Modified rapid immunohistochemical staining for intraoperative diagnosis of malignant brain tumors
In this study, we tested the modified R-IHC by evaluating rapid immunostaining on new staining items in 94 brain tumor removal cases, which took place at Tokyo Women ’s Medical University from 2014 to 2015. The results showed that, based on GFAP and p53 markers, the modified method obtained a higher stability in specimens than the standard rapid immunostaining method. It also achieved stainability on the same level as that of a permanent specimen. The modified method tested 86.6% (46/53) and 82.8% (24/29) in pHH3 and ATRX, respectively, in the percentage of correct classification (PCC) against the permanent specimens, an...
Source: Brain Tumor Pathology - August 19, 2017 Category: Neurology Source Type: research
Expression of large neutral amino acid transporters LAT1 and LAT2 in medulloblastoma
(Source: Brain Tumor Pathology)
Source: Brain Tumor Pathology - August 16, 2017 Category: Neurology Source Type: research
Long-term epilepsy-associated tumor in the amygdala of a 16-year-old boy: report of a rare case having intranuclear filaments
AbstractThe term “long-term epilepsy-associated tumor (LEAT)” encompasses brain lesions associated with drug-resistant epilepsy over a long duration (≥2 years). Notably, some LEATs do not fit into any of the classifications of the World Health Organization (WHO). Herein, we report a LEAT that occurred in the left amygdala of a 16-year-old patient with intractable epilepsy. Histological examination of the resected amygdala revealed diffusely infiltrating tumor cells in the cortex. Perineuronal satellitosis and perivascular aggregation of tumor cells were apparent, along with mild nuclear enlargement and cytologic aty...
Source: Brain Tumor Pathology - August 10, 2017 Category: Neurology Source Type: research
Radiation-induced gliomas: a report of four cases and analysis of molecular biomarkers
The objective of this study was to investigate if commonly accepted glioma-specific biomarkers are relevant in RIGs. Among 269 gliomas diagnosed as WHO grade 2, 3 and 4 in our institution, four were diagnosed as RIGs. Immunohistochemical (IHC) staining for isocitrate dehydrogenase 1 (IDH1), p53, alpha thalassemia/mental retardation syndrome X-linked (ATRX), and H3K27M, and direct DNA sequencing ofIDH1/2, telomerase reverse transcriptase (TERT) promoter, Histone H3.3 (H3F3A) and B-Raf (BRAF) genes was performed. All tumor specimens were IDH1-, p53- and H3K27M-negative. The nuclei of tumor cells in all cases exhibited positi...
Source: Brain Tumor Pathology - August 9, 2017 Category: Neurology Source Type: research
Pericytes promote abnormal tumor angiogenesis in a rat RG2 glioma model
In this study, we performed morphological examinations to elucidate the possible involvement of pericytes in brain tumor vessel abnormalities using a rat RG2 glioma model. After implantation of RG2 glioma cells in the syngeneic rat brain, gliomas were formed as early as day 7. In immunohistochemical examinations, desmin-positive pericytes, characterized by morphological abnormalities, were abundantly found on leaky vessels, as assessed by extravasation of lectin and high-molecular-weight dextrans. Interestingly, desmin-positive pericytes seemed to be characteristic of gliomas in rats. These pericytes were also found to exp...
Source: Brain Tumor Pathology - June 23, 2017 Category: Neurology Source Type: research
Hemorrhagic ganglioglioma of the third ventricle with atypical pathological findings
(Source: Brain Tumor Pathology)
Source: Brain Tumor Pathology - June 17, 2017 Category: Neurology Source Type: research
Papillary thyroid carcinoma metastasizing to anaplastic meningioma: an unusual case of tumor-to-tumor metastasis
We present an unusual case of intracranial tumor-to-tumor metastasis inv olving papillary thyroid carcinoma (PTC) believed to have metastasized to an anaplastic meningioma (WHO grade 3). The patient is a 64-year-old female with a history of PTC, whose neuroimaging, performed as part of her staging workup, revealed a right parietal scalp lesion. The lesion was resected to reveal metastatic PTC with spindle cell component believed to represent sarcomatoid differentiation. Follow-up neuroimaging 2 months later revealed regrowth of the lesion under the previous craniotomy site. PET scan showed increased uptake in this area co...
Source: Brain Tumor Pathology - June 9, 2017 Category: Neurology Source Type: research
Histone H3 K27M mutations in adult cerebellar high-grade gliomas
AbstractAdult cerebellar high-grade gliomas (HGG) are rare and their molecular basis has not been fully elucidated. Although a diffuse midline glioma H3 K27M-mutant, a recently characterized variant of HGG, was reported to occasionally occur in the cerebellum, adult cases were rarely tested for this mutation; only five mutant cases have been reported to date. It currently remains unknown whether H3 K27M-mutant cerebellar gliomas share common histological features or have a uniformly dismal prognosis. In the present study, we assessed the prevalence of histone H3 K27M mutations in ten adult cerebellar HGG, identifying twoH3...
