免疫组化技术对胶质瘤鉴别诊断的作用

用GFAP抗体对95例颅内肿瘤进行免疫组化染色,结果:全部75例星形细胞源性肿瘤和1例室管膜瘤呈阳性,其它胶质瘤和全部非胶质瘤呈阴性。认为GFAP是星形细胞源性肿瘤特异性标志物,它对形态变异的星形细胞源性肿瘤和混合性胶质瘤的鉴别诊断特别有用。星形细胞源性肿瘤GFAP染色的阳性程度与肿瘤的分化程度密切相关,因此GFAP染色对估计星形细胞源性肿瘤的分化和预后是有价值的。     

伸长细胞型室管膜瘤2例报道及文献复习

目的探讨伸长细胞型室管膜瘤的病理形态学特征。方法复习2例伸长细胞型室管膜瘤的临床病理资料，对手术切除的肿瘤组织，常规石蜡切片，HE染色，光镜观察，同时进行免疫组织化学标记GFAP、EMA、S-100蛋白、CKpan、Syn、CD34。结果例1位于腰2～3椎管内终丝，临床上主要表现出脊髓压迫症状，如运动及感觉障碍；例2发生于侧脑室，主要表现为头痛、呕吐、视物模糊。病理组织学上肿瘤富于细胞，排列成束状、交织状，细胞胞突细长双极，核异型性小，少数肿瘤细胞围绕血管周围形成室管膜瘤的无核区结构。免疫组化显示肿瘤细胞表达GFAP、EMA、CD99，而S-100蛋白阴性。结论伸长细胞型室管膜瘤是室管膜瘤的一种罕见亚型，病理诊断时尤其应注意与椎管内的神经鞘瘤和星形细胞瘤鉴别。     

胎儿侧脑室室管膜发育的免疫组织化学和电镜研究

目的：探讨胎儿脑发育过程中出现的放射状胶质细胞、伸展细胞和普通室管膜细胞之间的关系。方法：运用HE染色、免疫组化染色和电镜观察胎儿侧脑室室管膜组织。结果：12w时可见放射状胶质细胞和位于室管膜层的神经干细胞样细胞。少数放射状胶质细胞有单纤毛；20w时室管膜胶质纤维酸性蛋白(GFAP)呈阳性，伸展细胞出现在室管膜层；28w大量GFAP阳性的星状胶质细胞位于室管膜下层和中间层；以后GFAP阳性强度和细胞数开始下降。39w时GFAP阴性，无法见到伸展细胞。结论：放射状胶质细胞主要转变为星状胶质细胞，少量转化为普通的室管膜细胞。伸展细胞可能来源于神经干细胞，部份转化为普通室管膜细胞；部分可能转化为其他细胞，可能是室管膜瘤中伸展细胞的来源。     

伸展细胞型室管膜瘤的临床病理特点

目的：观察一少见的特殊类型室管膜瘤的临床病理特点,拟译名为伸展细胞型室管膜瘤。方法：复习3例此型的临床病理和免疫组化资料及有关文献。结果：3例肿瘤均位于脊髓内。它们的临床表现和放射影像学与室管膜瘤其他类型表现相同,病理形态学上,瘤细胞呈现双极的长梭形胶质细胞,形成不典型的血管周菊形团,GFAP、EMA弱阳性,而vimentin强阳性,而可与星形细胞瘤及神经鞘瘤相鉴别,其预后与其他类型室管膜瘤相类似。结论：由于肿瘤由双极、长梭形细胞组成。及tanycyte来源于tanyos有stretch伸出展开之意,“tanycytic ependymona ”以译成“伸展细胞型室管膜瘤”为妥。     

