Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0268596 (EMA)
 2,520 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Meningeal hemangiopericytomas (HPC) are rare CNS tumors with a pour prognosis compared to meningiomas. In order to define diagnosis criteria, we performed an immunohistochemical and ultrastructural study in respectively 15 and 5 meningeal HPC. The following antibodies anti-KL1, EMA, vimentin, CD34, factor VIII, alpha-smooth actin, estrogen and progesteron receptors (RE, RP) were used in paraffin embedded sections whereas anti-NCAM and E-cadherin antibodies were used on frozen sections when available. We can differentiate meningeal HPC from meningioma because of a complete lack of immunostaining with epithelial markers as well as with NCAM antibody or RE and RP receptors. Besides a positivity with CD34 and alpha-smooth actin antibodies was always observed even focally in HPC. On the other hand, solitary fibrous tumor showed a strong and diffuse positivity with anti CD34 and anti-vimentin antibodies. Electron microscopy can be helpful in some instances showing membrane basal-like substance and absence of desmosomes.
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PMID:[Contribution of immunohistochemistry and electron microscopy for the diagnosis of meningeal hemangiopericytomas. 15 case reports]. 1108 16

Presentation of a case of a "central type" neurofibromatosis in a 56-year old woman, clinically diagnosed erroneously as multiple sclerosis with a 20 years long course. Disturbances of hearing, walking, sight, sensitivity, incontinentia, intracranial hypertension and headache represented the main symptoms. More than 120 intracranial and tens of intraspinal meningiomas represented the leading postmortem finding. In a lesser frequency spinal plexiform neurofibromas and schwannomas were also found. The death was attributed to aspiration purulent bronchopneumonia. Various types of meningioma were seen microscopically, including secretory type and a type with amyloid. Immunostaining was positive with S-100 protein and EMA. Negative expression was found with vimentin, CEA, smooth muscle actin, estrogen and progesterone receptors, amyloid A and cytokeratins. With regard to the presence or absence of key morphological features the presented case was placed according to Sobol et al. (29) into the seventh category of neurofibromatosis (NF7).
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PMID:[Multiple intracranial and intraspinal meningiomas in the neurocristopathy (phacomatosis) type of neurofibromatosis]. 1137 7

A 74-year-old man manifested disturbed consciousness and right hemiparesis. Computed tomography revealed a left frontal parasagittal meningeal tumor with extensive peritumoral brain edema and skull invasion. Subtotal removal was performed. Five years later, he underwent two more operations of massive recurrences. Pathological studies revealed anaplastic meningioma with two different histological areas. One was an epithelial and meningothelial area, and the other was a papillary and rhabdoid area. In the papillary and rhabdoid area, small tumor cells with a high nucleus/cytoplasm ratio proliferated densely around the dilated central capillaries with a pseudopapillary pattern. Many rhabdoid cells (vimentin ++, cytokeratin AE1/AE3 +, epithelial membrane antigen [EMA] + +) tended to be distributed far from the central capillaries. There were many mitotic figures near the central vessels. Dense MIB1-positive nuclei were also observed near the central vessels. The trabecular pattern of the tumor cells in the epithelial area was quite different from the histological features of chordoid meningioma.
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PMID:Anaplastic meningioma with papillary, rhabdoid, and epithelial features: a case report. 1190 73

Solitary fibrous tumor is a mesenchymal neoplasm that most commonly arises in the pleura, but also in multiple extrapleural sites including, rarely, the meninges. Immunohistochemical findings facilitate its differentiation from other spindle cell lesions such as fibrous meningioma. Although the great majority of extrapleural solitary fibrous tumors behave in a benign fashion, only rare examples of brain-invasive tumors have been documented. We present a case of a brain-invasive solitary fibrous tumor arising in the meninges of a 40-year-old woman. The tumor was marked by focally prominent hypercellularity, moderate nuclear pleomorphism, and increased mitotic activity. Focal infiltration into the underlying brain parenchyma was observed. The tumor was CD34 positive and EMA negative.
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PMID:Brain-invasive solitary fibrous tumor of the meninges: report of a case. 1223 79

