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)

11 individuals were diagnosed to have neurofibromatosis type 1 and were examined for evidence of any ophthalmic lesions. Lisch nodules were the commonest manifestation of the disease and were present in 73% of all the patients (88% of those aged 16 years or more). 55% of the cases showed presence of neurofibroma on the lids. Other findings were optic glioma, unilateral sphenoid dysplasia with enlarged orbit, medullated nerve fibers and prominent corneal nerves with an incidence of 9% each.
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PMID:Involvement of the eye and orbit in neurofibromatosis type 1. 146 49

To characterize further the evolution of white matter lesions in neurofibromatosis type 1, we reviewed 68 MR images in 43 patients (age, 1-31 years), including 25 follow-up studies (mean interval, 27 months). Lesion number, location, morphology, signal characteristics, and contrast enhancement were assessed. Lesion characteristics and changes thereof were correlated with the patients' ages. Thirty-four patients (79%) had white matter lesions. These lesions were hyperintense on T2-weighted images, were isointense on T1-weighted images, and showed no mass effect or contrast enhancement in 31 patients; in three patients, T1-prolongation was observed (one with significant mass effect). None of the lesions evolved into a glioma. The most common locations were the cerebellum (49%), brainstem (22%), and internal capsule (19%). Nineteen patients had white matter lesions and follow-up studies. Lesions decreased in size or number in seven patients (average age, 13 years), showed no change in three (average age, 12 years), increased in size or number in four (average age, 5 years), and showed a mixed pattern (increased/decreased size/number) in four (average age, 7 years). White matter lesions in neurofibromatosis type 1 frequently increase in size or number early in childhood; this did not indicate neoplasia in our study. The lesions tend to resolve with increasing age. Lesion progression in a child more than 10 years old warrants close follow-up to rule out a neoplasm.
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PMID:Evolution of white matter lesions in neurofibromatosis type 1: MR findings. 160 92

Over a 24-year period, optic gliomas were found in 29 children, 16 of whom had neurofibromatosis type 1 (NF-1). These 16 children comprised 21% of all children referred for management of NF-1 and its complications. The finding of optic glioma led to the diagnosis of NF-1 in 4 children. The mean age at diagnosis of optic glioma in NF-1 children was 6.4 years, and the average estimated duration of visual symptoms prior to diagnosis was 2.1 years. Most optic gliomas in NF-1 children were ascertained because of a visual complaint (69%), and an even greater number of children (88%) had an abnormal ophthalmological examination. The optic chiasm was involved in 75% of the patients. All of the seven children with optic glioma examined by visual evoked potential had an abnormal response ipsilateral to the tumour. The majority of the children received radiation therapy. After a mean follow up period of 5.8 years no deaths had occurred due to optic glioma, but in 35% of the children vision was worse. We conclude that optic glioma is a common, serious complication in NF-1 children. Routine care of such patients should include regular noninvasive investigations aimed at detecting lesions of the optic pathway.
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PMID:Optic gliomas in children with neurofibromatosis type 1. 174 14

CT and MRI were used in a prospective study of the central nervous system (CNS) manifestations in 41 consecutive children with neurofibromatosis type 1 (NF-1). Gadolinium-DTPA was used in 15 patients. MRI was more effective than CT in delimiting the extension of the optic pathway glioma and in evaluating associated cerebral malformations. MRI visualized lesions generally undetected by CT, in the form of iso- or hyperintense foci with respect to the cerebral cortex in T2-weighted sequences. Well-delimited lesions of high signal intensity were observed in the globus pallidus (22 cases), the internal capsule (6 cases), corpus callosum (2 cases), anterior commissure (1 case) and semioval center (2 cases). Poorly defined hyper- or isointense areas were also observed affecting the cerebellar white matter (21 cases) and brain stem (17 cases). None of these lesions showed Gadolinium-DTPA enhancement, and were of no clinical significance. MRI has displaced CT in the initial diagnosis of patients with NF-1. Periodic annual MRI controls are only justified in patients with MRI changes to evaluate the progression or stabilization of the lesions.
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PMID:Imaging considerations of central nervous system manifestations in pediatric patients with neurofibromatosis type 1. 174 66

Recent efforts have been directed at identifying and characterizing candidate tumor suppressor genes and the activities of oncogenes in primary brain tumors. The p53 gene mapping to region p13 of chromosome 17 has several characteristics as a tumor suppressor gene. The wild-type p53 protein, which is a transcriptional activator, may serve as a barrier to the progression of neoplastic processes, and alterations of p53 are involved in genesis of various cancers including astrocytomas. The NF1 gene, which is responsible for the susceptibility to neurofibromatosis type 1, has recently been isolated. This gene is assumed to play a role in the signal transduction pathway by interacting with the ras gene product. Recent observation revealed that the NF1 gene may regulate the neuronal differentiation, and the alteration in regulation of the NF1 transcript is potentially related to the progression of neuroectodermal tumors. Restriction fragment length polymorphism studies have also shown chromosomal losses associated with chromosome 9, 10 and 17. These losses of genetic material are suspected to involve loci near or at the p53 gene for chromosome 17, and neighboring the interferon genes on chromosome 9. Although no sublocalization of chromosome 10 deletions has been accomplished, all of these loci are thought to harbor tumor suppressor genes. Recent advances in oncogene research have focused on understanding the mechanisms of action of growth factors, growth factor receptors, and their substrates, particularly in glial oncogenesis. Fibroblast growth factor, epidermal growth factor, and their respective receptors are of particular interest. However, the ROS oncogene, which is expressed and rearranged in some glioma cell lines, may not be a critical factor in the development of gliomas.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Pathways of oncogenesis in primary brain tumors. 190

