Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0017638 (glioma)
 30,880 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Pediatric brain tumors occur with a frequency of 24 to 27 cases/year within a cohort of 1 million children. Nearly 25% of these lesions will involve the cerebral hemisphere, with the low-grade glioma representing the most common group of tumors in this location. Pilocytic and fibrillary astrocytomas are the most frequently encountered glioma, although other variants, such as the ganglioglioma, pleomorphic xanthoastrocytoma, astroblastoma, ependymoma, and oligodendroglioma, must also be considered in the differential diagnosis. The etiology of these tumors remains obscure, although may be linked to therapeutic radiotherapy, previous history of hematopoietic malignancy and maternal exposure to nitrosamine-laden foods. An associated link to a phakomatosis, e.g., neurofibromatosis, tuberous sclerosis, has also been documented to exist with astrocytomas, in particular. The goals of surgery include a complete removal, in most circumstances, with an attempt to alleviate an associated seizure disorder when intractable. This is possible in nearly every type of hemispheric glioma with the aid of intraoperative navigational systems, i.e., frameless stereotaxy, neurophysiological based stimulation mapping, and electrocorticography. In the setting where a complete removal is possible, no further therapy is warranted. For those lesions that are incompletely resected, conservative management with routine diagnostic imaging follow-up is appropriate. Reoperation is necessary if recurrence is documented and radiotherapy is utilized for those lesions that are incompletely resected following recurrence.
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PMID:The impact of technical adjuncts in the surgical management of cerebral hemispheric low-grade gliomas of childhood. 883 58

During the time period 1990 to 1994 the mean incidence of pediatric brain tumors in Switzerland reached 2.78 new cases per 100,000 children under 16 years of age per year. In the same time period 33 children (18 male, 15 female) were newly diagnosed at the University Hospital of Berne with a tumor located in the posterior fossa. Ten (31%) had a medulloblastoma, nine (27%) an astrocytoma, six (18%) a brain-stem glioma, four (12%) an ependymoma, and four (12%) had other tumor types. Besides typical signs and symptoms of increased intracranial pressure, cranial nerve palsies or visual problems were frequently found (in 70% and 30% of the patients, resp.). The median time interval between the first symptoms and the definite diagnosis was four months. Central in the therapeutic approach remained the neurosurgical removal of the tumor, which was realized in 85% of the cases. As adjuvant weapons, radiotherapy and/or chemotherapy (in 45% and 48.5%, resp.) were used with curative aims. Globally 16 of the 31 evaluable children 51%) survived disease-free at the time of evaluation with a median survival of 42 months. The two-year survival rates were 83% for astrocytoma, 50% for ependymoma, 46.5% for medulloblastoma and 40% for brain-stem glioma. These observations emphasize the prognostic significance of histology in pediatric brain tumors.
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PMID:[Brain tumors of the posterior fossa in childhood. An overview of the patients of the medical university hospital's pediatric department Berne in the years 1990-1994]. 884 61

The role of inflammatory reactions in brain tumors is still unclear. In particular, there is little information about the participation of the microglia/macrophage cell system. We therefore investigated 72 surgical biopsy samples of brain tumors (astrocytoma, glioblastoma, oligodendroglioma, ependymoma, medulloblastoma, cerebral lymphoma, gangliocytoma, neurocytoma and germinoma) and the brains of eight cases with malignant gliomas that came to autopsy, using immunohistochemical markers for the monocyte/macrophage lineage (Ki-M1P, HLA-DR, KP1, My4, My7, Ki-M1, Ki-M6, EBM 11). These markers allowed us to characterize four subtypes of the microglia/macrophage cell system: ramified microglia, ameboid microglia, perivascular microglia and brain macrophages. Among the different tumors, glioblastomas and anaplastic gliomas showed the largest number of mixed cell populations, which consisted of macro-phages and ramified and ameboid microglia. In glial tumors of low malignancy fewer, predominantly ameboid, microglia were found. Neuronal tumors showed only a mild increase of microglia. Cerebral lymphomas contained macrophages diffusely distributed within the tumor center, while activated microglia were prominent at the border zone and in the adjacent brain tissue. The autopsy cases were used to study the morphometric distribution of microglia/macrophages. There was a significant increase of microglia/macrophages within the tumor, but no differences were seen between central and peripheral tumor areas. The non-neoplastic gray and white matter contained more microglial cells than controls. We conclude that the distribution pattern of ameboid and ramified microglial cells and macrophages is distinct in most of the investigated tumor types, underlining the complex immunological function of the microglia/macrophage cell system.
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PMID:Distribution and characterization of microglia/macrophages in human brain tumors. 887 Aug 31