Source: Brain Tumor Pathology - May 25, 2017 Category: Neurology Source Type: research
Preface
(Source: Brain Tumor Pathology)
Source: Brain Tumor Pathology - April 28, 2017 Category: Neurology Source Type: research
Prevalence and clinicopathological features of H3.3 G34-mutant high-grade gliomas: a retrospective study of 411 consecutive glioma cases in a single institution
AbstractA recurrent glycine-to-arginine/valine alteration at codon 34 (G34R/V) withinH3F3A, a gene that encodes the replication-independent histone variant H3.3, reportedly occurs exclusively in pediatric glioblastomas. However, the clinicopathological and biological significances of this mutation have not been completely elucidated; especially, no such data exist for tumor samples from Japanese patients. We analyzed 411 consecutive glioma cases representing patients of all ages. Our results demonstrated that 14 patients (3.4%) harbored H3F3A mutations, of which four had G34R mutations and 10 had K27M mutations. G34R-mutan...
Source: Brain Tumor Pathology - April 26, 2017 Category: Neurology Source Type: research
Genetic aberrations and molecular biology of skull base chordoma and chondrosarcoma
In this report, we review the genetic aberrations and molecular biology of these two tumor types. Among the abundant genetic features of these tumors, brachyury immunohistochemistry and direct sequencing ofIDH1/2 are simple and useful techniques that can be used to distinguish between these tumors. Although it is still unclear why these tumors, which have such distinct genetic backgrounds, show similar histopathological findings, comparison of their genetic backgrounds could provide essential information. (Source: Brain Tumor Pathology)
Source: Brain Tumor Pathology - April 21, 2017 Category: Neurology Source Type: research
A case of glioblastoma resected immediately after administering bevacizumab: consideration on histopathological findings and safety of surgery
AbstractSurgery after administering bevacizumab should be carefully considered particularly because of wound healing concerns. A 27-year-old man presented with multiple tumor recurrences after gross total removal of a left temporal oligodendroglioma (1p/19q-noncodeleted). Whole brain radiotherapy with concomitant temozolomide and bevacizumab was immediately prescribed; however, the patient ’s condition deteriorated because of brain herniation. Three days after administering bevacizumab, an emergency tumor removal with external decompression and a ventriculo-peritoneal shunt was performed. The surgery and postoperative cl...
Source: Brain Tumor Pathology - April 20, 2017 Category: Neurology Source Type: research
Bevacizumab for malignant gliomas: current indications, mechanisms of action and resistance, and markers of response
AbstractVascular endothelial growth factor (VEGF) is an attractive target of antiangiogenic therapy in glioblastomas. Bevacizumab (Bev), a humanized anti-VEGF antibody, is associated with the improvement of progression-free survival and performance status in patients with glioblastoma. However, randomized trials uniformly suggest that these favorable clinical effects of Bev do not translate into an overall survival benefit. The mechanisms of action of Bev appear to include the inhibition of tumor angiogenesis, as well as indirect effects such as the depletion of niches for glioma stem cells and stimulation of antitumor imm...
Source: Brain Tumor Pathology - April 6, 2017 Category: Neurology Source Type: research
A novel all-in-one intraoperative genotyping system for IDH1 -mutant glioma
In this study, we established a rapid genotyping assay with a simple DNA extraction method, involving only incubation of the tumor specimen with Tris –EDTA buffer, which can be easily performed in an operating room. In all 11 tested cases, we could identify theIDH1 status within 90 –100 min intraoperatively. In a case of anaplastic astrocytoma, IDH-mutant, we could detect the tumor border byIDH1 profiling. In addition, with this assay, we could detectIDH1 mutation using cell-free tumor DNA derived from cerebrospinal fluid in a case of glioblastoma, IDH-mutant. Considering that clinical trials of mutated IDH1 inhibitor...
Source: Brain Tumor Pathology - March 28, 2017 Category: Neurology Source Type: research
A comprehensive review of paediatric low-grade diffuse glioma: pathology, molecular genetics and treatment
AbstractGliomas are the most common central nervous system neoplasms affecting children and can be both high- and low-grade. Paediatric low-grade glioma may be either World Health Organization grade I or grade II. Despite being classified as grade II diffuse astrocytoma, these neoplasms arising in children are distinct clinically and molecularly from their adult counterparts. They do not tend to progress to higher grade lesions and only rarely harbour an IDH mutation. Here, we review the clinical, histologic and molecular features of paediatric grade II diffuse glioma, highlighting their diagnostic criteria, prevalence acr...
Source: Brain Tumor Pathology - March 25, 2017 Category: Neurology Source Type: research
