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)

A 45-year-old man with suspected recurrent malignant glioma was evaluated by magnetic resonance imaging (MRI), positron emission tomography (PET) and 131I labeled monoclonal antibody G-22 (G-22) scan. Following Gadolinium-DTPA, a TI-weighted spin echo image (TR 500 msec, TE 20 msec) demonstrated a large mass with an irregular margin in the left temporo-parietal area. An 18F labeled fluorodeoxyglucose PET study demonstrated marked accumulations in the left temporo-parietal area. Serial 131I-G-22 scintigraphy was obtained for a week after the injection. The uptake was most increased on the 2nd day after the injection. 131I G-22 was specific for tumor-associated antigens.
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PMID:Recurrent malignant glioma: detection with 131I labeled monoclonal antibody G-22, positron emission tomography and magnetic resonance imaging. 831 48

To date, magnetic resonance angiography (MRA) has been used in neuroradiology mainly to study vascular malformations and atherosclerotic changes of the carotid bifurcation. Our study was aimed at investigating the role of MRA with the time-of-flight technique in the study of intracranial neoplasms; a superconductive 1.5 T magnet was used, and FLASH and FISP 2D and 3D pulse sequences were acquired before and after Gd-DTPA administration. Fifty-five MRA examinations were performed. Our series consists in 32 meningiomas, 14 glial tumors, 3 hypophysis adenomas, 2 metastases, 1 NF2, 2 craniopharyngiomas, 1 lymphoma and 1 rhinopharyngeal carcinoma with intracranial involvement. In 27 patients MRA results were compared with DSA findings. The results showed high agreement relative to indirect angiographic patterns (dislocations, encasement, dural sinuses involvement) and poor accuracy in the demonstration of tumor vascularization (inflow and outflow, vascular neoformation).
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PMID:[Magnetic resonance angiography in the study of neoplastic cerebral pathology]. 848 47

The aim of this investigation was to assess the capacity of MR imaging to identify the tumour components of cerebral gliomas and thus to grade and delineate these tumours. A comparative analysis between MR examinations and histopathologic whole-brain sections was performed in 5 brain specimens from patients with malignant glial tumours. All cases were examined with MR imaging in vitro. In 2 cases a close comparison with the MR examination in vivo was also possible. The homogeneous hypercellular tumour core was not an isolated entity with typical signal characteristics in any sequence used. However, the tumour core was better observed in T2WI than in T1WI or PDWI, its signal characteristics both in vitro and in vivo being more hypointense than the peritumoural oedema. The use of image subtraction and T2 maps in combination with T2WI increased our capacity to correctly distinguish the most malignant part, compared with using each of these methods separately. In all cases, benign-looking tumour cells were found in the most peripheral aspects of the peritumoural oedema. These cells were not separately identified by any MR sequence or MR imaging method used. In 4 of the 5 cases of malignant glial tumours, we found isolated tumour cells and even larger tumour cell areas, though consisting of benign-looking cells, in areas that were visualized as normal in all sequences and MR imaging methods used. In all cases the necroses were heterogeneous. This heterogeneity was best reflected in the T2WI. Necroses were the most conspicuous tumour components in cases of malignant glioma and best reflected the underlying heterogeneous histopathology. A comparison between contrast-enhanced CT, Gd-DTPA-enhanced MR imaging and positron emission tomography (PET) with 11C-L-methionine was performed in 14 patients. In all patients except one, the area of increased 11C-L-methionine accumulation on PET, indicating viable tumour tissue, was the same size as, or larger than the extension of the contrast enhancement on both CT and MR. Contrast-enhanced MR and CT gave similar results as regards tumour extension. The increase in signal intensity 5 min post-contrast tended to be greater in the high-grade than in the low-grade tumour group. In order to evaluate the short- and long-term effects of formalin fixation on T1 and T2 of cerebral grey and white matter, MR imaging was also performed in 5 whole-brain specimens from patients with no known brain disease.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:MR imaging in cerebral gliomas analysis of tumour tissue components. 849 82

Brainstem gliomas are an important oncologic problem in the pediatric age group, constituting between 10 and 15% of childhood central nervous system neoplasms. A new classification scheme based on magnetic resonance imaging (MRI) has recently been proposed leading to speculation that gadolinium-DTPA-enhanced MRI may prove useful in defining the prognosis of subsets of patients with these tumors. We retrospectively reviewed gadolinium-DTPA-enhanced MRIs in 26 consecutive newly diagnosed pediatric patients (11 males, 15 females) from our institution between June 1988 and June 1994 with the diagnosis of diffuse brainstem glioma. The site, extent of invasion, T1 and T2 signals, and the pattern and the degree of contrast enhancement of the tumors were evaluated. We correlated the image features, clinical symptoms, and survival period in each patient. Seventeen tumors demonstrated contrast enhancement and 9 did not. The survival in the whole group ranged between 3 months and > 5 years with a median of 9 months. There was no statistical difference in the median survival between patients with or without contrast enhancement (11 versus 8 months).
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PMID:Prognostic value of contrast-enhanced magnetic resonance imaging in brainstem gliomas. 874 97

