Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0017636 (glioblastoma)
 18,345 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The ultrastructural pathology of primary brain tumors of glial origin is examined. These are divided into two major groups. The first category comprises astrocytoma with the variants: fibrillary, protoplasmic, gemistocytic, and anaplastic. These are biologically aggressive tumors of a relatively high proliferative potential and include a substantial proportion of cases that transform into the most malignant secondary glioblastoma. The second category, comprised of rather benign tumors of a limited proliferative capacity and a reasonable good prognosis, includes such clinico-pathological entities as pilocytic astrocytoma, pleomorphic xanthoastrocytoma, and subependymal giant cell astrocytoma of tuberous sclerosis. There is no ultrastructural feature, however, which makes it possible to discriminate between major subclasses of astrocytes; but secondary glioblastoma cells, while still retaining the stigmata of neoplastic astrocytes, are characterized by nuclei that seem to be more indented, cisterns of the endoplastic reticulum may be distended, and intranuclear pseudoinclusions are frequently observed. Primary glioblastoma, which probably originates de novo, is characterized by poorly differentiated cells with a paucity of subcellular organelles and no obvious features of astrocytic origin. Granular cell tumor also belongs to neoplasms of astrocytic lineage and the hallmark of this entity is a cell characterized by the presence of numerous membrane-bound, electron-dense autophagic vacuoles. Its malignant analogue is the granular cell glioblastoma. Two subtypes of granular cell glioblastoma have been distinguished. The first is characterized by the presence of numerous granular, electron-dense bodies which correspond to autophagic vacuoles. The second type is characterized by numerous electron-dense, amorphous masses within cellular processes. These electron-dense inclusions are virtually indistinguishable from minute Rosenthal fibers. The pilocytic astrocytoma is virtually indistinguishable at the ultrastructural level from fibrillary astrocytomas but cells tend to be more elongated. Besides Rosenthal fibers, two types of distinctive structures are relatively common in pilocytic astrocytomas: eosinophilic hyaline droplets and round granular bodies, which are composed of large aggregates of electron-dense secondary lysosomes or small electron-dense bodies, respectively. Pleomorphic xanthoastrocytoma is characterized by astrocytes surrounded by basal membranes. It belongs to a peculiar category of astrocytic "desmoplastic" brain tumors occurring in younger patients, the common denominator for which is the presence of basal lamina. The last category in this group is subependymal giant cell astrocytoma, a tumor of bivalent (glial and neuronal) differentiation, the cells of which are characterized by the presence of peculiar crystalloids. The hallmark of oligodendroglioma is the presence of concentric arrays of membranes (so-called membrane laminations, whorls, or scrolls). A fragment of the cytoplasm sequestrated within a particular whorl may contain mitochondria, lysosomes, or abundant glycogen granules. Ependymomas are characterized by a florid picture dominated by the presence of microlumina, cilia with basal bodies (blepharoplasts), microvilli, and long, interdigitating intercellular junctions of the zonulae adherentiae type. Ganglioglioma, the last category covered by this review, is a mixed glio-neuronal tumor. While glial cells are indistinguishable from their counterparts encountered elsewhere (mostly pilocytic astrocytes), the ganglion cells are characterized by abundant intracytoplasmic dense-core vesicles, absence of intermediate filaments, and numerous microtubules. Occasionally a close apposition of ganglion cells and Rosenthal fibers is seen. Dense-core vesicles are pleomorphic and ranged in a diameter from small synaptic vesicles to large lysosome-like neurosecretory granules.
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PMID:Ultrastructural pathology of glial brain tumors revisited: a review. 902 63

Ganglioglioma is usually a well differentiated slowly growing mixed neuronal and glial neoplasm corresponding to WHO grade I or II. However, some gangliogliomas are considered to be WHO grade III because they exhibit anaplastic features in their glial component. Finally there are exceptionally rare cases of newly diagnosed gangliogliomas with grade IV changes in the glial component. We report a case of a 25-year-old woman with a family history of neurofibromatosis who presented initially with a World Health Organization grade IV anaplastic ganglioglioma (a mixed ganglion cell multiform tumor glioblastoma). Despite aggressive management, the patient died of disease in a relatively short period. Histologically, two cell populations were noted: a predominant glial component consisting in a multiform glioblastoma and ganglion cells supporting a diagnosis of ganglioglioma. Immunohistochemical analysis clearly distinguished the two tumor cell populations. Although other cases of grade III gangliogliomas and twelve cases of grade IV gangliogliomas have been reported, the present case is exceptional in that, to our knowledge, it is the second case of a patient who presented initially with a composite grade IV ganglioglioma and who was clinically followed up to the time of death. This case allows direct comparison between the histological findings in a multiform glioblastoma and a ganglioglioma. It also documents the aggressive biologic behavior of this complex neoplasm.
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PMID:[Malignant cerebellar ganglioglioma. A case report and review of the literature]. 1684 Sep 71

Ganglioglioma with a glioblastomatous component and high-grade atypia of neuronal cells are extremely rare findings. In this paper, we report the case of a 60-year-old man who presented with a tumor of the left temporal lobe. Hematoxylin-Eosin stained slides revealed a complex tumor with features of glioblastoma and marked atypia of neuronal cells. Glial cells were highlightened by antibodies to GFAP and neuronal cells by chromogranin and synaptophysin markers. There was an accumulation of p53-positive cells. There was a high Ki-67 labelling index (19%).
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PMID:Ganglioglioma with glioblastoma component. 1875 48

Ganglioglioma (GG) is an uncommon brain parenchymal neoplasm. Although most cases have indolent clinical behaviour, a subgroup of GGs does recur, especially in patients with unresectable disease. O6-methylguanine DNA methyltransferase (MGMT) is a DNA repair protein that removes mutagenic and cytotoxic adducts from O6-guanine in DNA. Lack of MGMT protein expression immunohistochemically is related to drug responses in patients with malignant glioma treated with alkylating agents. Furthermore, MGMT promoter methylation has also been investigated as an independent favourable prognostic factor for glioblastoma. The primary management is surgical resection for GGs and gross total resection is recommended. Despite infrequent use of chemotherapy for low-grade GGs, it was still introduced to a subset of patients, especially those who had unresectable disease. We assessed clinicopathological features of nine cases of low-grade GG to further elucidate the relationship between the status of the MGMT protein expression and the prognosis. This series included four men and five women with a mean age of 21.6 years at the first surgery. The mean postoperative follow-up period was 6 years. Only two patients had recurrent disease after 1.7 and 3.2 years of the first surgery. Immunohistochemically, 11.1% exhibited 3+ nuclear staining for MGMT protein, 11.1% exhibited 2+ staining, 33.3% exhibited 1+ staining, and 44.4% exhibited 0 staining. Tumours with more intensive MGMT protein expression (2+~3+ immunostaining) tended to recur more frequently (p < 0.05), corresponding to the worse prognostic predictive value of intensive MGMT staining.
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PMID:The prognostic impact of MGMT expression on low-grade gangliogliomas: a clinicopathological and immunohistochemical study. 2437 55