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排序方式: 共有127条查询结果,搜索用时 15 毫秒
1.
颅内神经节细胞胶质瘤(附8例报告)   总被引:4,自引:1,他引:3  
目的探讨颅内神经节细胞胶质瘤的临床特征及治疗效果。方法回顾性分析8例颅内神经节细胞胶质瘤的临床资料。结果平均发病年龄27岁,肿瘤位于大脑半球6例,脑干2例。临床表现主要为癫,影像学检查无特异性表现。显微手术全切5例,大部切除3例,放、化疗4例。随访3个月~5年,7例症状明显缓解,1例复发。结论神经节细胞胶质瘤呈相对良性过程,癫为其主要临床表现,治疗上应手术全切;对有术后残留或间变者可给予放、化疗,预后相对良好。  相似文献   
2.
神经节细胞胶质瘤恶变及其差异表达基因分析   总被引:7,自引:3,他引:4  
目的探讨神经节细胞胶质瘤恶性进展的分子变化,为进一步研究分子病因奠定基础。方法取同一患者不断恶化的3次手术标本,行cDNA微阵列检测,分析在不同阶段持续存在的差异表达基因。结果初发(WHO II级)、复发(WHO III级)和再发(WHO IV级)的标本与正常脑组织相比,差异表达基因共19条,其中下调者16条,上调者3条。在下调的基因中,功能明确者有抑制RAF1/MEK/ERKs激酶通路激活的磷酸酰乙醇胺结合蛋白,抑制肿瘤血管增生、侵袭,调控细胞凋亡的碳酰还原酶;抑制c-myc基因表达的肺库否样因子;参与人DNA切除修复的多聚酶ε。结论神经节细胞胶质瘤恶变过程中持续存在的分子变化,以抑制肿瘤增殖基因表达下调为主,其中RAF激酶抑制蛋白、DNA多聚酶ε和碳酰还原酶是参与细胞信号传导和DNA损伤修复等具重要功能的基因,值得进一步研究。  相似文献   
3.
Differential Cellular Gene Expression in Ganglioglioma   总被引:1,自引:0,他引:1  
Summary:  Purpose:  Gangliogliomas (GGs) are neuronal-glial tumors highly associated with epilepsy. We hypothesized that the expression of select gene families including neurotransmitter receptor subunits and growth factors would be distinct in neurons and astrocytes within GG compared with adjacent cortex and that these changes would yield insights into seizure onset and lesion formation.
Methods:  Candidate gene expression was defined in single immunohistochemically labeled neurons and astrocytes microdissected from GG specimens compared with neurons and astrocytes microdissected from morphologically intact cortex adjacent to the GG or normal control cortex.
Results:  Differential expression of 16 genes including glutamate transporter (EAAC1) and receptor (NMDA2C, mGluR5), growth factor (hepatocyte growth factor), and receptor (platelet derived growth factor receptor β, fibroblast growth factor receptor 3) mRNAs was detected in GG neurons compared with control neurons. In astrocytes, altered expression of p75NGF, mGluR3, TGFβ3 and Glt-1 mRNAs was detected. Nestin mRNA, a gene that exhibits enhanced expression in balloon cell cortical dysplasia, was increased in GG neurons. Because of the morphological similarities between GG and cortical dysplasia, we show that there is activation of the mTOR cascade in GG as evidenced by enhanced expression of phospho-p70S6kinase and phosphoribosomal S6 proteins.
Conclusion:  We find differential candidate gene expression in neurons and astrocytes in GG compared with adjacent cortex and show that there is activation of the mTOR pathway. These changes highlight pathways that may be pivotal for epileptogenesis and lesion growth.  相似文献   
4.
