medulloblastomas, 6 tumors showed ALK expression...
Source: Brain Tumor Pathology - December 6, 2018 Category: Neurology Source Type: research

The clinicopathological analysis of receptor tyrosine kinases in meningiomas: the expression of VEGFR-2 in meningioma was associated with a higher WHO grade and shorter progression-free survival
In conclusion, our study suggests that VEGFR-2 inhibitors might be one of the best candidates for molecular therapy against recurre nt meningiomas. (Source: Brain Tumor Pathology)
Source: Brain Tumor Pathology - December 5, 2018 Category: Neurology Source Type: research

Identification of a novel KLC1 –ROS1 fusion in a case of pediatric low-grade localized glioma
We describe a novelKLC1 –ROS1 fusion identified in a case of pediatric low-grade glioma. This was detected by RNA sequencing and confirmed by reverse-transcription PCR and fluorescent in situ hybridization. Immunohistochemical staining for ROS1 was positive in the tumor cytoplasm. In vitro analysis demonstrated the oncogenic activity of this fusion, which was suppressed by the ALK/ROS1 inhibitor, crizotinib. Our case and others suggest that various ROS1 fusions might be present in a subset of pediatric gliomas, which could be targeted for therapy. (Source: Brain Tumor Pathology)
Source: Brain Tumor Pathology - October 22, 2018 Category: Neurology Source Type: research

Molecular profiling of different glioma specimens from an Ollier disease patient suggests a multifocal disease process in the setting of IDH mosaicism
AbstractOllier disease (OD) and Maffucci syndrome are rare conditions due to a post-zygotic somatic mutation that results in mosaicism. In addition to enchondromas and hemangiomas, some of these patients also develop other unrelated tumors, such as gliomas, that harborIDH mutations, suggesting that anIDH mutation is a common genetic event in the tumorigenesis in this group of patients. We illustrate an interesting case of multifocalIDH-mutant astrocytomas in an OD patient with 8  years of follow-up. We first demonstrated identicalIDH mutations in the brain tumor samples from various locations in this patient, but diff...
Source: Brain Tumor Pathology - October 1, 2018 Category: Neurology Source Type: research

Anaplastic changes of diffuse leptomeningeal glioneuronal tumor with polar spongioblastoma pattern
AbstractDiffuse leptomeningeal glioneuronal tumor (DLGNT) is a rare glioneuronal neoplasm with oligodendroglioma-like cells confined in the subarachnoid spaces. A great majority of DLGNT are histologically low grade. However, some tumors show features of anaplasia with increased mitotic and proliferative activity. Due to the limited number of patients and inadequate clinical follow-up reported to date, the WHO classification does not yet assign a distinct WHO grade to this entity. Polar spongioblastoma pattern, in which bipolar cells are arranged in parallel with palisading nuclei, remains poorly understood about the patho...
Source: Brain Tumor Pathology - October 1, 2018 Category: Neurology Source Type: research

NRAS Q61K mutated diffuse leptomeningeal melanomatosis in an adult patient with a brief review of the so-called “forme fruste” of neurocutaneous melanosis
AbstractPrimary melanocytic tumors of central nervous system represent rare tumors arising from melanocytes of the leptomeninges. These neoplasms include focal forms like melanocytoma and primary malignant melanoma and diffuse forms like leptomeningeal melanocytosis and primary leptomeningeal melanomatosis. The clinical diagnosis remains challenging, with clinical and radiologic features overlapping with other more common diseases. Here we present a case of a 38  years old male with primary diffuse leptomeningeal melanomatosis with presence of aNRASQ61K mutation without features of neurocutaneous melanosis. (Source: B...
Source: Brain Tumor Pathology - October 1, 2018 Category: Neurology Source Type: research

Stromal cells of hemangioblastomas exhibit mesenchymal stem cell-derived vascular progenitor cell properties
In conclusion, s tromal cells of hemangioblastomas exhibit mesenchymal stem cell-derived vascular progenitor cell properties. (Source: Brain Tumor Pathology)
Source: Brain Tumor Pathology - October 1, 2018 Category: Neurology Source Type: research

Reviewers in 2018
(Source: Brain Tumor Pathology)
Source: Brain Tumor Pathology - September 5, 2018 Category: Neurology Source Type: research