The purpose of this report is to describe the unique cytological findings of a new recently characterized type of meningioma that has extensive noncalcifying collagenous whorls and glial fibrillary acid protein (GFAP) expression. This new entity, described by Haberler and colleagues, was named whorling sclerosing variant of meningioma. The patient was a 34-yr-old white man with a large tumor in the brainstem. Intraoperative smear preparations showed a tumor with a large number of solid hyaline masses in a loose background and in focal areas tumor cells formed cohesive nests with a somewhat whorling appearance. The histological sections showed a neoplasia composed of innumerable eosinophilic, collagenous, noncalcified round deposits, cuffed by scattered meningothelial tumor cells. The neoplastic cells showed diffuse cytoplasmic reactivity for EMA and vimentin, as well as positivity to GFAP. This is the first cytological description of this new entity in the literature.
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PMID:Meningioma with extensive noncalcifying collagenous whorls and glial fibrillary acidic protein expression: new variant of meningioma diagnosed by smear preparation. 1272 24

Solitary fibrous tumor (SFT) is a mesenchymal neoplasm that has been recognized to occur almost all along the organism. Since its description in 1996 at the meninges, a total of 59 cases of meningeal SFT have been reported. Different authors have emphasized the difficulties in the differential diagnosis with other more frequent meningeal neoplasms such as meningioma or hemangiopericytoma, as the clinico-radiological characteristics of this lesion seem to be non specific and the morphological features on pathological study may resemble other spindle cell neoplasms. The diffuse and strong reactivity for CD34 and the negativity for EMA and S-100 are data allowing the diagnosis of SFT. We report the case of a 50-year-old woman suffering from headache, in whom MRI study showed a tentorial lesion initially thought to be a meningioma. In spite of morphological similarities with a fibrous meningioma, inmunohistochemical study finally led to the diagnosis of SFT. As occurred in previous cases, the findings in our patient reflect the similarities in clinico-radiological and pathological characteristics between meningeal SFT and other spindle cell meningeal neoplasms, mainly fibrous meningioma. When a clear diagnosis cannot be done based on typical findings on conventional hematoxylin-eosin study, inmunohistochemical study should be performed in meningeal spindle cell lesions to exclude SFT.
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PMID:Solitary fibrous tumor of the tentorium cerebelli. Case report. 1555 Aug 99

June 2004: Over the past year, this man in late-60s had complained about progressive weakness of concentration and memory disturbances, associated with word finding difficulties. MRI examination revealed an extra-axial, parasagittal tumor 3 cm in diameter located in the left frontoparietal region. Five years ago, a meningioma in the same region, with radiographic appearance comparable to the present tumor had been totally removed. The histological picture of the current tumor was dominated by sheets of large rounded pleomorphic tumor cells with abundant eosinophilic cytoplasm and eccentric nuclei (rhabdoid cells). Cytoplasmic inclusions were frequent; occasionally,multinucleatedtumorcellswereseen. Mitoticfigures were absent and the MIB was 3%. Meningothelial lobules were scarce, and regions with fibroblastic appearance were absent. There were no psammoma bodies, necrosis or brain invasion. Moderate immunoreactivity for EMA was found. Additionally, strong cytoplasmic immunoreaction for vimentin within the rhabdoid cells was observed. Review of the previous material showed small islets of rhabdoid cells. Rhabdoid meningioma is an uncommon meningioma variant. It has been suggested that rhabdoid meningiomas are highly aggressive tumors (WHO grade III)and that the rhabdoid phenotype represents a marker of malignant transformation in meningiomas. Histologically, rhabdoid meningiomas usually exhibit signs of anaplasia, a high mitotic activity, and a markedly increased MIB-1 labeling index. Extracranial metastases may occur in the course of the disease. However, not all rhabdoid tumors appear to have anaplastic features (as this case illustrates). Another interesting feature of rhabdoid meningiomas is that in a significant number of cases, the rhabdoid cells appear only at the time of recurrence. Alternatively, as seen in this case, the rhabdoid cells may be already present in the primary meningioma, but not as the predominating histological feature.
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PMID:June 2004: a male in his late 60s with recurrent extracerebral tumor. 1560 95