Ependymomas are glial tumors of the brain and spinal cord occurring both sporadically and in a familial syndrome, neurofibromatosis type 2 (NF2). Previous analyses performed on specimens obtained predominantly from adult patients have shown loss of DNA sequences from chromosome arm 22q, which is the location of the NF2 gene. Previously, we documented the consistent loss of chromosome arm 17p DNA in medulloblastoma and astrocytoma, which are the most common brain tumors in children. Although mutation of the TP53 gene located on 17p is the most frequent genetic mutation in all adult tumor types, such mutations are rare in most childhood brain tumors investigated to date. We studied a series of pediatric ependymoma specimens (16 intracranial and 2 spinal) for loss of 17p and 22q DNA sequences and for mutation of the TP53 and NF2 genes. None of the children had the clinical stigmata of NF2. We detected loss of 17p DNA sequences in 9 of the 18 specimens (50%); in 7 of 9 of these specimens (78%), the 144-D6 marker was deleted. In contrast, only 2 of these same 18 specimens (11%) showed loss of 22q DNA. One TP53 gene mutation was detected in a child from a cancer kindred. No mutations were detected in the NF2 gene. Our results suggest that loss of chromosome arm 17p DNA sequences is common in sporadic pediatric ependymomas and that, in contrast to ependymomas in adults, deletion of chromosome arm 22q sequences is rare. Furthermore, TP53 and NF2 gene mutations do not play an important role in the etiology of sporadic pediatric ependymomas.
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PMID:Molecular genetic analysis of chromosome arm 17p and chromosome arm 22q DNA sequences in sporadic pediatric ependymomas. 888 5

The activity of the enzymes 5-formyl tetrahydrofolate cyclodehydrase and 5,10-methenyl tetrahydrofolate cyclohydrolase has been studied cytochemically in children's primary brain tumors. These enzymes play a significant role in purine biosynthesis. Thirty children, aged 1-12 years, were studied, 12 with medulloblastoma, 14 with glioma grade I-IV, and 4 with ependymoma. The activity of the enzymes was apparent as cytoplasmic granules that sometimes overlie the nucleus of the tumor cells. This coincidence showed that different types of brain tumors exhibit different degrees of enzymic activity, which in some cases correlated positively with the malignant potential of the tumor. Approximately one third of the cases were negative for any activity of these enzymes. The intensity of the staining of 5,10-methenyl tetrahydrofolate cyclohydrolase activity was actually higher than that of 5-formyl tetrahydrofolate cyctodehydrase. The clinical or prognostic significance of these findings remains to be clarified, but we believe that cylochemistry provides a sensitive technique for the detection, localization, and description of these enzymes in brain tumor cells. A clear understanding of the mode of action of these enzymes may contribute to devising novel therapeutic strategies.
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PMID:Activity of 5-formyl tetrahydrofolate cyclodehydrase and 5,10-methenyl tetrahydrofolate cyclohydrolase in primary brain tumors in children. 894 Jul 34

A 21-year-old woman was diagnosed with Turcot's syndrome (TS) at age 16 years. She had two ependymomas, one was located in the left middle cerebellar peduncle and the other in the low sacral spinal canal. Her mother and brother both had colectomies for colonic polyposis. Her maternal uncle and grandfather also had this disease and both died from cancer of the colon in their fourth decade of life. The patient was found to have hyperpigmented spots in the retina, skull osteomas and normal neurological examinations. The bone scan and CSF were normal and she had a germline mutation in the segment 3 of the adenomatous polyposis coli (APC) gene. Following partial resection of the two ependymomas, she was treated with radiation and chemotherapy. One year after surgery, paraspinal desmoid tumors were found and removed. She is presently 42 months postsurgical resection of the neural tumors and has remained central nervous system tumor-free. The occurrence of multiple ependymoma in TS has not been reported, and the control of this patient's ependymomas is consistent with other reports of long-term survival with TS and glial tumors.
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PMID:Multiple ependymomas in a patient with Turcot's syndrome. 895 Mar 38