伴脂肪瘤分化室管膜瘤1例临床病理分析

目的：探讨伴有脂肪瘤分化室管膜瘤的临床病理学特征。方法对1例伴有脂肪瘤分化室管膜瘤行免疫组化SP法染色、PAS染色及网状纤维染色,并复习相关文献。结果镜下见肿瘤组织中除具有典型室管膜瘤结构和血管周围假菊形团外,还有多少不等、成片或散在的脂肪细胞。免疫表型：S-100、GFAP、EMA广泛强阳性,CK、NF均阴性。 Ki-67增殖指数较低(<2%),部分可达20%以上。特殊染色：PAS染色脂肪样细胞阴性,脂肪染色阳性。电镜下可见室管膜细胞典型结构。结论伴有脂肪瘤分化室管膜瘤在室管膜瘤结构基础上可见大量脂肪细胞,需与黄色瘤型室管膜瘤及伴有脂肪分化的其它颅内肿瘤鉴别。光镜观察结合免疫表型、特殊染色可资鉴别。     

垂体细胞瘤及其罕见室管膜样亚型的临床病理分析

目的探讨垂体细胞瘤及其罕见的室管膜样亚型的临床病理学特征和免疫表型、诊断和鉴别诊断。方法应用HE和免疫组化En Vision两步法染色观察7例垂体细胞瘤(6例经典型和1例室管膜样亚型)的组织学形态和免疫表型,并复习相关文献。结果镜下6例经典型肿瘤均由致密的肥胖梭形细胞构成,瘤细胞呈短束状和车辐状排列;而1例室管膜样亚型,瘤细胞呈漩涡状和乳头状排列,伴明显的血管周菊形团结构。免疫表型:所有肿瘤均弥漫表达S-100蛋白和TTF-1,而IDH1R132H、Olig-2、NF、CD34、Syn、Cg A及垂体激素均阴性,Ki-67增殖指数均2%。不同的是,经典型病例GFAP和EMA仅灶阳性,室管膜样亚型中GFAP呈弥漫阳性,且50%瘤细胞EMA点状阳性。结论垂体细胞瘤是起源于神经垂体细胞罕见的低级别胶质瘤,该实验有助于扩大垂体细胞瘤的形态学谱系和对新亚型的认识,对病理的鉴别诊断和临床治疗有益。     

RELA融合基因阳性室管膜瘤11例临床病理分析

目的探讨RELA融合基因阳性室管膜瘤的临床病理学特征。方法回顾性分析11例RELA融合基因阳性室管膜瘤的临床资料、影像学特点、病理学特征和免疫表型,并复习相关文献。结果 11例RELA融合基因阳性室管膜瘤均位于幕上,男性6例、女性5例,发病年龄3～56岁,平均27岁。影像学示幕上占位性病变。镜下见分支状毛细血管网和真/假菊形团结构。免疫表型:瘤细胞GFAP、L1CAM、Cyclin D1均呈弥漫阳性,EMA呈核旁点状阳性,多数病例表达nestin,Olig-2均阴性。结论RELA融合基因阳性室管膜瘤好发于年轻人的幕上,具有独特的免疫表型和基因表型,预后较差,需进行诊断与鉴别诊断。     

血管中心性胶质瘤1例并文献复习

目的探讨血管中心性胶质瘤(angiocentric glioma,AG)的临床病理学特征、免疫表型、预后及鉴别诊断。方法采用免疫组化法检测1例AG组织中EMA、GFAP、S-100、Ki-67、CD99、vimentin、NeuN、NF的表达,并复习相关文献。结果患者男性,24岁,伴有顽固性癫痫2年。肿物位于表浅额叶。镜下见瘤细胞在软脑膜-蛛网膜下呈平行流水状或垂直、栅栏状排列。瘤细胞是以皮质血管为中心的单形性单层或多层双极细胞,沿血管轴排列形成室管膜瘤样放射状或假菊形团样。瘤细胞核椭圆形、圆形或梭形,染色质点彩状。在神经实质内形成不同密度的瘤细胞区,包括致密纤维成分的实性生长区、栅栏状或漩涡状排列区、神经鞘瘤样结构区。瘤细胞表达GFAP、S-100,EMA核旁点状阳性,不表达NeuN、NF、Olig-2,Ki-67增殖指数1%。结论 AG是一种少见的与癫痫相关的WHO I级神经系统肿瘤,部位表浅,应与室管膜瘤、乳头状胶质神经元肿瘤、毛细胞型星型细胞瘤相鉴别。少数AG病例出现高增殖指数,核分裂象增多,形态间变或者伴有胶质母细胞瘤区等特点,属于不典型AG,应归入WHOⅡ级或更高级别。     