Although the histopathological subtypes of meningioma do not themselves appear to have prognostic significance, they are collectively important for defining the overall histopathological entity of microcystic meningioma (MCM) and allowing a distinction from other intracranial tumors, such as capillary hemangioblastoma, glioma, and metastatic renal cell carcinoma showing similar histology. Four cases of MCM were analyzed by conventional histology, immunohistochemistry, and electron microscopy. The present series of MCM was characterized by spindle- or cobweb-shaped tumor cells, characteristically associated small blood vessels, and a peculiar microcystic pattern. Among the microcystic meningeal tumor tissue, small areas of conventional subtypes were identified. Immunohistochemically, tumor cells showed the mesenchymal features of vimentin positivity and a rich distribution of matrix proteins around tumor cells. They lacked epithelial marker positivity but were faintly EMA positive. Ultrastructurally, primitive cellular junctions, desmosomes, and gap junctions were frequently seen between tumor cells. The gap junctions correlated with connexin 26 immunoreactivity. Although lacking an obvious epithelial nature, these features could be interpreted as showing an abortive differentiation mimicking meningothelial (arachnoidal) cells, which, physiologically, regulate cerebrospinal fluid between blood vessels and brain parenchyma.
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PMID:An ultrastructural and immunohistochemical study of microcystic meningioma with emphasis on matrix proteins and connexin 26 type gap junctions. 1569 36

Meningothelial hyperplasia is a poorly characterized entity, often associated with advanced age, chronic renal failure, trauma, hemorrhage, and neoplasia. In order to elucidate the nature of this lesion, 11 cases defined by the presence of nests of 10 or more cell layers thick, were compared with normal arachnoidal cap cells and meningiomas. Immunohistochemistry and FISH were performed to determine NF2 (merlin), protein 4.1B, EMA, progesterone receptor (PR), EGFR, survivin, VEGF, PDGF-BB, PDGFR-beta, E-cadherin, and cathepsin D status. All cases had at least one putative predisposing factor, including hemorrhage (7), chronic renal disease (5), old age (5), trauma (1), and an adjacent optic nerve pilocytic astrocytoma (1). There was typically a discontinuous growth pattern, with no invasion of surrounding normal tissue. No gene deletions were found, though scattered polyploid cells were seen in 2 cases. The immunoprofile was similar to normal cap cells with one exception; whereas normal cells were uniformly negative for PR, nuclear positivity was seen in 64% of hyperplasias, a frequency similar to that of benign meningiomas. Our data suggest that meningothelial hyperplasia is a reactive process that is usually distinguishable from meningioma based on clinicopathologic and genetic features. It may be preneoplastic in some, though further studies are needed to test this hypothesis.
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PMID:Meningothelial hyperplasia: a detailed clinicopathologic, immunohistochemical and genetic study of 11 cases. 1591 82

Meningiomas exhibit a broad spectrum of differentiation potency corresponding to different histological subtypes. The separate secretory or lipomatous transformation of meningothelial cells is uncommonly encountered in meningiomas classified into distinct secretory or lipomatous variants. The coexistence of these two different histological subtypes is extremely rare. We report an exceptional case of secretory meningioma associated with extensive lipomatous component in a 58-year-old woman. CT scan and MRI of the brain showed a well-defined tumor mass in the right temporal lobe with areas of adipose tissue and extensive surrounding brain edema. Microscopically, the tumor was composed of two components: whorls of meningothelial cells with numerous PAS-positive hyaline inclusions (pseudopsammoma bodies) and numerous mature adipocyte-like cells. The presence of neutral fat was confirmed by oil-red-O staining. The hyaline inclusions and tumor cells surrounding them showed strong immunoreactivity for EMA and CEA. Ultrastructural findings confirmed both secretory and lipomatous differentiation of tumor cells. The majority of lipidized neoplastic cells shared the features of meningothelial cells and adipocytes. Our result supports the opinion that lipomatous component ought to be considered as an advanced lipidization of neoplastic meningothelial cells rather than true metaplastic transformation of meningothelial cells into mature fat tissue. The present case of meningioma demonstrates a unique coexistence of secretory and lipomatous meningothelial components, reflecting the multipotency of phenotypic transformation of primary meningothelial cells.
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PMID:Meningioma with the unique coexistence of secretory and lipomatous components: a case report with immunohistochemical and ultrastructural study. 1686 3


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