Recombinant human TNF-alpha was administrated intra-arterially to rats with transplanted intracerebral glioma. 1 x 10(6) of T9 rat glioma cells were transplanted into Fisher 344 rat brain stereotaxically and 1000 units of TNF-alpha was administrated at a rate of 100 microl/min. via an internal carotid artery 1 or 3 weeks after the transplantation. The effects of TNF-alpha were evaluated by MRI and histopathological examinations. Neurological symptoms, i.e. hemiparesis, appeared after 9.0 +/- 0.63 days and all rats died of tumor overloading 14.5 +/- 0.84 days after the transplantation. Single injection of TNF-alpha on 7th day after the transplantation induced regression of the tumor size in one of six rats. The tumors were detected 3 days after transplantation by MRI and they were revealed as low/iso intensity mass in T1WI, iso/high intensity in T2WI, and were enhanced by Gd-DTPA heterogeneously. On 7/14 days after the transplantation, the tumor grew approximately 7/10 mm in diameter. The single 1000 units of TNF-alpha were administrated via an internal carotid artery. 3 days after the administration of TNF-alpha, regression of the tumor size was seen in one of six rats and decrease of peritumoral edema was seen in three. These effects of TNF-alpha were, however, transient and they were not demonstrated on day 7. Single injection of TNF-alpha was not effective for large tumors more than 10 mm in diameter seen 14 days after the transplantation. These data suggest that intra-arterial TNF-alpha should be administrated at an early stage of the tumor growth and several injections are needed to cause regression in the size of the gliomas.
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PMID:[Antitumor effect of intra-arterial tumor necrosis factor-alpha in rats with transplanted intracerebral glioma and its evaluation by MRI]. 892 13

ATN-10, Mn-metalloporphyrin, has been developed as a tumor selective contrast agent for magnetic resonance (MR) imaging. To investigate the tumor specificity of ATN-10, we produced three experimental in vivo models; rat bran tumor (9L glioma) model, vasogenic (cold injury) and cytotoxic brain edema (24-hour MCA occlusion) models. The time course of contrast enhancement was compared after intravenous injection of ATN-10 or Gd-DTPA, measuring the signal intensity of the region of interest. After ATN-10 administration, the 9L glioma model showed early (5 min) and delayed (24 hr-) peak enhancement whereas the cold injury model showed only early enhancement and the 24-hour MCA occlusion model did not show significant enhancement. After Gd-DTPA administration, all three models showed similar pattern of only early enhancement. As a contrast agent for MR imaging, ATN-10 showed different behavior than Gd-DTPA in demonstrating the blood-brain barrier disruption and moreover ATN-10 showed selective enhancement in experimental brain tumors.
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PMID:Tumor specific contrast enhancement study of Mn-metalloporphyrin (ATN-10)--comparison of rat brain tumor model, cytotoxic and vasogenic edema models. 941 11

The goal of this study was to determine the magnitude of "facilitated" amino acid transport across tumor and brain capillaries and to evaluate whether amino acid transporter expression is "upregulated" in tumor vessels compared to capillaries in contralateral brain tissue. Aminocyclopentane carboxylic acid (ACPC), a non-metabolized [14C]-labeled amino acid, and a reference molecule for passive vascular permeability, [67Ga]-gallium-diethylenetriaminepentaacetic acid (Ga-DTPA), were used in these studies. Two experimental rat gliomas were studied (C6 and RG2). Brain tissue was rapidly processed for double label quantitative autoradiography 10 minutes after intravenous injection of ACPC and Ga-DTPA. Parametric images of blood-to-brain transport (K1ACPC and K1Ga-DTPA, microL/min/g) produced from the autoradiograms and the histology were obtained from the same tissue section. These three images were registered in an image array processor; regions of interest in tumor and contralateral brain were defined on morphologic criteria (histology) and were transferred to the autoradiographic images to obtain mean values. The facilitated component of ACPC transport (deltaK1ACPC) was calculated from the K1ACPC and K1Ga-DTPA data, and paired comparisons between tumor and contralateral brain were performed. ACPC flux, K1ACPC, across normal brain capillaries (22.6 +/- 8.1 microL/g/min) was >200-fold greater than that of Ga-DTPA (0.09 +/- 0.04 microL/g/min), and this difference was largely (approximately 90%) due to facilitated ACPC transport. Substantially higher K1ACPC values compared to corresponding K1DTPA values were also measured in C6 and RG2 gliomas. The deltaK1ACPC values for C6 glioma were more than twice that of contralateral brain cortex. K1ACPC and deltaK1ACPC values for RG2 gliomas was not significantly higher than that of contralateral cortex, although a approximately 2-fold difference in facilitated transport is obtained after normalization for differences in capillary surface area between RG2 tumors and contralateral cortex. K1ACPC, deltaK1ACPC, and K DTPA were directly related to tumor cell density, were higher in regions of "impending" necrosis, and the tumor/contralateral brain ACPC radio-activity ratios (0 to 10 minutes) were very similar to that obtained with 0 to 60 minutes experiments. These results indicate that facilitated transport of ACPC is upregulated across C6 and RG2 glioma capillaries, and that tumors can induce upregulation of amino acid transporter expression in their supporting vasculature. They also suggest that early imaging (e.g., 0 to 20 minutes) with radiolabeled amino acids in a clinical setting may be optimal for defining brain tumors.
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PMID:"Facilitated" amino acid transport is upregulated in brain tumors. 959 42

