1/125. A distinctive glioneuronal tumor of the adult cerebrum with neuropil-like (including "rosetted") islands: report of 4 cases.Four examples of a novel glioneuronal neoplasm are presented. All tumors affected adults (including two males and two females aged 25-40 years) as supratentorial, cerebral hemispheric masses with associated seizure activity and, in one case, symptoms of raised intracranial pressure and progressive hemiparesis. CT scans in two cases revealed hypodense masses without calcification. MRI scans at presentation demonstrated, in all cases, solid T1-hypointense and T2-hyperintense tumors with mass effect in one instance but no edema or contrast enhancement. Only one was relatively circumscribed on neuroradiologic study. All were infiltrative in their histologic growth pattern and predominantly glial in appearance, being composed mainly of fibrillary, gemistocytic, or protoplasmic astroglial elements of WHO grade II to III. Their distinguishing feature was their content of sharply delimited, neuropil-like islands of intense synaptophysin reactivity inhabited and rimmed in rosetted fashion by cells demonstrating strong nuclear immunolabeling for the neuronal antigens NeuN and Hu. These cells included small, oligodendrocyte-like ("neurocytic") elements as well as larger, more pleomorphic forms. Two cases contained, in addition, well-differentiated neurons of medium to ganglion-cell size. Proliferative activity was observed principally within the glial compartment; two cases contained mitotic figures and exhibited relatively elevated MIB-1 indices (6.8% and 8.2%). One of the latter progressed and proved fatal at 30 months following subtotal resection and radiotherapy. The three other patients are alive at intervals of 14 to 83 months, two tumor-free and one with extensive disease associated with the appearance of enhancement on MRI. This glioneuronal tumor variant may pursue an unfavorable clinical course.- - - - - - - - - - ranking = 1keywords = neoplasm (Clic here for more details about this article) |
2/125. Chordoid glioma of the third ventricle: confirmatory report of a new entity.The term "chordoid glioma" was recently introduced to denote a circumscribed, apparently low-grade neoplasm arising in or preferentially involving the third ventricle of middle-aged women. We report biopsy and postmortem findings in a 60-year-old woman with symptoms of forgetfulness, headache, and lethargy. neuroimaging showed a contrast-enhancing third ventricular mass with obstructive hydrocephalus. The tumor was subtotally resected. Microscopically, it consisted of clusters and strands of epithelioid cells in a mucoid matrix. Its margins were remarkably discrete and showed little tendency to infiltrate surrounding brain parenchyma. The majority of neoplastic cells were glial fibrillary acidic protein (GFAP) and vimentin positive, whereas S100 protein labeled only individual cells. Stains for epithelial membrane antigen (EMA) and cytokeratin were nonreactive. There was no evidence of neuroendocrine differentiation or expression of estrogen and progesteron receptors. Lymphoplasmacellular infiltrates were noted throughout the lesion and at the tumor-brain interface. The MIB-1 labeling index averaged 1.5%. At present, chordoid glioma is considered a glial neoplasm of uncertain histogenesis with distinct clinicopathologic features.- - - - - - - - - - ranking = 2keywords = neoplasm (Clic here for more details about this article) |
3/125. Chordoid glioma of the third ventricle: immunohistochemical and molecular genetic characterization of a novel tumor entity.Chordoid glioma of the third ventricle was recently reported as a novel tumor entity of the central nervous system with characteristic clinical and histopathological features (Brat et al., J Neuropathol Exp Neurol 57: 283-290, 1998). Here, we report on a histopathological, immunohistochemical and molecular genetic analysis of five cases of this rare neoplasm. All tumors were immunohistochemically investigated for the expression of various differentiation antigens, the proliferation marker Ki-67, and a panel of selected proto-oncogene and tumor suppressor gene products. These studies revealed a strong expression of GFAP, vimentin, and CD34. In addition, most tumors contained small fractions of neoplastic cells immunoreactive for epithelial membrane antigen, S-100 protein, or cytokeratins. The percentage of Ki-67 positive cells was generally low (<5%). All tumors showed immunoreactivity for the epidermal growth factor receptor and schwannomin/merlin. There was