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Low-grade Gliomas (low-grade + glioma)
Selected AbstractsNeurodevelopmental outcomes of children with low-grade gliomasDEVELOPMENTAL DISABILITIES RESEARCH REVIEW, Issue 3 2008M. Douglas Ris Abstract As a group, children with low-grade gliomas (LGGs) enjoy a high rate of long-term survival and do not require the intensity of neurotoxic treatments used with higher risk pediatric brain tumors. Because they are generally considered to have favorable neurobehavioral outcomes, they have not been studied as thoroughly as higher-grade brain tumors by late-effects researchers. In this article, we review the literature on the neurobehavioral effects associated with low-grade gliomas and conclude that, (1) this is a large, understudied group of survivors of pediatric brain tumors; (2) recent small- and large-scale studies document increased risk in multiple cognitive-behavioral domains after treatment for LGGs compared with healthy peers; (3) such risk is not uniform but varies with tumor location and treatments; and (4) a life span development perspective is essential to a complete understanding of the risks faced by these children. More research on the most efficacious biopsychosocial treatment models for improving the outcomes of survivors of low-grade glioma is recommended, informed by a better understanding of theireducational needs. Investigations of genetic influences on outcome as well as prospective studies of these patients as they age are also recommended. © 2008 Wiley-Liss, Inc. Dev Disabil Res Rev 2008;14:196,202. [source] Blood oxygenation level-dependent MRI of cerebral gliomas during breath holdingJOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 2 2004Yuan-Yu Hsu MD Abstract Purpose To assess the cerebrovascular responses to short breath holding of cerebral gliomas using blood oxygenation level-dependent (BOLD) magnetic resonance imaging (MRI). Materials and Methods Six patients with a low-grade glioma and one patient with a high-grade glioma were studied using T2*-weighted echo planar imaging (EPI) during repeated periods of 15-second or 20-second breath-holding. Tumor vascularity was evaluated using dynamic susceptibility contrast perfusion MRI. Results Increases in BOLD signal intensity during repeated breath-holding were consistently identified in patients' normal appearing gray matter, comparable with those in healthy adults. Absence of significant BOLD signal enhancement was noted both in low-grade and high-grade gliomas, which is either due to overwhelming hypoxia in a tumor, inadequacy or absence of hypercapnia-induced vasodilatation of tumor vessels, or both. Breath-hold regulated decreases in BOLD signals occurred only in the high-grade glioma, which is most likely due to the hypercapnia-induced steal effect that redistributes blood flow from tumor regions with unresponsive neovasculature to surrounding normal tissue. Conclusion BOLD MRI during short breath holding can disclose differential cerebrovascular response between normal tissue and cerebral glioma. J. Magn. Reson. Imaging 2004;19:160,167. © 2004 Wiley-Liss, Inc. [source] Carboplatin hypersensitivity reaction in pediatric patients with low-grade gliomaCANCER, Issue 4 2008A Canadian Pediatric Brain Tumor Consortium experience Abstract BACKGROUND. Carboplatin-based regimens have demonstrated activity in pediatric patients with low-grade glioma (LGG). However, carboplatin hypersensitivity reaction (Cb HSR) represents a common and limiting factor for the continuation of therapy. METHODS. The objectives of this study were to describe the prevalence, characteristics, and management of Cb HSR and to detail their impact on outcome. The authors conducted a comprehensive, national, retrospective review of children who were diagnosed with LGG between 1985 and 2004 and received treatment with carboplatin. RESULTS. One hundred five patients from 10 Canadian centers were included. The median patient age at diagnosis was 3.5 years (range, 0.3,16.8 years), and 33 patients (31.4%) had neurofibromatosis type 1. Carboplatin was administered monthly in 46 children and weekly in 59 children. Forty-four patients (41.9%) developed Cb HSR after a median of 10.5 infusions (range, 3,39 infusions). Cb HSR occurred significantly earlier among children on the weekly schedule (4.4 months vs 9.1 months; P = .02). The first allergic reaction was grade I or II in 36 patients (82%). The cumulative incidence of Cb HSR increased with the number of infusions, and there was no evidence of a plateau. The only predictive factor was being a girl rather than a boy (P = .02). Thirty-four of 44 patients with Cb HSR were re-exposed to carboplatin, and 24 of 34 patients (70.5%) had recurrent Cb HSR. A desensitization approach did not provide any advantage compared with premedication alone for altering Cb HSR. The median number of additional Cb infusions delivered was 4 (range, 0.5,34 infusions). The effect of Cb HSR on the 5-year progression-free survival rate was