椎管内髓外硬膜下室管膜瘤1例并文献复习

目的探讨椎管内髓外硬膜下(intradural extramedullary, IDEM)室管膜瘤的临床病理特征、诊断及鉴别诊断。方法分析1例儿童多节段病变IDEM室管膜瘤的临床、病理及影像学资料,并复习相关文献。结果患儿女,8岁,颈段、胸段多发髓外占位性病变。镜下见肿瘤细胞呈假菊形团状排列,局部坏死,核分裂活跃。肿瘤细胞GFAP呈阳性,EMA呈灶阳性。肿瘤部分节段完整切除。结论发生于IDEM的室管膜瘤临床少见,尤其是儿童多节段病变IDEM室管膜瘤临床罕见。由于其特殊的发病部位,应根据临床、影像学特点、病理特征进行综合诊断。     

卵巢复发性播散性室管膜瘤1例并文献复习

目的探讨卵巢室管膜瘤的临床病理特征。方法对1例卵巢复发性、播散性室管膜瘤进行临床病理和免疫组化分析,并复习相关文献。结果患者42岁,体检发现左侧附件肿物6个月余入院。术中探查:盆腔及腹腔的腹膜表面散在结节状肿物种植,直径0.2～3 cm,子宫、双侧输卵管与盆壁粘连致密。镜检:肿瘤细胞丰富,细胞大小较一致,围绕血管,胞质突起朝向血管呈放射状,形成假菊形团样结构。免疫表型:GFAP、S-100、EMA、CK、vimentin、ER、PR阳性;病理诊断:原发性、复发性卵巢室管膜瘤。结论卵巢室管膜瘤是一种罕见的肿瘤,应该与卵巢上皮来源肿瘤、颗粒细胞瘤、未成熟畸胎瘤及神经内分泌癌相鉴别。     

Cytokeratin immunoreactivity in gliomas

Monoclonal antibodies (AE1/3, CAM 5.2 and PKK-1) and polyclonal antisera against the cytokeratin proteins were reacted with a range of astrocytic tumours, oligodendrogliomas and ependymomas. Seven of 12 cases (58%) of glioblastoma multiforme, five of eight (63%) anaplastic astrocytomas and two of five (40%) well-differentiated astrocytomas were immunoreactive with AE1/3 but not with the other anti-cytokeratin antibodies. In oligodendrogliomas, AE1/3 stained isolated astrocyte-like cells as well as scattered neoplastic oligodendrocytes in four of eight cases (50%) cases. Four ependymomas were negative for all cytokeratin markers examined. The immunostaining of astrocytomas and oligodendrogliomas with AE1/3 might represent co-expression of cytokeratin with glial fibrillary acidic protein by gliomas and calls for caution in the use of these antibodies in the differential diagnosis between gliomas and carcinomas.     

Astrocytes give rise to oligodendrogliomas and astrocytomas after gene transfer of polyoma virus middle T antigen in vivo

The cells of origin for oligodendrogliomas and astrocytomas are not known but are presumed to be oligodendrocyte and astrocyte precursors, respectively. In this paper we report the generation of mixed gliomas from in vivo transformation of glial fibrillary acidic protein (GFAP)-positive cells (differentiated astrocytes) with polyoma virus middle T antigen (MTA). MTA is a powerful oncogene that activates a number of signal transduction pathways, including those proposed to be involved in gliomagenesis, and has been shown to induce tumors in many cell types. We have achieved transfer of MTA expression specifically to GFAP(+) cells in vivo using somatic cell gene transfer, and find resultant formation of anaplastic gliomas with mixed astrocytoma and oligodendroglioma morphological features. We conclude that GFAP- expressing astrocytes, with appropriate signaling abnormalities, can serve as the cell of origin for oligodendrogliomas, astrocytomas, or mixed gliomas.     