no nuclear accumulation of the p53, p21 (Waf-1) and Mdm2 proteins. To examine genomic alterations associated with the development of chordoid gliomas, we screened 4 tumors by comparative genomic hybridization (CGH) analysis. No chromosomal imbalances were detected. More focussed molecular genetic analyses revealed neither aberrations of the TP53 and CDKN2A tumor suppressor genes nor amplification of the EGFR, CDK4, and MDM2 proto-oncogenes. Our data strongly support the hypothesis that chordoid glioma of the third ventricle constitutes a novel tumor entity characterized by distinct morphological and immunohistochemical features, as well as a lack of chromosomal and genetic alterations commonly found in other types of gliomas or in meningiomas.- - - - - - - - - - ranking = 1keywords = neoplasm (Clic here for more details about this article) |
4/125. Osteolytic extra-axial sacral myxopapillary ependymoma.The authors report an unusual case of sacral osteolytic myxopapillary ependymoma treated with curettage and radiotherapy. There is no evidence of recurrence 8 years after treatment. A review of the literature is presented on sacral ependymomas presenting with an osteolytic radiographic appearance (24 cases in 18 reports). The differential diagnosis with other sacral neoplasms is discussed.- - - - - - - - - - ranking = 1keywords = neoplasm (Clic here for more details about this article) |
5/125. Intraspinal extradural myxopapillary ependymoma of the sacrum arising from the filum terminale externa. Case report.Extradural ependymomas of the sacrococcygeal region are very rare, with most arising from the soft tissues of the presacral area or from the regions dorsal to the sacrum. In even rarer circumstances, the tumor may arise within the sacral canal, likely as a result of ependymal cells of the extradural filum terminale. Because of bone erosion caused by extension of the tumor into the pelvis or dorsal to the sacrum, a truly intraspinal extradural ependymoma in this region has until now never been clearly demonstrated. The authors present a patient with a myxopapillary ependymoma arising from the filum terminale externa in which there was no involvement of the intradural filum or extension outside the sacral canal. A review of the literature is presented, with emphasis on the pathogenesis and clinical management of these rare tumors.- - - - - - - - - - ranking = 0.0026828019346016keywords = soft (Clic here for more details about this article) |
6/125. Adjuvant immunotherapy for malignant brain tumors in infants and children.Immune deficiency of immunocompetent cells or of humoral factors are essential causes of tumor growth. The authors have investigated the transfer of immunocompetent cells - allogeneic bone marrow cell transfusion and white blood cell intracranial infusion - for the treatment of 11 malignant gliomas in infants and children as an adjuvant to surgery, radiation and/or chemotherapy. Ten cases, from 3 months to 11 years, received bone marrow cell transfusion. Two medulloblastomas and 3 pontine gliomas are dead. Five cases are alive and well 37-65 months following surgery. Among these two posterior fossa neoplasms, a medulloblastoma and a glioblastoma have survived 46 and 65 months, respectively. One cerebral glioblastoma received allogeneic white blood cells infused locally into the tumor bed: it recurred 1 year following surgery, chemotherapy, and immunotherapy. Cytolysis of the tumor cells by sensitized lymphoid cells were demonstrated in this case. The role of immunotherapy should be limited at the present time to adjuvant therapy until its effect on tumor growth is statistically confirmed. The results so far are promising, and improvement of the immunological approach in treating malignant brain tumors is under way.- - - - - - - - - - ranking = 1keywords = neoplasm (Clic here for more details about this article) |
7/125. Integration of the metabolic data of positron emission tomography in the dosimetry planning of radiosurgery with the gamma knife: early experience with brain tumors. Technical note.The purpose of this study was to assess the use of positron emission tomography (PET) as a stereotactic planning modality for gamma knife radiosurgery (GKS). The authors developed and validated a technique for fiducial marker imaging, importation, and handling of PET data for integration into GammaPlan planning software. The clinical feasibility in applying this approach to a selected group of patients presenting with recurrent glial tumors or metastases was evaluated. Positron emission tomography