Cases reported "Astrocytoma"

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1/49. Cerebellar astrocytoma associated with von hippel-lindau disease: case report with molecular findings.

    We describe the rare occurrence of a cerebellar astrocytoma developing in a patient with the von hippel-lindau disease. This tumour possessed well-differentiated fibrillated astrocytes and moderate vascular proliferation. Tumour cells were uniformly GFAP positive and negative for lipids. This tumour showed an A to C mutation at nucleotide 675 at the splicing donor site of exon 2 of the VHL gene and a concurrent loss of heterozygosity of the 3p25 locus, a site of allelic deletions reported in some astrocytomas. Allelic loci at 17q11, a site of common loss in pilocytic astrocytoma, however, were retained in this tumour. This case illustrates that astrocytomas are rarely found in the von hippel-lindau disease and they may contain genetic changes common to both haemangioblastomas and some astrocytomas.
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2/49. Cerebral granular cell astrocytomas: a Mib-1, bcl-2, and telomerase study.

    Granular cell (GC) astrocytoma is an uncommon variant of glioma that shares the cytologic features and high cytoplasmic lysosomal content with granular cell tumors elsewhere in the body. While the histogenesis and behavior of these neoplasms was originally in dispute because most were reported as single cases, the accumulated literature on approximately three dozen such lesions has now verified their usual astrocytic lineage and poor prognosis. Although the GC cell is thought to represent a degenerative process, little is known in these tumors about cell cycle regulation, as measured by Mib-1 and bcl-2 immunolabeling, or expression of other biomarkers of malignancy, such as telomerase. In our study, GC astrocytomas were similar to gemistocytic astrocytomas in their bland histology, often prominent perivascular lymphocytic cuffing and low Mib-1 labeling indices. Like gemistocytes, GCs appear to represent senescent, non-cycling cells. Absence of significant bcl-2 immunolabeling in our three cases, however, suggests that unlike gemistocytes, GC astrocytes develop senescence by mechanisms other than bcl-2 mediated apoptosis suppression. In one case in which frozen tissue was available for assay, we noted relatively high quantitative telomerase expression. The level paralleled that seen in other glioblastomas. Demise for our three patients occurred 3-25 months post-biopsy. Like gemistocytes, the presence of non-proliferative GCs signifies severe abnormalities in cell cycle regulation and maybe hallmarks of tumors with poor prognosis.
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3/49. Expression and localization of scatter factor/hepatocyte growth factor in human astrocytomas.

    Scatter factor/hepatocyte growth factor (SF/HGF) is a pleiotropic cytokine that has been implicated in glioma invasion and angiogenesis. The SF/HGF receptor, MET, has been found to be expressed in neoplastic astrocytes as well as in endothelial cells of the tumor vasculature. Both SF/HGF and MET expression have also been described to correlate with the malignancy grade of human gliomas. However, most glioblastoma cell lines lack SF/HGF expression, raising the question of the cellular origin of SF/HGF in vivo. Using in situ hybridization, we analyzed glioblastomas, anaplastic astrocytomas, diffuse astrocytomas, pilocytic astrocytomas, and normal brain for the expression of SF/HGF mRNA. We detected strong SF/HGF expression by the majority of the tumor cells and by vascular endothelial cells in all glioblastoma specimens analyzed. Combined use of in situ hybridization with fluorescence immunohistochemistry confirmed the astrocytic origin of the SF/HGF-expressiong cells. In contrast, CD68-immunoreactive microglia/macrophages, as well as vascular smooth muscle cells reactive to alpha-smooth muscle actin, lacked SF/HGF expression. In anaplastic, diffuse, and pilocytic astrocytomas, SF/HGF expression was confined to a subset of tumor cells, and signals were less intense than in glioblastomas. In addition, we detected SF/HGF mRNA in cortical neurons. SF/HGF expression was not up regulated around necroses or at tumor margins. MET immunoreactivity was observed in GFAP-expressing astrocytic tumor cells and endothelial cells as well as in a subset of microglia/macrophages. We conclude that in vivo, both autocrine and paracrine stimulation of tumor cells and endothelium through the SF/HGF-MET system are likely to contribute to tumor invasion and angiogenesis. Lack of SF/HGF expression by most cultured glioblastoma cells is not representative of the in vivo situation and most likely represents a culture artifact.
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4/49. Idiopathic polyneuropathy associated with cytotoxic anti-neuroblastoma serum. IgG and IgM immunoglobulin studies.

