Brain tumor pathology
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Brain tumor pathology · Jan 2018
Glioblastoma in neurofibromatosis 1 patients without IDH1, BRAF V600E, and TERT promoter mutations.
Pilocytic astrocytomas and low-grade gliomas are more common compared with glioblastomas in patients with neurofibromatosis 1 (NF1). A recent genome-wide analysis has shown frequent NF1 gene alterations in the mesenchymal subtype of a glioblastoma; however, little is known about clinicopathological features of glioblastomas in NF1 patients (NF1 glioblastomas). We analyzed four NF1 glioblastomas. ⋯ During the follow-up period, one patient died at 49 months and others remained alive for 60, 87, and 106 months; thus, patients with NF1 glioblastoma presented a relatively favorable survival. None of the NF1 glioblastomas harbored isocitrate dehydrogenase 1 (IDH1) gene mutation, v-RAF murine sarcoma viral oncogene homolog B1 (BRAF) gene mutation, and telomerase reverse transcriptase (TERT) gene promoter mutation. We identified that NF1 glioblastoma is a unique subset of glioblastoma.
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Brain tumor pathology · Jul 2016
Case ReportsReport of a rare case of atypical lymphoplasmacyte-rich meningioma in the tentorium mimicking idiopathic hypertrophic pachymeningitis.
A lymphoplasmacyte-rich meningioma (LPRM) is an extremely rare variant of meningioma. Here, we report a case of atypical LPRM with increased mitosis in a 55-year-old man. Preoperative magnetic resonance imaging suggested meningioma with brain invasion in the left tentorium cerebelli. ⋯ IgG4-RD was ruled out, because IgG4 counts and the IgG4:IgG ratio of plasma cells did not meet the diagnostic criteria for IgG4-RD. To date, only one case of LPRM with brain invasion has been reported as atypical LPRM. This case is therefore the second case of atypical LPRM with increased mitosis that histologically mimicked IHP.
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Brain tumor pathology · Apr 2016
Case ReportsEpithelioid/rhabdoid glioblastoma: a highly aggressive subtype of glioblastoma.
Epithelioid glioblastoma (GBM) and rhabdoid GBM are rare variants that are morphologically similar, but there is no consensus on the characteristics of each disease. These tumors have aggressive features of early recurrence and leptomeningeal dissemination and tend to develop in younger patients compared to typical GBM. The prognosis is normally worse than typical GBM, even with intensive chemoradiotherapy after surgical resection. ⋯ Two cases had a BRAF V600E mutation, whereas no ATRX mutation was present in any cases. All patients suffered leptomeningeal and/or spinal dissemination that worsened their prognosis. These results illustrate the need for a new therapeutic approach, such as molecular targeted drug therapy like BRAF inhibition, in addition to standard chemoradiotherapy for typical GBM.
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Brain tumor pathology · Jul 2015
Annexin A2 regulates angiogenesis and invasion phenotypes of malignant glioma.
We have established a pair of animal models (J3T-1 and J3T-2) with different invasive and angiogenic phenotypes, and demonstrated that annexin A2 is expressed at higher levels in J3T-1 than J3T-2 cells. The function of annexin A2 in relation to angiogenesis and invasion was investigated using these models. Stable silencing or overexpression of annexin A2 in J3T-1 and J3T-2 cells (J3T-1shA and J3T-2A cells) was established and used. ⋯ Positive expression of annexin A2 was observed in tumor cells surrounding dilated vessels in 25/30 human glioblastoma specimens. Our results reveal that the phenotype of glioma invasion is closely related to angiogenesis. We identify annexin A2 as a factor regulating angiogenesis and invasion of malignant gliomas.
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The cancer stem cell theory postulates that tumors are sustained by a select cell population with specific features, such as self-renewal ability and the capacity to give rise to a heterogeneous mass of tumor cells. The existence of such cells has been demonstrated for glioblastoma, with these cells being referred to as glioma stem cells (GSCs). ⋯ Furthermore, the lack of unequivocal markers for GSCs and a partial overlap in characteristics with other cells often lead to confusion. Here, we review the characteristics necessary for a glioma cell to be considered a stem cell, and we adopt our murine glioblastoma model based on genetically modified neural stem cells to illustrate and discuss the GSC concept.