Molecular profiling of different glioma specimens from an Ollier disease patient suggests a multifocal disease process in the setting of IDH mosaicism
AbstractOllier disease (OD) and Maffucci syndrome are rare conditions due to a post-zygotic somatic mutation that results in mosaicism. In addition to enchondromas and hemangiomas, some of these patients also develop other unrelated tumors, such as gliomas, that harborIDH mutations, suggesting that anIDH mutation is a common genetic event in the tumorigenesis in this group of patients. We illustrate an interesting case of multifocalIDH-mutant astrocytomas in an OD patient with 8  years of follow-up. We first demonstrated identicalIDH mutations in the brain tumor samples from various locations in this patient, but diff...
Source: Brain Tumor Pathology - August 29, 2018 Category: Neurology Source Type: research

NRAS Q61K mutated diffuse leptomeningeal melanomatosis in an adult patient with a brief review of the so-called “forme fruste” of neurocutaneous melanosis
AbstractPrimary melanocytic tumors of central nervous system represent rare tumors arising from melanocytes of the leptomeninges. These neoplasms include focal forms like melanocytoma and primary malignant melanoma and diffuse forms like leptomeningeal melanocytosis and primary leptomeningeal melanomatosis. The clinical diagnosis remains challenging, with clinical and radiologic features overlapping with other more common diseases. Here we present a case of a 38  years old male with primary diffuse leptomeningeal melanomatosis with presence of aNRASQ61K mutation without features of neurocutaneous melanosis. (Source: B...
Source: Brain Tumor Pathology - August 25, 2018 Category: Neurology Source Type: research

Anaplastic changes of diffuse leptomeningeal glioneuronal tumor with polar spongioblastoma pattern
AbstractDiffuse leptomeningeal glioneuronal tumor (DLGNT) is a rare glioneuronal neoplasm with oligodendroglioma-like cells confined in the subarachnoid spaces. A great majority of DLGNT are histologically low grade. However, some tumors show features of anaplasia with increased mitotic and proliferative activity. Due to the limited number of patients and inadequate clinical follow-up reported to date, the WHO classification does not yet assign a distinct WHO grade to this entity. Polar spongioblastoma pattern, in which bipolar cells are arranged in parallel with palisading nuclei, remains poorly understood about the patho...
Source: Brain Tumor Pathology - July 26, 2018 Category: Neurology Source Type: research

Paediatric diffuse leptomeningeal tumor with glial and neuronal differentiation harbouring chromosome 1p/19q co-deletion and H3.3 K27M mutation: unusual molecular profile and its therapeutic implications
We present a rare instance of a DL-GNT in a 13-year-old female who presented with slowly progressive and sequential neurological deficits over a 12-month duration. Imaging showed leptomeningeal thickening and spinal lesions. Biopsy from the spinal mass showed histomorphological features characteristic of DL-GNT. Further molecular analysis revealed 1p and 19q co-deletion andH3K27M mutation, while no mutation were identified inIDH, TERT, orBRAF genes. Patient died 4  months after diagnosis. Only one previous case of DL-GNT has been reported to harbourH3K27M mutation. AlthoughH3K27M mutations have been described in rare ...
Source: Brain Tumor Pathology - July 20, 2018 Category: Neurology Source Type: research

A surgical strategy for lower grade gliomas using intraoperative molecular diagnosis
In this study, we have developed a new surgical strategy for lower grade glioma based on the fourth edition of the World Health Organization Brain Tumor Classification, involving intraoperative molecular diagnosis. High-resolution melting analysis was used to evaluateIDH mutational status, while rapid immunohistochemistry of p53 and alpha-thalassemia/mental retardation syndrome X-linked (ATRX) was used to evaluate the 1p/19q codeletion status, allowing genetic classification during surgery. In addition, intraoperative flow cytometry was used to evaluate the surgical cavity for additional tumor lesions, allowing maximal res...
Source: Brain Tumor Pathology - July 6, 2018 Category: Neurology Source Type: research

Histopathological features to define atypical meningioma: What does really matter for prognosis?
This study investigated the ability of histopathological features t o predict recurrence risk of atypical meningiomas. Meningiomas classified as atypical only on minor atypical criteria had low recurrence risk. Brain invasion, high mitotic index and sheeting were significantly associated with shorter disease-free survival (DFS) (P = 0.001;P = 0.01;P = 0.01). The presence of brain invasion and the co-presence of sheeting and high mitotic index had the highest ability to identify recurring meningiomas (P = 0.0001) (sensitivity: 90.9%; specificity: 86.7%). Our results su...
Source: Brain Tumor Pathology - July 1, 2018 Category: Neurology Source Type: research