We present a series of 31 cases of optic glioma associated with neurofibromatosis type 1 in patients under 11 years of age. They represent 64% of all the optic gliomas seen in our service between September 1965 and September 1993. The optic nerves were affected in 25 cases (83%); 9 children (30%) had a isolated, unilateral tumor; 16 (53%) had involvement of the optic chiasm as well as of one or both optic nerves. In 6 cases (19%) only the chiasm was affected, with or without involvement of other intracerebral structures. A coincidental orbital plexiform neurofibroma was associated with a poor prognosis. Other complications included 8 cases (26%) presenting with slowly developing aqueductal stenosis requiring treatment with a shunt. High-resolution computed-tomographic scans provided well-defined images for the diagnosis of optic nerve glioma, but magnetic resonance imaging was the preferred procedure for the diagnosis of gliomas involving the chiasm and the optic tracts and radiations, particularly if there was no mass effect. In our patients, tumor growth was hardly noticeable during follow-up even up to 20 years, with no difference between patients who were treated with radiation and those who were not treated. However, endocrine disturbances developed in all cases subjected to radiotherapy, and were less frequent in untreated patients. Aqueductal stenosis was observed with similar frequency among both treated or untreated patients. Three patients died, two due to complications of hydrocephalus secondary to aqueductal stenosis and one because of respiratory problems due to compression of the hypothalamus and brainstem by the chiasm tumor. Two of the 3 patients who died had orbital plexiform neurofibroma.
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PMID:Optic gliomas in neurofibromatosis type 1 (NF-1). Presentation of 31 cases. 802 21

Tumors of the central nervous system (CNS) are common causes of morbidity and mortality. These tumors can occur sporadically or in individuals with genetic disorders predisposing to cancer development. Such syndromes include neurofibromatosis type 2, neurofibromatosis type 1, Li-Fraumeni syndrome, as well as von Hippel-Lindau disease, tuberous sclerosis, and Turcot syndrome. There may also be familial syndromes resulting in glioma or meningioma alone, but these are not well understood. Development of sporadic gliomas is accompanied by a number of molecular genetic alterations, including activation of dominant oncogenes and inactivation of tumor suppressor genes. Some of these alterations may be associated with progression of gliomas to their most malignant form, glioblastoma multiforme. However, at this time molecular genetic analysis of gliomas does not provide better prognosis than histopathological staging. Recently, experimental treatments of gliomas in rodents, using gene therapy, have been reported. Results of these studies have been promising, and these techniques may represent a future direction for therapy in humans.
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PMID:Genetics, prognosis and therapy of central nervous system tumors. 802 96

We describe the clinical findings in 75 children with neurofibromatosis type 1 (NF-1, von Recklinghausen disease) diagnosed by the National Institute of Health criteria. The children were on average three years old at the time of their diagnosis. In 12 children complications of NF-1 were noted before diagnosis of their underlying condition, and half of the children had a serious complication, including intracranial tumour, optic glioma, scoliosis, pseudarthrosis tibiae, or mental handicap. Most complications of NF-1 occur before the age of ten. Therefore, and because of its severity and multifaceted presentation, children with NF-1 might benefit from follow-up in a multidisciplinary, specialized clinic.
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PMID:[Neurofibromatosis type 1 in children]. 806 37

We report the results of the reevaluation of 24 patients with neurofibromatosis type 1 (NF1) using central nervous system (CNS) imaging techniques. The first examination by computed tomography (CT) or magnetic resonance imaging (MRI) indicated the presence of optic glioma in three cases, "unidentified bright objects" (UBOs) in six, and a suspected right frontal tumor in one. In two patients optic glioma and UBOs were both present and in one of them a bulbar tumor was also suspected. Later imaging examinations revealed the appearance of optic glioma in three more cases and UBOs in nine. In two of these patients both optic glioma and UBOs were present. This study indicates that the likelihood of detecting imaging abnormalities in patients with NF1 increases when systematic follow-up is performed. Optic gliomas are characteristic of pediatric patients; they rarely give rise to clinical manifestations (1/6 cases) and in general progress very slowly. For these reasons, therapeutic strategy must be carefully considered and individually decided. UBOs are very frequent findings in pediatric patients with NF 1 and therefore they must be considered diagnostically relevant. They are not related to clinical manifestations and spontaneous regression has been observed. The nature of these imaging abnormalities is still unknown, but because they do not behave like tumors, useless and dangerous therapeutic procedures should not be employed.
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PMID:Central nervous system imaging in reevaluation of patients with neurofibromatosis type 1. 812 70

Inherited mutations of the p53 and neurofibromin genes are thought to cause two distinct neoplastic disorders in which gliomas occur, the Li-Fraumeni syndrome and neurofibromatosis type 1. We investigated the possibility that inherited mutations in specific regions of these genes also contributed to the clustering of gliomas in otherwise normal families. Twenty-six members of 16 families with glioma were screened for germline mutations of exons 5 through 9 of the p53 gene and exon 24 of the neurofibromin gene using a polymerase chain reaction-single-strand conformation polymorphism method. No germline mutations were found, suggesting that the genetic basis of familial glioma is distinct from that of gliomas occurring in the Li-Fraumeni syndrome, and that inherited mutations of the catalytic domain of neurofibromin do not predispose affected glioma families to these tumors.
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PMID:Absence of hereditary mutations in exons 5 through 9 of the p53 gene and exon 24 of the neurofibromin gene in families with glioma. 828 83


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