Morphological maturation of tumor cells induced by ethylnitrosourea (ENU) in rat brains. I. On the tumors by administration of ENU in the late gestational stage

Sequential changes in the development of ethylnitrosourea (ENU)-induced rat brain tumors were examined histologically, immunohistochemically, electron microscopically and autoradiographically. In 47 Sprague-Dawley rats transplacentally administered ENU, 95 brain tumors developed, including 76 microtumors less than 1mm in diameter. Microtumors were found mainly in the paraventricular area, but some were found in the peripheral brain tissue. They were composed of small tumor cells which had round dark nuclei and scanty cytoplasm immunohistochemically negative for Leu 7 and glial fibrillary acidic protein (GFAP). The 19 macrotumors were mature gliomas, 3 of which histologically corresponded to oligodendrogliomas and 16 to mixed gliomas. The tumor cells of the former had small round nuclei with distinct perinuclear halos and a small amount of cytoplasm positive for Leu 7. The latter were chiefly composed of polygonal cells having large round nuclei and rich cytoplasm positive for GFAP. An autoradiographic study using 3H-thymidine revealed that the labeling index of the tumor cells was high in mixed gliomas and microtumors, but low in oligodendrogliomas. It may be concluded that the constituent cells of microtumors correspond to glioblasts or migrating neuroglias, which gradually mature to form oligodendrogliomas or astrocytomas.     

Uniform lineage of oligodendrogliomas.

Experimental observations provide evidence that galactocerebroside-containing (GC+) oligodendrocytes and glial fibrillary acidic protein-containing (GFAP+) type 2 astrocytes are derived from A2B5+ progenitor cells. Because the cytomorphologic features of oligodendrogliomas resemble those of non-neoplastic oligodendrocytes, it was speculated that neoplastic oligodendroglial cells also have A2B5+ lineage. This hypothesis was investigated by immunostaining histopathologic sections with monoclonal antibodies to GC, A2B5, and GFAP. In 28 tumors, ubiquitous immunolabeling of neoplastic cells with anti-GC and anti-A2B5 was observed. In addition, GFAP+/A2B5+ astrocytes were present in most mixed glial tumors. The findings suggest that oligodendrogliomas, whether or not they contain foci of astrocytoma, are uniformly derived from A2B5+ progenitor cells.     

Analysis of the NF2 gene in oligodendrogliomas and ependymomas

Allelic losses of chromosome 22 are commonly found in ependymomas and oligodendrogliomas, suggesting that at least one tumor suppressor gene on chromosome 22 must be inactivated during the multistep process of tumorigenesis in these glial tumors. The neurofibromatosis 2 gene (NF2) located at 22q12, is a candidate tumor suppressor gene potentially involved in the pathogenesis of gliomas. Because there have been only a few studies of the NF2 gene in glial tumors other than astrocytoma, we screened the entire 17 NF2 exons for mutations in a series of 47 nonastrocytic tumors, including 40 oligodendrogliomas and 7 ependymomas. Only one mutation was detected, a 59-base pair insertion in exon 3 from a spinal anaplastic ependymoma. These results concur with previous findings proposing preferential inactivation of the NF2 gene in a subgroup of ependymomas, and suggest that the NF2 gene is not the target of chromosome 22 aberrations in oligodendrogliomas.     

Expression of cytokeratins in gliomas

Metastatic carcinoma, which is a common malignant tumor seen in the central nervous system is often difficult to distinguish from glioblastoma multiforme. In general, neoplastic cells maintain fidelity in the expression of parent cell intermediate filament and immunohistochemistry remains the mainstay in diagnosis. A panel consisting of GFAP (usually positive for astrocytic tumors) and cytokeratin (usually positive for metastatic carcinomas) is most commonly used for this purpose. However, co-expression of two or more classes of intermediate filament proteins by neoplasms is a widespread phenomenon and there are reports of glial neoplasms expressing keratin markers. Our aims and objectives were to analyse the expression of both cytokeratin and GFAP in different glial tumors and metastatic carcinomas. Cases were collected for a period of two years. All the cases were diagnosed as primary or metastatic intracranial tumors. Formalin-fixed paraffin-embedded thin sections were taken on egg-albumin coated slides and immunostaining with GFAP and polyclonal cytokeratin was done. Forty-five tumors were analysed, including 35 glial neoplasms and 10 metastatic carcinomas of which 7 of the 32 astrocytic neoplasms (22%) showed focal immunoreactivity with pancytokeratin. All of the glial tumors but none of the metastatic carcinomas were positive with GFAP. So our conclusion was that co-expression of GFAP and CK is a fairly common phenomenon, especially in case of undifferentiated and high grade gliomas and this must be kept in mind while differentiating these cases from metastatic carcinoma, as CK positivity does not rule out the diagnosis of a glial neoplasm. Further studies with an expanded panel of CK is most useful for this.     