Importance and accuracy of intraoperative frozen section diagnosis of the resection margin for effective carmustine wafer implantation
AbstractFor effective implantation of carmustine (BCNU) wafers, it is important to determine the order of priority with reference to the intraoperative frozen section diagnosis of the resection margin (IOFM). The accuracy of IOFM and patterns of tumor recurrence with implantation of BCNU wafers were studied retrospectively. Forty-six cases of newly diagnosed malignant glioma were evaluated. Tumors were resected after intraoperative frozen section diagnosis (IOFD). IOFM was performed for resection walls and evaluated on a three-level scale ( −, no tumor invasion; 1+, minor cell invasion; 2+, evident cell invasion). Th...
Source: Brain Tumor Pathology - July 1, 2018 Category: Neurology Source Type: research

Paediatric diffuse leptomeningeal tumor with glial and neuronal differentiation harbouring chromosome 1p/19q co-deletion and H3.3 K27M mutation: unusual molecular profile and its therapeutic implications
We present a rare instance of a DL-GNT in a 13-year-old female who presented with slowly progressive and sequential neurological deficits over a 12-month duration. Imaging showed leptomeningeal thickening and spinal lesions. Biopsy from the spinal mass showed histomorphological features characteristic of DL-GNT. Further molecular analysis revealed 1p and 19q co-deletion andH3K27M mutation, while no mutation were identified inIDH, TERT, orBRAF genes. Patient died 4  months after diagnosis. Only one previous case of DL-GNT has been reported to harbourH3K27M mutation. AlthoughH3K27M mutations have been described in rare ...
Source: Brain Tumor Pathology - July 1, 2018 Category: Neurology Source Type: research

Impact of PCR-based molecular analysis in daily diagnosis for the patient with gliomas
AbstractThe WHO2016 CNS update requires a combined histological and molecular assessment. To assess the major aberrations such as co-deletion of complete chromosome arms 1p and 19q (Co-del), isocitrate dehydrogenase and histone H3 mutations, direct sequencing, multiplex ligation-dependent probe amplification and/or FISH are methods considered to be “golden standard” in the community. However, these methods are expensive and complicated. The aim of this study is verification of the sensitivity of the simple PCR-based techniques for assessment of molecular information in daily diagnosis. We analyzed a total numbe...
Source: Brain Tumor Pathology - July 1, 2018 Category: Neurology Source Type: research

A surgical strategy for lower grade gliomas using intraoperative molecular diagnosis
In this study, we have developed a new surgical strategy for lower grade glioma based on the fourth edition of the World Health Organization Brain Tumor Classification, involving intraoperative molecular diagnosis. High-resolution melting analysis was used to evaluateIDH mutational status, while rapid immunohistochemistry of p53 and alpha-thalassemia/mental retardation syndrome X-linked (ATRX) was used to evaluate the 1p/19q codeletion status, allowing genetic classification during surgery. In addition, intraoperative flow cytometry was used to evaluate the surgical cavity for additional tumor lesions, allowing maximal res...
Source: Brain Tumor Pathology - July 1, 2018 Category: Neurology Source Type: research

Radiological characteristics based on isocitrate dehydrogenase mutations and 1p/19q codeletion in grade II and III gliomas
In conclusion, IDH-Mut/Codel tumors were characterized by calcification, frontal location, heterogeneous signal intensity, and cortical invasion; IDH-Mut tumors differed from IDH-Wt tumors according to predominant frontal lobe location and less frequent dense enhancement patterns. (Source: Brain Tumor Pathology)
Source: Brain Tumor Pathology - July 1, 2018 Category: Neurology Source Type: research

A case of epidural glioblastoma metastasis presenting with a cervical myelopathy, torticollis, and L ’hermitte’s phenomenon
AbstractExtraneural glioblastoma metastases are exceedingly rare, though previously described in the literature. Activating mutations in theBRAF kinase gene (V600E) are present in a minority of glioblastoma patients. Here, we describe a case of systemic metastases of a clonal subpopulation ofBRAF V600E mutated glioblastoma in a patient previously treated with surgery, radiation, temozolomide and bevacizumab. The patient presented with a subacute cervical myelopathy during adjuvant treatment. He underwent emergent surgical decompression of an epidural spine metastasis. Analysis of the metastatic tumor demonstrated clonal ex...
Source: Brain Tumor Pathology - July 1, 2018 Category: Neurology Source Type: research

