1/16. Co-existence of dual intracranial pathology clinical relevance of proton MRS.The co-existence of neuro-cysticercosis (NCC) and intracranial neoplasm in an individual is a rare entity. Atypical presentation of cerebral cysticercosis may mimic glioma, metastasis, cerebral abscess or vice versa. The dual existence of these two lesions have led to several postulates which may have clinical impact in due course of time i.e. NCC as an oncogenetic factor for glioma or similarity of antigen found in glioma and NCC etc. An adequate management of such cases poses a challenge to both imageologists as well as clinicians. Thus, a proper diagnostic evaluation is essential for successful management of such cases. MR spectroscopy (MRS), although still a clinical research tool, may be extremely useful for exclusion or confirmation of neoplastic lesions in such a clinical scenario. The findings of MRS in collaboration with imaging parameters may increase the diagnostic yield of a MR investigation. The authors encountered five cases of dual intracranial pathologies i.e. neurocysticercosis and glioma. MR spectroscopy was useful to arrive at a definitive diagnosis in such a situation.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
2/16. Atypical pleomorphic astrocytoma in the pineal gland: case report.OBJECTIVE AND IMPORTANCE: We report a rare case of pleomorphic astrocytoma in the pineal region that took a benign course despite pleomorphism. CLINICAL PRESENTATION: A 30-year-old woman suddenly developed right hemiparesis followed by loss of consciousness. A computed tomographic scan revealed a mass in the pineal region accompanied by obstructive hydrocephalus. Her symptoms improved after ventriculoperitoneal shunt surgery. INTERVENTION: The tumor was totally removed in an en bloc fashion using the occipital interhemispheric transtentorial route. light microscopy revealed that the tumor had marked pleomorphism and multinucleated, bizarre giant cells, but neither mitosis nor necrosis was seen. Glial fibrillary acid protein was immunohistochemically positive in a few tumor cells. Retinal soluble antigen was negative. No reticulin network between the tumor cells was observed. A histological diagnosis of atypical pleomorphic astrocytoma was made. CONCLUSION: No signs of recurrence have been observed for 7 years after surgery without adjuvant therapy. Histologically, the tumor resembled pleomorphic xanthoastrocytoma or pleomorphic granular cell astrocytoma, but the immunohistochemical findings were not completely compatible with either diagnosis. This benign astrocytoma in the pineal gland with unique features is the first such case reported.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
3/16. Pituicytomas, a mis-diagnosed benign tumor of the neurohypophysis: report of three cases.Pituicytoma is a rare benign primary tumor of the neurohypophysis, occurring in the sellar and suprasellar spaces. We report here three new cases with immunohistochemical and electron microscopic study. Particular attention was paid to the expression of some cell adhesion molecules. These tumors were characterized by bundles of elongated cells strongly immunoreactive to anti-vimentin, S-100 protein, neural cell adhesion molecule and neuron-specific enolase antibodies. glial fibrillary acidic protein (GFAP) was not recorded. It expressed the very late antigen alpha2 (VLAalpha2), but not VLAalpha5, and lacked epithelial markers expression (epithelial membrane antigen, E-cadherin), and specific neuronal markers (synaptophysin, chromogranin, neurofilament). Staining for pituitary hormones was negative. At the ultrastructural level, tumor/blood vessel basal lamina and cytoplasmic intermediate filaments were observed but desmosome or pericellular basal lamina were lacking. In one case few secretory granules were recorded. Differential diagnoses include granular cell tumors, pilocytic astrocytomas and spindle cell tumors such as solitary fibrous tumors, fibroblastic meningiomas and schwannomas. However, the unique pattern of antigenic expression and ultrastructural features of pituicytomas distinguish this rare tumor. As a subpopulation of pituicytes (which are distinctive glial cells of the neurophypophysis), some pituicytomas do not expressed GFAP. This suggests that pituicytomas presumably arise from pituicytes at various stages of their differentiation.- - - - - - - - - - ranking = 3keywords = antigen (Clic here for more details about this article) |
4/16. 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.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
5/16. A case of angioglioma composed of astrocytoma with a papillary growth pattern: immunohistochemical and ultrastructural studies.We report a case of a large cystic astrocytoma associated with arteriovenous malformation in the right cerebral hemisphere of a 16-year-old boy. neuroimaging showed large abnormal vessels with flow voids and arteriovenous shunt around the cystic lesion. Histologically, the cyst wall was formed by abnormal vasculature and clusters of glial cells forming a papillary growth pattern. The abnormal vasculature consisted of dilated vein-like vessels and medium-sized arteries with incomplete media, and was diagnosed as an arteriovenous malformation. Immunohistochemically, glial fibrillary acidic protein (GFAP) decorated both the perikaryon and the processes of the glial tumor cells. They were negative for epithelial membrane antigen (EMA), cytokeratin, and S-100 protein. Ultrastructurally, the tumor cells were rich in intermediate filaments, and neither cilia, microvilli, nor ependymal rosettes were verified. Based on these morphological features and the low MIB-1 labeling index of 0.8%, the glial tumor was diagnosed as astrocytoma, Grade II, according to the world health organization (WHO) tumor classification. An association of glioma with various types of vascular anomalies has been designated as angioglioma. A unique feature of the present case, however, is a papillary growth pattern, which is not listed in the current WHO classification of brain tumors. The recognition of the occurrence of such cases would be important in differential diagnosis of papillary ependymoma and choroid plexus papilloma.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