PDGF autocrine stimulation dedifferentiates cultured astrocytes and induces oligodendrogliomas and oligoastrocytomas from neural progenitors and astrocytes in vivo

We present evidence that some low-grade oligodendrogliomas may be comprised of proliferating glial progenitor cells that are blocked in their ability to differentiate, whereas malignant gliomas have additionally acquired other mutations such as disruption of cell cycle arrest pathways by loss of Ink4a-Arf. We have modeled these effects in cell culture and in mice by generating autocrine stimulation of glia through the platelet-derived growth factor receptor (PDGFR). In cell culture, PDGF signaling induces proliferation of glial precursors and blocks their differentiation into oligodendrocytes and astrocytes. In addition, coexpression of PDGF and PDGF receptors has been demonstrated in human gliomas, implying that autocrine stimulation may be involved in glioma formation. In this study, using somatic cell type-specific gene transfer we investigated the functions of PDGF autocrine signaling in gliomagenesis by transferring the overexpression of PDGF-B into either nestin-expressing neural progenitors or glial fibrillary acidic protein (GFAP)-expressing astrocytes both in cell culture and in vivo. In cultured astrocytes, overexpression of PDGF-B caused significant increase in proliferation rate of both astrocytes and neural progenitors. Furthermore, PDGF gene transfer converted cultured astrocytes into cells with morphologic and gene expression characteristics of glial precursors. In vivo, gene transfer of PDGF to neural progenitors induced the formation of oligodendrogliomas in about 60% of mice by 12 wk of age; PDGF transfer to astrocytes induced the formation of either oligodendrogliomas or mixed oligoastrocytomas in about 40% of mice in the same time period. Loss of Ink4a-Arf, a mutation frequently found in high-grade human gliomas, resulted in shortened latency and enhanced malignancy of gliomas. The highest percentage of PDGF-induced malignant gliomas arose from of Ink4a-Arf null progenitor cells. These data suggest that chronic autocrine PDGF signaling can promote a proliferating population of glial precursors and is potentially sufficient to induce gliomagenesis. Loss of Ink4a-Arf is not required for PDGF-induced glioma formation but promotes tumor progression toward a more malignant phenotype.     

Immunohistochemical study of ependymal neoplasms: histological subtypes and glial and epithelial characteristics

Summary An immunohistochemical study on ependymal tumours was performed in order to determine what relationships exist between histological subtypes and epithelial or glial characteristics. Thirty-eight ependymal tumours were examined with antibodies to cytokeratin (CK), epithelial membrane antigen (EMA), transthyretin (TTR) and glial fibrillary acidic protein (GFAP) using the avidin-biotin-complex technique. They included 23 ependymomas, 13 anaplastic ependymomas, and 2 myxopapillary ependymomas. Only 3 of the 23 ependymomas were positive with EMA but 19 reacted with GFAP. None of them were positive with CK. Six of the 13 anaplastic ependymomas were positive with EMA, 3 with CK and 10 with GFAP. Five of the 6 anaplastic ependymomas which had epithelial marker proteins were either negative or weakly positive for GFAP. The present study demonstrates that most benign ependymomas exhibit GFAP positivity while the anaplastic ones tend to suppress their glial nature in favour of epithelial differrentiation. However, ependymal tumours showed few characteristics of choroid plexus cells; only one of the examined cases was positive for TTR.