not statistically significant (P = .1). CONCLUSIONS. Forty-two percent of children with LGG who received carboplatin regimens experienced Cb HSR. Most rechallenged children had recurrent Cb HSR despite Cb HSR-altering regimens. Cb HSR did not have an impact on progression-free survival. Cancer 2008. © 2007 American Cancer Society. [source] Neurodevelopmental outcomes of children with low-grade gliomasDEVELOPMENTAL DISABILITIES RESEARCH REVIEW, Issue 3 2008M. Douglas Ris Abstract As a group, children with low-grade gliomas (LGGs) enjoy a high rate of long-term survival and do not require the intensity of neurotoxic treatments used with higher risk pediatric brain tumors. Because they are generally considered to have favorable neurobehavioral outcomes, they have not been studied as thoroughly as higher-grade brain tumors by late-effects researchers. In this article, we review the literature on the neurobehavioral effects associated with low-grade gliomas and conclude that, (1) this is a large, understudied group of survivors of pediatric brain tumors; (2) recent small- and large-scale studies document increased risk in multiple cognitive-behavioral domains after treatment for LGGs compared with healthy peers; (3) such risk is not uniform but varies with tumor location and treatments; and (4) a life span development perspective is essential to a complete understanding of the risks faced by these children. More research on the most efficacious biopsychosocial treatment models for improving the outcomes of survivors of low-grade glioma is recommended, informed by a better understanding of theireducational needs. Investigations of genetic influences on outcome as well as prospective studies of these patients as they age are also recommended. © 2008 Wiley-Liss, Inc. Dev Disabil Res Rev 2008;14:196,202. [source] Predicting the Histopathological Grade of Cerebral Gliomas Using High b value MR DW Imaging at 3-TeslaJOURNAL OF NEUROIMAGING, Issue 3 2008Juan Alvarez-Linera MD ABSTRACT BACKGROUND Our aim was to prospectively assess whether magnetic resonance (MR) diffusion-weighted (DW) imaging using high b values can predict better than b value of 1,000 s/mm2 the histopathological grade of cerebral gliomas. METHODS Fifty-four patients with histologically verified brain gliomas (35 high-grade and 19 low-grade gliomas) underwent MR DW imaging. Isotropic DW images and apparent diffusion coefficient (ADC) were obtained with b values of 1,000 and 3,000 s/mm2. Each tumor was evaluated as being hyperintense, iso-intense or hypointense to normal, contralateral-hemisphere white matter. RESULTS Most of the patients with high- and low-grade gliomas showed areas of increased signal intensity on their isotropic images, obtained with a b value of 1,000 s/mm2. However, with a b value of 3,000 s/mm2 the areas of increased signal intensity were seen in 97.1% of the high-grade gliomas, while 94.7% of the low-grade gliomas showed no area of increased signal intensity. The mean area under the ROC curve for ADC ratio, obtained with a b value of 3,000 s/mm2, was significantly higher than that obtained with 1,000 s/mm2 (.932 vs. .856, P= .04). CONCLUSION High b value DW MR might be useful as a complementary tool in preoperative assessment of the histopathological grading of cerebral gliomas. [source] Correlation of thrombospondin-1 and transforming growth factor-, expression with malignancy of gliomaNEUROPATHOLOGY, Issue 3 2000Tomoyuki Kawataki The expression of thrombospondin-1 (TSP-1) and its role in gliomas have not been well examined. In the present study TSP-1 expression in a panel of malignant glioma cell lines and the expression of TSP-1 and transforming growth factor (TGF-,) proteins in low-grade and malignant glioma tissues were investigated. Reverse transcription-polymerase chain reaction analysis showed that nine of nine malignant glioma cell lines expressed TSP-1 mRNA, and seven of nine glioma lines expressed TSP-2 mRNA. Production and secretion of TSP-1 were examined in the T98G glioblastoma cell line by western blot analysis. Total TSP-1 protein content in the supernatant was 10 times higher than that in the cell lysate. Secretion of TSP-1 was examined in these glioma cell lines by western blot analysis. All glioma lines secreted significant levels of TSP-1. Bioassay showed that all tumor lines had the capacity to activate latent TGF-,. Localization of TSP-1, TGF-,1, -,2, and -,3 was examined immunohistochemically in surgically resected glioma tissues, including 11 glioblastomas, six anaplastic astrocytomas, and eight astrocytomas. Most glioblastomas expressed high levels of both TSP-1 and TGF-,. Anaplastic astrocytomas expressed moderate levels of TSP-1 and TGF-,. Most malignant gliomas expressed various levels of TGF-,1, -,2, and -,3. The expression of both proteins, however, was weak in low-grade gliomas. Normal brain tissues around the tumors were negatively or very weakly positively stained for TSP-1 and TGF-,. These results indicate that most malignant glioma cells