Stromal cells of hemangioblastomas exhibit mesenchymal stem cell-derived vascular progenitor cell properties
In conclusion, s tromal cells of hemangioblastomas exhibit mesenchymal stem cell-derived vascular progenitor cell properties. (Source: Brain Tumor Pathology)
Source: Brain Tumor Pathology - June 23, 2018 Category: Neurology Source Type: research

Impact of PCR-based molecular analysis in daily diagnosis for the patient with gliomas
AbstractThe WHO2016 CNS update requires a combined histological and molecular assessment. To assess the major aberrations such as co-deletion of complete chromosome arms 1p and 19q (Co-del), isocitrate dehydrogenase and histone H3 mutations, direct sequencing, multiplex ligation-dependent probe amplification and/or FISH are methods considered to be “golden standard” in the community. However, these methods are expensive and complicated. The aim of this study is verification of the sensitivity of the simple PCR-based techniques for assessment of molecular information in daily diagnosis. We analyzed a total numbe...
Source: Brain Tumor Pathology - June 21, 2018 Category: Neurology Source Type: research

Radiological characteristics based on isocitrate dehydrogenase mutations and 1p/19q codeletion in grade II and III gliomas
In conclusion, IDH-Mut/Codel tumors were characterized by calcification, frontal location, heterogeneous signal intensity, and cortical invasion; IDH-Mut tumors differed from IDH-Wt tumors according to predominant frontal lobe location and less frequent dense enhancement patterns. (Source: Brain Tumor Pathology)
Source: Brain Tumor Pathology - June 19, 2018 Category: Neurology Source Type: research

Importance and accuracy of intraoperative frozen section diagnosis of the resection margin for effective carmustine wafer implantation
AbstractFor effective implantation of carmustine (BCNU) wafers, it is important to determine the order of priority with reference to the intraoperative frozen section diagnosis of the resection margin (IOFM). The accuracy of IOFM and patterns of tumor recurrence with implantation of BCNU wafers were studied retrospectively. Forty-six cases of newly diagnosed malignant glioma were evaluated. Tumors were resected after intraoperative frozen section diagnosis (IOFD). IOFM was performed for resection walls and evaluated on a three-level scale ( −, no tumor invasion; 1+, minor cell invasion; 2+, evident cell invasion). Th...
Source: Brain Tumor Pathology - June 14, 2018 Category: Neurology Source Type: research

A case of epidural glioblastoma metastasis presenting with a cervical myelopathy, torticollis, and L ’hermitte’s phenomenon
AbstractExtraneural glioblastoma metastases are exceedingly rare, though previously described in the literature. Activating mutations in theBRAF kinase gene (V600E) are present in a minority of glioblastoma patients. Here, we describe a case of systemic metastases of a clonal subpopulation ofBRAF V600E mutated glioblastoma in a patient previously treated with surgery, radiation, temozolomide and bevacizumab. The patient presented with a subacute cervical myelopathy during adjuvant treatment. He underwent emergent surgical decompression of an epidural spine metastasis. Analysis of the metastatic tumor demonstrated clonal ex...
Source: Brain Tumor Pathology - May 9, 2018 Category: Neurology Source Type: research

The 2017 WHO classification of pituitary adenoma: overview and comments
AbstractThe fourth edition of the World Health Organization classification of endocrine tumors has been recently published. There are two critical changes to the classification for pituitary adenomas in this edition. One is that the term “atypical adenoma,” which was characterized based on highly proliferative properties to predict adenomas that carry a poor prognosis, was completely eliminated due to the lack of definitive evidence. The other change is the introduction of more precise cell lineage-based classification of pituit ary adenoma that is defined based on lineage-specific transcription factors and hor...
Source: Brain Tumor Pathology - April 23, 2018 Category: Neurology Source Type: research

Histopathological features to define atypical meningioma: What does really matter for prognosis?
This study investigated the ability of histopathological features t o predict recurrence risk of atypical meningiomas. Meningiomas classified as atypical only on minor atypical criteria had low recurrence risk. Brain invasion, high mitotic index and sheeting were significantly associated with shorter disease-free survival (DFS) (P = 0.001;P = 0.01;P = 0.01). The presence of brain invasion and the co-presence of sheeting and high mitotic index had the highest ability to identify recurring meningiomas (P = 0.0001) (sensitivity: 90.9%; specificity: 86.7%). Our results su...
Source: Brain Tumor Pathology - April 18, 2018 Category: Neurology Source Type: research