Mixed dysembryoplastic neuroepithelial tumor and ganglioglioma   总被引:3,自引:0,他引:3  
We report a case of a 15-year-old girl with new onset seizures, who had a mixed dysembryoplastic neuroepithelial tumor (DNT) and ganglioglioma of the right parieto-occipital lobe. The tumor appeared well demarcated and exhibited a low T1 and a high T2 signal on magnetic resonance imaging. Architecturally it was in large part intracortical and multinodular, but also featured a leptomeningeal component. The former corresponded to DNT, a proliferation of oligodendroglia-like cells (OLCs) arranged in nodules, as well as comprising a diffuse internodular element featuring “floating neurons” in a mucoid matrix. The leptomeningeal portion of the lesion was a ganglioglioma consisting of large neurons and astrocytes in association with marked desmoplasia. Spacially, the two components abutted one another but appeared distinct. Immunohistochemistry showed the neurons of the ganglioglioma to be positive for class III β-tubulin, synaptophysin, and chromogranin A, whereas the astrocytic cells stained only for glial fibrillary acidic protein. Most OLCs in the DNT were positive for S-100 protein. This apparently mixed lesion suggests that a close histogenetic relationship exists between DNT and ganglioglioma. We postulate that the pluripotential progenitor cells residing in the subpial granular layer may have given rise to the cortical DNT and to the leptomeningeal ganglioglioma. To our knowledge, this is the first detailed histological, immunochemical and ultrastructural report of a mixed DNT and ganglioglioma. Received: 11 August 1997 / Revised, accepted: 24 November 1997  相似文献   
5.
Summary: Tumors and cortical dysplasia are associated with epilepsy, but few studies have examined the coexistence of neoplasia and dysplasia in these patients. We studied 13 patients (age 4–29 years) with recurrent seizures of 1 month to 21-year' duration (median 72 months). Ten patients were aged <21 years. Imaging studies localized the lesion to the temporal lobe (10 patients), parietal lobe (2 patients), and frontal lobe (1 patient). Tumors included ganglioglioma (8 patients), dysembryoplastic neuroepithelial tumor (DNT) (3 patients), and low-grade as- trocytoma (2 patients). Cortical dysplasia, including atypical aggregates of neurons (6 patients), multifocal loss of the cortical laminar architecture (7 patients), and neurons in the molecular layer of the cortex (3 patients) were observed near but separate from the tumor. Coexistence of certain tumors with cortical dysplasia, most frequently observed in the pediatric population, suggests a hamar-tomatous/dysplastic nature of the neoplasms.  相似文献   
6.
目的:分析儿童颞叶节细胞胶质瘤的临床和MRI特点。方法:回顾性分析9例经手术及病理证实为颞叶节细胞胶质瘤的临床及MRI资料。结果:病灶均位于颞叶内侧,位置较表浅,形态各异,边界多不清,以轻度水肿为主,占位效应表现为无占位、轻中度占位效应。9例中囊实性7例,实性2例,其中有钙化者3例,钙化呈短T1短T2信号,囊性呈长T1长T2信号,实性呈等T1稍长T2信号,FLAIR呈稍高信号,DWI实性部分呈等信号,ADC图呈等或稍高信号,强化方式多样,5例表现为无强化,1例轻度强化,1例中度强化,2例明显强化。最小ADC均值(0.97±0.11)×10-3mm2/s,ASL呈高等低灌注,MRS表现为NAA峰下降,与对侧正常区相比,节细胞胶质瘤的NAA/Cr比值降低,Cho/Cr和Cho/NAA比值增加。结论:对于顽固性癫痫患儿,MRI发现颞叶较表浅部位异常征象应考虑节细胞胶质瘤的可能性,以早期诊断提供准确治疗方案。  相似文献   
7.
Gangliogliomas are well-differentiated, slow-growing tumors. The majority are grade I of WHO. It appears predominantly in children and young adults. Most are located at the temporal lobe, and as symptomatology more frequent epileptic seizures of difficult pharmacological control. In general, they have a good prognosis after surgical resection. The anaplasic variant, considered to be grade III of the WHO, presents greater clinical and radiological aggressiveness. Leptomeningeal dissemination is exceptional in these types of tumors, but when diagnosed it presents a rapidly progressive and fatal course for the patient.  相似文献   
8.