express TSP-1 in vitro and in vivo, and the expression of TSP-1 and TGF-,in vivo correlates with the histologic malignancy of glioma. Overexpression of both TSP-1 and TGF-, may increase the biologic malignancy of malignant gliomas, through generating the active form of TGF-, in tumor tissues. [source] Spectrum separation resolves partial-volume effect of MRSI as demonstrated on brain tumor scansNMR IN BIOMEDICINE, Issue 10 2008Yuzhuo Su Abstract Magnetic resonance spectroscopic imaging (MRSI) is currently used clinically in conjunction with anatomical MRI to assess the presence and extent of brain tumors and to evaluate treatment response. Unfortunately, the clinical utility of MRSI is limited by significant variability of in vivo spectra. Spectral profiles show increased variability because of partial coverage of large voxel volumes, infiltration of normal brain tissue by tumors, innate tumor heterogeneity, and measurement noise. We address these problems directly by quantifying the abundance (i.e. volume fraction) within a voxel for each tissue type instead of the conventional estimation of metabolite concentrations from spectral resonance peaks. This ,spectrum separation' method uses the non-negative matrix factorization algorithm, which simultaneously decomposes the observed spectra of multiple voxels into abundance distributions and constituent spectra. The accuracy of the estimated abundances is validated on phantom data. The presented results on 20 clinical cases of brain tumor show reduced cross-subject variability. This is reflected in improved discrimination between high-grade and low-grade gliomas, which demonstrates the physiological relevance of the extracted spectra. These results show that the proposed spectral analysis method can improve the effectiveness of MRSI as a diagnostic tool. Copyright © 2008 John Wiley & Sons, Ltd. [source] Development of a decision support system for diagnosis and grading of brain tumours using in vivo magnetic resonance single voxel spectraNMR IN BIOMEDICINE, Issue 4 2006Anne R. Tate Abstract A computer-based decision support system to assist radiologists in diagnosing and grading brain tumours has been developed by the multi-centre INTERPRET project. Spectra from a database of 1H single-voxel spectra of different types of brain tumours, acquired in vivo from 334 patients at four different centres, are clustered according to their pathology, using automated pattern recognition techniques and the results are presented as a two-dimensional scatterplot using an intuitive graphical user interface (GUI). Formal quality control procedures were performed to standardize the performance of the instruments and check each spectrum, and teams of expert neuroradiologists, neurosurgeons, neurologists and neuropathologists clinically validated each case. The prototype decision support system (DSS) successfully classified 89% of the cases in an independent test set of 91 cases of the most frequent tumour types (meningiomas, low-grade gliomas and high-grade malignant tumours,glioblastomas and metastases). It also helps to resolve diagnostic difficulty in borderline cases. When the prototype was tested by radiologists and other clinicians it was favourably received. Results of the preliminary clinical analysis of the added value of using the DSS for brain tumour diagnosis with MRS showed a small but significant improvement over MRI used alone. In the comparison of individual pathologies, PNETs were significantly better diagnosed with the DSS than with MRI alone. Copyright © 2006 John Wiley & Sons, Ltd. [source] Expression of Integrin ,v,3 in Gliomas Correlates with Tumor Grade and Is not Restricted to Tumor VasculatureBRAIN PATHOLOGY, Issue 3 2008Oliver Schnell MD Abstract In malignant gliomas, the integrin adhesion receptors seem to play a key role for invasive growth and angiogenesis. However, there is still a controversy about the expression and the distribution of ,v,3 integrin caused by malignancy. The aim of our study was to assess the extent and pattern of ,v,3 integrin expression within primary glioblastomas (GBMs) compared with low-grade gliomas (LGGs). Tumor samples were immunostained for the detection of ,v,3 integrin and quantified by an imaging software. The expression of ,v,3 was found to be significantly higher in GBMs than in LGGs, whereby focal strong reactivity was restricted to GBMs only. Subsequent analysis revealed that not only endothelial cells but also, to a large extent, glial tumor cells contribute to the overall amount of ,v,3 integrin in the tumors. To further analyze the integrin subunits, Western blots from histologic sections were performed, which demonstrated a significant difference in the expression of the ,3 integrin subunit between GBMs and LGGs. The presented data lead to new insights in the pattern of ,v,3 integrin in gliomas and are of relevance for the inhibition of ,v,3 integrin with specific RGD peptides and interfering drugs to reduce angiogenesis and tumor growth. [source] | ||||||||||