    Serums from six patients with progressive idiopathic acute or chronic polyneuropathy possessed a cytolytic activity against transformed mouse cholinergic or noncholinergic neuroblasts but not against transformed rat astrocytes. This activity was not qualitatively nor quantitatively present in serums from normal controls or from patients with a variety of other motor system disorders and other neurologic disorders. fluorescein conjugated goat antihuman IgG and IgM monospecific immunoglubulins were used to characterize further the cytotoxic activity from patient serums and these studies suggested the presence of immunoglobulin g (IgG) and immunoglobulin m (IgM) directed against a cell surface neuroblastoma antigen. Cold reactive immunoglobulins of the IgG and IgM type were present in the serums of all six patients. A bioassay is described that may be helpful in evaluating other patients with progressive idiopathic polyneuropathies.
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5/49. Malignant transformation of pleomorphic xanthoastrocytoma: case report.

    We report a case of a pleomorphic xantoastrocytoma which manifested itself as a cystic isodense lesion in the right fronto-temporal lobe in a 26 year-old woman. It appeared as a soft yellow tumor with cystic cavities on surgery. Five months after this surgery, the patient was submitted to a new operation, which revealed a friable tumor, easily differentiated from the normal parenchyma, with cystic components. The histopathological examination demonstrated pleomorphic xanthoastrocytoma with malignant transformation. Histologically, the tumor at first procedure was composed of pleomorphic astrocytes with multinucleated and foamy cells. A rare case of malignant transformation in pleomorphic xanthoastrocytoma is presented, discussed and illustrated in this paper.
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6/49. hemosiderin pigmentation of tumour cells in cerebellar pilocytic astrocytoma associated with post-traumatic hemorrhage in adults.

    The pilocytic astrocytoma is only rarely associated with gross intratumoral hemorrhage despite rich vasculature and blood vessel changes, accompanied often by perivascular depots of hemosiderin. We report an unusual case of pigmented cerebellar pilocytic astrocytoma presenting with posttraumatic hemorrhage in a 38-year-old man with no history related to the tumor. CT and MRI examination after head injury demonstrated unexpectedly the cystic lesion of 2 cm in diameter in the region of the right cerebellar hemisphere and vermis. The lesion was associated with hematoma and it was surgically removed 3 weeks after trauma. Histopathological examination revealed pilocytic astrocytoma tissue with broad hemorrhagic changes and with an unusual pattern of massive pigmentation of the cytoplasm of pilocytic astrocytes, consistent with hemosiderosis. Positive stains for iron and ferritin and ultrastructural study confirmed deposition of hemosiderin granules in the tumour cells. There was no evidence of melanin or melanosomes. This finding of hemosiderin accumulation in the cytoplasm of neoplastic astroglia seems to be analogous to post-hemorrhagic pigmentation of the normal Bergmann glia and subpial astrocytes. In the literature, the examples of neuroepithelial tumors with hemosiderin pigmentation of tumor cells have been rarely documented. To our knowledge, this is the first reported case of pigmented pilocytic astrocytoma exhibiting extensive intracellular hemosiderin deposition.
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7/49. Regression of grade III astrocytoma during the treatment of CML with imatinib mesylate.