data can be integrated into GammaPlan, allowing a high spatial accuracy, as validated using a phantom. Positron emission tomography data were successfully combined with magnetic resonance (MR) images to define the target volume for the radiosurgical treatment of patients with recurrent glioma or metastasis. This approach may contribute to optimizing target selection for infiltrating or ill-defined brain lesions. Because PET is also useful for the pretreatment and follow-up evaluation, the use of stereotactic PET in these patients can enable an accurate comparison of PET-based metabolic data with MR-based anatomical data. This could give a better understanding of the metabolic changes following radiosurgery. The ability to use PET data in GKS represents a crucial step toward further developments in radiosurgery, as this approach provides additional information that may open new perspectives for the optimization of the treatment of brain tumors.- - - - - - - - - - ranking = 0.0026828019346016keywords = soft (Clic here for more details about this article) |
8/125. Chordoid glioma: a novel tumor of the third ventricle.Chordoid glioma of the third ventricle is a recently characterized primary neoplasm of the central nervous system. We present a case and discuss the pathologic and radiologic features. We are aware of only 16 other cases documented in the world literature. This radiologic-pathologic correlation alerts pathologists and radiologists to recognize chordoid glioma as a distinct clinicopathologic entity restricted to the third ventricular area of adult patients.- - - - - - - - - - ranking = 1keywords = neoplasm (Clic here for more details about this article) |
9/125. Chordoid glioma of the third ventricle: an ultrastructural study of three cases with a histogenetic hypothesis.Chordoid glioma is a rare neoplasm occurring in the third ventricle and, as the name implies, having a chordoid appearance. It is currently considered a glial neoplasm of uncertain histogenesis with distinct clinicopathologic features. We report three cases of chordoid glioma with a focus on the ultrastructural appearance. The patients were two men and one woman aged, respectively, 34, 40, and 43 years. Immunohistochemically, all tumors showed strong and diffuse reactivity for glial fibrillary acidic protein and vimentin, whereas immunoreactivity for epithelial membrane antigen and cytokeratin was focal. Ultrastructurally, they showed features of ependymal differentiation for the presence of an apical pole with microvilli and a basal pole characterized, as in normal ependyma, by many hemidesmosomelike structures connecting cell membranes to the underlying basal lamina. Constant features were a submicroscopic cell body zonation (i.e., perinuclear, intermediate, subapical, and apical regions) and the presence of secretory granules. These findings were similar to those described for the secretory ependymal cells of the subcommissural organ, a small structure located in a dorsocaudal region of the third ventricle that undergoes regression after birth in humans. Our observations suggest that chordoid glioma may represent a subtype of ependymoma whose cells resemble the highly specialized ependyma of the subcommissural organ.- - - - - - - - - - ranking = 2keywords = neoplasm (Clic here for more details about this article) |
10/125. Pituicytoma: ultrastructural evidence of a possible origin from folliculo-stellate cells of the adenohypophysis.Pituicytoma is a rare neoplasm occurring in the sellar and suprasellar regions. The tumor is currently considered to arise from the pituicyte, a specialized glial cell of the posterior lobe and the stalk of the pituitary gland. The authors describe a case of pituicytoma, focusing on the ultrastructural features. The patient was a 79-year-old woman with hypopituitarism and visual disturbances. Immunohistochemically, the tumor showed strong and diffuse positivity for vimentin, and EMA and GFAP were focally detectable. Ultrastructurally, the lesion was composed of elongated cells containing in the Golgi area aggregates of intermediate filaments in a concentric pathway (fibrous body), and secretory granules. These features intermediate between a pituicytoma and a pituitary adenoma suggest that "pituicytomas" may also arise from the specialized stromal folliculo-stellate cells of the adenohypophysis, which are able to differentiate into endocrine cells.- - - - - - - - - - ranking = 1keywords = neoplasm (Clic here for more details about this article) |
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