Multiple malignant gliomas are relatively uncommon, but are sometimes difficult to differentiate from multiple metastatic brain tumors. We analyzed the MR findings of four cases of multiple gliomas, comparing them with 12 cases of multiple metastatic brain tumors. All tumors were pathologically proven by surgical operation or autopsy. Gliomas were located in the deep white matter of the cerebrum, with none found in the posterior fossa. Tumors were relatively large, and irregular, thick, ring-like enhancement was noted after the administration of Gd-DTPA. Intratumoral hemorrhage was noted in only one case. High signal intensity on T2WI around the tumor suggested that edema was greater and more extensive than in metastatic tumors and was seen even in the corpus callosum. One autopsied case that showed this high intensity presented not only edema but also tumor infiltration. Metastatic tumors were located mainly in the corticomedullary junction of the brain. They were relatively small, and eight of 12 tumors showed, nodular or smooth ring-like enhancement. Intratumoral hemorrhage was noted in four cases. Edema was noted mainly around the tumor. We conclude that differential diagnosis between gliomas and metastases is possible to some extent by MRI.
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PMID:MRI findings of multiple malignant gliomas: differentiation from multiple metastatic brain tumors. 965 Aug 92

201Tl-SPECT was performed in 25 patients with a pathological diagnosis of glioma. The lesion-to-normal (L/N) ratio of the glioblastoma group (n = 7) was found to be higher than that of the low-grade glioma group (n = 7; Mann-Whitney U-test, p < 0.0167). 201Tl accumulation in the tumor corresponded to contrast enhancement on MRI in 95% of cases. An insufficient blood-brain barrier was considered to be the primary contributor to 201Tl accumulation. In five cases, there was a discrepancy between the extent of 201Tl accumulation and the Gd-DTPA enhanced area. In these cases, the area of 201Tl accumulation was larger than the area of Gd-DTPA enhancement. This may result from damage to the blood-brain barrier that is not severe enough to be detected with Gd-DTPA or from additional factors other than change in the blood-brain barrier. 201Tl-SPECT is able to demonstrate the extent of glioma more accurately than contrast-enhanced MRI.
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PMID:[Comparison of 201Tl-SPECT and MRI using Gd-DTPA for glioma]. 1045 85

We investigated whether the simultaneous use of paramagnetic contrast medium and 3D on-resonance spin lock (SL) imaging could improve the contrast of enhancing brain tumors at 0.1 T. A phantom containing serial concentrations of gadopentetate dimeglumine (Gd-DTPA) in cross-linked bovine serum albumin (BSA) was imaged. Eleven patients with histologically verified glioma were also studied. T1-weighted 3D gradient echo images with and without SL pulse were acquired before and after a Gd-DTPA injection. SL effect, contrast, and contrast-to-noise ratio (CNR) were calculated for each patient. In the glioma patients, the SL effect was significantly smaller in the tumor than in the white and gray matter both before (p = 0.001, p = 0.025, respectively), and after contrast medium injection (p < 0.001, p < 0.001, respectively). On post-contrast images, SL imaging significantly improved tumor contrast (p = 0.001) whereas tumor CNR decreased slightly (p = 0.024). The combined use of SL imaging and paramagnetic Gd-DTPA contrast agent offers a modality for improving tumor contrast in magnetic resonance imaging (MRI) of enhancing brain tumors. 3D gradient echo SL imaging has also shown potential to increase tissue characterization properties of MR imaging of human gliomas.
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PMID:3D spin-lock imaging of human gliomas. 1046 51


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