Molecular genetic analysis of von Hippel-Lindau tumor suppressor gene (VHL gene) was performed on 38 tissues of human glial tumors (ependymoma, 1; astrocytoma, 6; oligodendroglioma, 1; oligoastrocytoma, 2; anaplastic oligoastrocytoma, 3; anaplastic astrocytoma, 14; glioblastoma multiforme, 11). Somatic DNAs extracted from frozen tumor specimens were examined by single-strand conformational polymorphism analysis and direct sequencing. In addition, loss of heterozygosity (LOH) on chromosome 3p in 15 glial tumor cases, lymphocyte DNAs of which were available, was examined by use of 10 microsatellite probes and two polymorphism markers for the VHL gene. Two cases of low-grade gliomas showed somatic sense mutations in exon 3 of the VHL gene, and 6 of 15 cases (40.0%) showed LOH of chromosome 3p. The VHL gene-mutated cases also showed LOH. The retention of heterozygosity and high pathological grade of glial tumors were correlated significantly. In addition, Kaplan-Meier survival analysis for patients with glial tumors showed that patients with LOH had a significantly longer survival time than those without LOH. These results suggest that somatic mutations on 3p, including the VHL gene, may be involved in tumorigenesis of some low-grade glial tumors.
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PMID:Somatic mutations of the von Hippel-Lindau tumor suppressor gene and loss of heterozygosity on chromosome 3p in human glial tumors. 906 65

We report a case of ependymoma with unusual vacuolar features arising in the left occipital lobe of a 2-year-old child. The tumor was composed of cells with single or multiple cytoplasmic vacuoles and clear cells. Some cells showed a signet ring-like configuration. Clear cells were compactly arranged and showed an oligodendro-glioma-like appearance. In addition, there were cellular ependymoma-like areas including perivascular pseudorosettes. On immunohistochemistry, glial fibrillary acidic protein and vimentin were mainly detected in cytoplasmic processes, and epithelial membrane antigen (EMA) staining showed granular and small vesicular reactivity. Ultrastructural investigation demonstrated intercellular microrosettes with or without cilia and long zonula adherens-type junctions that are typical of ependymoma. Furthermore, many intracytoplasmic lumina (ICL) were observed. Some ICL had microvilli and some did not. The latter varied in size, and may have fused with each other to develop giant ICL which could correspond to the signet ring-like configuration. Small ICL without microvilli had an appearance similar to that of distended endoplasmic reticula. Serial semithin and ultrathin sections revealed that EMA-positive structures were consistent with ICL containing microvilli and intercellular microrosettes. To determine the presence of unusual vacuolated ependymoma, electron microscopical examination was required. However, light microscopy was useful for detecting EMA-positive microvesicular and granular structures.
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PMID:An unusual variant of ependymoma with extensive tumor cell vacuolization. 908 65

Extraspinal ependymomas are a rare type of glioma that may arise in the sacrococcygeal region, presenting as a pelvic mass in an infant or child. Ependymoma presenting in the newborn period has not been described previously. Herein we describe a case of a newborn boy who presented with a perianal ependymoma, which was subsequently found to have presacral extension. The major diagnostic challenge this case presented was to rule out the alternative diagnosis of sacrococcygeal teratoma or a developmental malformation/heterotopia.
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PMID:Perianal ependymoma presenting in the neonatal period. 908 35

Pre-clinical data and adult experience suggests that topoisomerase targeted anti-cancer agents may be highly schedule dependent, and efficacy may improve with prolonged exposure. To investigate this hypothesis, 28 children with recurrent brain and solid tumors were enrolled in a phase II study of oral etoposide (ETP). Patients were prescribed ETP at 50 mg/m2/ day for 21 consecutive days. Courses were repeated every 28 days pending bone marrow recovery. Evaluation of response was initially performed after 8 weeks and then every 12 weeks either by CT or MRI. Three of 4 patients with PNET (primitive neuroectodermal tumor)/medulloblastora achieved a partial response (PR). Two of 5 with ependymoma responded, one with a complete response and one with a PR. Toxicity was manageable with only 1 admission for fever and neutropenia in 120 cycles of therapy. Five patients had grade 3 or 4 neutropenia. One had grade 4 thrombocytopenia and one grade 2 mucositis and withdrew as a result. One patient had grade 2 diarrhea. Two patients who achieved a PR had received ETP as part of prior combination chemotherapy regimens. Daily oral etoposide is active in recurrent PNET/medulloblastoma and ependymoma. Toxicity is manageable and rarely requires intervention. Daily oral etoposide in combination with crosslinking agents should be considered in future phase III trials. Determination of activity in glioma and solid tumors is not complete.
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PMID:Phase II study of daily oral etoposide in children with recurrent brain tumors and other solid tumors. 914 2


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