6/16. Pleomorphic granular cell astrocytoma of the pineal gland.BACKGROUND. Primary neoplasms of the pineal gland are uncommon. Two patients with unusual primary pineal tumors that had similar distinctive histologic features are reported. methods. The surgically resected neoplastic pineal tissue from these patients were examined by light microscopy, immunohistochemistry, and electron microscopy and correlated with the patients' clinical course. RESULTS. These pineal tumors consisted of a mixture of spindle-shaped cells with fibrillated cell processes and many large lipidized and/or granular pleomorphic cells, some of which were multinucleated. These two tumors superficially resembled pleomorphic xanthoastrocytoma and granular cell tumors of the central nervous system. The pleomorphic tumor cells expressed glial fibrillary acidic protein and some also produced retinal S-antigen, a marker for retinal photoreceptor cells. Long-term follow-up (8 years) on one of these patients suggested a relatively "benign" clinical course. CONCLUSIONS. It is possible that this newly described tumor may be a distinct subset of pineal gland neoplasias with a favorable biologic behavior despite the histologic features that would suggest otherwise.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
7/16. Combined treatment of pediatric high-grade glioma with the oncolytic viral strain MTH-68/H and oral valproic acid.The case of a 12-year-old boy with anaplastic astrocytoma of the left thalamus is reported. Postoperative irradiation and chemotherapy could not repress tumor progression; therefore, treatment was undertaken with an oncolytic virus, MTH-68/H, an attenuated strain of newcastle disease virus (NDV), and valproic acid (VPA), an antiepileptic drug, which also has antineoplastic properties. This treatment resulted in a far-reaching regression of the thalamic glioma, but 4 months later a new tumor manifestation, an extension of the thalamic tumor, appeared in the wall of the IVth ventricle, which required a second neurosurgical intervention. Under continuous MTH-68/H - VPA administration the thalamic tumor remained under control, but the rhombencephalic one progressed relentlessly and led to the fatal outcome. In the final stage, a third tumor manifestation appeared in the left temporal lobe. The possible reasons for the antagonistic behavior of the three manifestations of the same type of glioma to the initially most successful therapy are discussed. The comparative histological study of the thalamic and rhombencephalic tumor manifestations revealed that MTH-68/H treatment induces, similar to in vitro observations, a massive apoptotic tumor cell decline. In the rhombencephalic tumor, in and around the declining tumor cells, NDV antigen could be demonstrated immunohistochemically, and virus particles have been found in the cytoplasm of tumor cells at electron microscopic investigation. These findings document that the oncolytic effect of MTH-68/H treatment is the direct consequence of virus presence and replication in the neoplastic cells. This is the first demonstration of NDV constituents in an MTH-68/H -treated glioma.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
8/16. Soluble membrane antigens of brain tumors. I. Controlled testing for cell-mediated immune responses in a long surviving glioblastoma multiforme patient.A patient with glioblastoma multiforme survived 18 years after diagnosis and underwent 20 operations for extracranial metastasis. An immunologic survey of the patient was made over a 1-year-period using in vitro tests of lymphocyte responsiveness and skin tests with control and tumor antigens isolated from autologous and allogenic brain cell membranes. Two tissue-associated soluble cell membrane antigens also present in normal white matter, and two tumor-associated antigens (TAA) produce cell-mediated immune responses in patients with brain tumors. One of these tumor-associated antigens predominates in meningioma cells. In addition some low molecular weight components appeared, which seemed to be unique for the glioblastoma cells from the long-surviving patient.- - - - - - - - - - ranking = 8keywords = antigen (Clic here for more details about this article) |
9/16. Astroblastoma: electron microscopy and immunohistochemical findings: case report.The clinical, histological, immunohistochemical, and electron microscopic features of a cerebral astroblastoma are reported. The patient is a young woman with a superficial parietal tumor. Macroscopic findings include a well-delineated superficial nodule with a hard central core. Histological study disclosed a predominantly papillary tumor with hyalinized vessels. Tumor cells were scarcely positive with immunohistochemical stain for glial fibrillary acidic protein, extensive and diffusely positive with vimentin and neuron-specific enolase, and intensely positive with S-100 and epithelial membrane antigen in the papillary areas. Ultrastructural study showed abundant intermediate filaments forming bundles in tumoral cytoplasms, membrane junctions, and external laminae when cells were in contact with collagen fibers. Based on immunohistochemical and ultrastructural characteristics, we believe that the filaments seen in tumor cells are mainly vimentin filaments. These peculiar immunohistochemical patterns in a glioma may aid in the histological diagnosis of this rare tumor type.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
10/16. Does the pleomorphic xanthoastrocytoma exist? Problems in the application of immunological techniques to the classification of brain tumors.A case of a fibrous xanthomatous tumor of the meninges is reported. This is a rare tumor of childhood in which the characteristic pleomorphic histology contrasts with the good clinical prognosis. These tumors were reclassified as pleomorphic xanthoastrocytomas (PXA) due to their glial fibrillary acidic protein (GFAP) positivity. In the present tumor, GFAP was absent from nearly all cell bodies in most of the leptomeningeal regions of the tumor but could be detected with greater frequency at the cortical-leptomeningeal border zones and in the areas in which the tumor had infiltrated the cortex. All the tumor cells expressed vimentin and in, addition, most expressed alpha-1-antitrypsin, alpha-1-antichymotrypsin, tartrate-resistant acid phosphatase, common leukocyte antigen, and OKM1. This spectrum of marker staining corresponded not only to the pattern observed in two cutaneous fibrous histiocytomas and one malignant fibrous histiocytoma, but also to the results previously published in the literature with regard to fibrohistiocytic tumors. By contrast, this spectrum of monocytic-histiocytic marker staining was not seen in gliomas. We, therefore, regard the PXA as a mesenchymal tumor of the meninges, identical to benign fibrous histiocytomas elsewhere in the body. The possible reasons why this mesenchymal tumor can show GFAP positivity in the leptomeningeal border zone are discussed.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
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