目的探讨颅内节细胞胶质瘤(GG)所致癫痫患者的手术预后相关因素。方法回顾性分析我院2008年4月至2012年12月收治的5l例GG所致癫痫患者的临床资料。结果51例患者中68.6%(35/51)为药物难治性癫痫,72.5%(37/51)的患者肿瘤位于颞叶;70.6%(36/51)行肿瘤全切,29.4%(15/51)行次全切除。74.5%(38/51)患者合并局灶性皮质发育不良(FCD)。随访1。5年,84.3%(43/51)的患者癫痫达到EngelI级。肿瘤全切患者的癫痫缓解(EngelI级)率为94.4%(34/36),次全切的缓解率为60.0%,二者差异显著(P〈0.05)。结论GG通常为低级别肿瘤,手术全切除患者癫痫控制率较高;GG常合并FCD,为了取得更好的癫痫控制率,手术不仅要切除GG,也应将周围FCD切除。  相似文献   
9.
背景与目的:间变型节细胞胶质瘤非常少见,恶变总是发生在胶质成分。目前已有少量病例显示神经元成分的恶性转化。本文报道一例原发瘤为间变性节细胞胶质瘤,术后8个月复发为幕上原始神经外胚层肿瘤的病例。方法:观察并分析原发瘤和复发瘤的病理形态特征和免疫组化标记。结合文献讨论间变性节细胞胶质瘤转变为幕上原始神经外胚层肿瘤的可能机制。结果:患儿8岁。镜下见第一次切除的左颞叶肿瘤:部分区域肿瘤细胞密集分布。细胞较小,核染色较深,部分瘤细胞呈小片状,细胞稍大,核圆形或多角形,染色质淡。肿瘤组织中另可见散在或聚集向神经元分化的不同阶段的肿瘤细胞。细胞较大,有明显淡红染的胞浆,胞核空泡状,有核仁。有的似分化较成熟的节细胞。网状染色见瘤组织中纤维组织明显增生。免疫组化结果显示:GFAP灶性(+)、NSE(+)、S100(+)、Nestin(+)、VIM(+)、Des(+)。似神经元分化的大细胞则有NSE和S-100的阳性表达。病理诊断:伴有纤维增生的间变性节细胞胶质瘤。术后8个月左颞部复发肿瘤中除了仍见明显的纤维组织增生外,另见小或中等大小的肿瘤细胞密集排列,瘤细胞更异型,核分裂多见。未见较成熟分化的细胞。免疫组化显示:GFAP灶性(+)、S100(+)、NFP(+)、Neuronal class III beta-tubulin(+)。提示肿瘤细胞向神经元和胶质成分双向分化。病理诊断幕上原始神经外胚层肿瘤。结论:节细胞胶质瘤可以出现胶质和神经成分的恶性转化。  相似文献   
10.
Glioneuronal tumors of the central nervous system   总被引:9,自引:0,他引:9  
Advances in the immunohistochemical detection of neuron-specific and neuronal-associated antigens have resulted in the discovery of neuronal elements in certain primary human brain tumors. The results have been not only to expand what neuropathologists commonly recognize as gangliogliomas, including the tumors now known as glioneurocytic tumor with neuropil rosettes and papillary ganglioneuroma, but also to expand the spectrum of tumor types to now include tumors such as central neurocytoma, dysembryoplastic neuroepithelial tumor, and desmoplastic infantile ganglioglioma. These discoveries have helped us to better understand the biology of these tumors and to refine our classification of them. Distinctions among these tumors include sites of predilection, such as the temporal lobe with the dysembryoplastic neuroepithelial tumors, and a spectrum of clinical aggressiveness that spans indolent “quasihamartomatous” lesions, such as the dysembryoplastic neuroepithelial tumor, to high-grade, highly aggressive tumors, such as the supratentorial primitive neuroectodermal tumor (World Health Organization Grade IV). Many of these tumors also commonly exhibit a glial component, as determined by both their histologic appearance and their immunoreactivity for glial fibrillary acidic protein. This review covers these recently described lesions, including the desmoplastic infantile ganglioglioma, the dysembryoplastic neuroepithelial tumor, the papillary glioneuronal tumor, the glioneuronal tumor with neuropil rosettes, and the mixed glioblastoma-cerebral neuroblastoma (supratentorial primitive neuroectodermal tumor), as well as the known tumors, ganglioglioma, medulloepithelioma, and medulloblastoma. For pathologists confronted by this growing array of tumors and subtypes, it is appropriate to focus on them and understand the differential diagnosis to be considered when confronted by them.  相似文献   
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