    Astrocytomas are central nervous system neoplasms, which are derived predominately from astrocytes. On the basis of the histopathologic characteristics astrocytomas are graded from I to IV. The cells that demonstrate the greatest degree of anaplasia are used to determine the histologic grade of the tumor. The mean age of survival are approximately 10 years from the time of diagnosis for pilocystic astrocytomas (world health organization grade I), more than 5 years for patients with low-grade diffuse astrocytomas (WHO grade II), 2 to 5 years for those with anaplastic astrocytomas (WHO grade III), and less than 1 year for patients with glioblastoma (WHO grade IV). The treatment is a combination of surgery, radiation, and chemotherapy depending of the grade of astrocytoma. We present a case of 31-year-old man with grade III astrocytoma with subsequent chronic myelogenous leukemia treated with imatinib mesylate as part of his chronic myelogenous leukemia treatment failing to show recurrence of the astrocytoma 10 years after standard treatment for astrocytoma.
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8/49. Rod-shaped filamentous inclusions and other ultrastructural features in a cerebellar astrocytoma.

    A biopsy specimen of a cerebellar astrocytoma from a 14-year-old girl was studied by light and electron microscopy. Histologically the tumor showed a mixture of loose and compact areas with numerous Rosenthal fibers. By electron microscopy most tumor cells contained, besides the usual organelles, large amounts of 70 to 100 A thick filaments. Classical Rosenthal fibers were also identified. In addition many cell bodies and processes were sprinkled with fragments of Rosenthal fiber material. Ordered filamentous arrays (so-called Hirano bodies) were seen in a number of tumor astrocytes. They are considered to be a nonspecific arrangement of filament units largely devoid of cytopathologic significance. Other ultrastructural features of some tumor cells were inchoate forms of the granulated bodies of conventional histology, paired cisternal elements of rough endoplasmic reticulum, and honeycomb-like profiles of transversely cut cylindrical units of smooth endoplasmic reticulum. Microtubular bodies were numerous in the endothelial cells of the tumor vessels.
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9/49. Melanotic neuroectodermal tumors of the brain and skull.

    A case of melanotic neuroectodermal tumor in the cerebellum of a 21-year-old man is presented. Melanin was found mainly in small neoplastic cells rather than in large epithelioid cells. The tumor also contained neurons, as well as neoplastic tissue of ependyma, choroid plexus; and astrocytes. We propose that this neuroectodermal tumor resulted from a combination of cells originating in the neural crest and in the neural tube. The small cells have been described as medulloblasts, but they may be poorly differentiated ependymal cells, or, sympathicoblasts. The presence of pigment in these cells is compatible with an origin in the neural crest. The so-called melanotic progonoma, occurring most often in the maxilla of infants, is reviewed in relation to the melanotic neuroectodermal tumor of the brain. The tumor in facial bone occurs in adults as well as infants, in locations other than the maxilla, and has malignant forms. Melanotic neuroectodermal tumors, whether in brain or bone, are therefore similar in behavior as well as histologic appearance. The finding of similar tumors in these different locations is readily explained embryologically.
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10/49. Pleomorphic xanthoastrocytoma with desmoplastic reaction: angiomatous variant. Report of two cases.

    Two cases of cerebral pleomorphic xanthoastrocytomas (PXA-s) with prominent vascularity and desmoplastic changes occurring in young subjects are presented. The tumors displayed the marked pleomorphism characteristic of PXA-s and had variable cellularity. The cytoplasm of many tumor cells contained an abundance of lipid droplets. Most tumor cells were positive for glial fibrillary acidic protein. The unusual feature about these tumors was the presence of very large numbers of tiny blood vessels with variable thickness of their walls. In many areas the small vessels and the neoplastic astrocytes were in close proximity to each other, with capillaries adjacent to or protruding into tumor cell cytoplasm, reminiscent of the pattern seen in highly vascularized or "angiomatous" meningiomas. In other areas extensive fibrosis was seen. We feel that the latter, as in the cases of comparably vascular meningiomas, had its origin in congelation and secondary organization of plasma proteins that have exuded through leaky walls of newly formed blood vessels. These are the first reported cases of PXA with an angiogliomatous pattern.
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