Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027627 (metastases)
 103,950 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Contrast-enhanced magnetic resonance imaging (MRI) of the liver and pancreas is frequently performed to improve the sensitivity and specificity of lesion detection in these organs. The concept of using tissue-specific contrast media is to selectively enhance the normal parenchyma, but not lesions, so that the contrast between tumorous and normal tissue is increased, and lesion detectability improved. Mangafodipir trisodium (MnDPDP) has been developed as a hepatocellular-specific contrast agent, but uptake has also been found in pancreatic tissue. In this study the safety and diagnostic efficacy of MnDPDP were investigated in both healthy volunteers and in patients with liver and pancreatic tumors. In healthy volunteers (n = 8), dose-dependent enhancement in T1-weighted images was observed in the normal liver and pancreatic parenchyma after infusion of MnDPDP at doses of 5 and 10 mumol/kg. The maximal enhancement in the two dose groups was 77 and 110% in the liver, and 57 and 84% in the pancreas, respectively. The enhancement-over-time profiles demonstrated that the effective imaging window was about 2 h for the liver, and over 4 h for the pancreas. There was no measurable enhancement in brain structures protected by intact blood-brain barrier, and no changes of clinical importance were found in vital signs or in blood and urinary chemistry variables. Compared with unenhanced images (including T2-weighted images), significantly more lesions were detected on MnDPDP-enhanced T1 images in 82 patients with liver tumors (mostly metastases). Features such as rim enhancement and the enhancement in hepatocellular carcinomas can provide information for differential diagnosis. In a study on patients with pancreatic tumors, mainly adenocarcinomas (n = 21) and islet cell tumors (n = 19), two additional lesions were found in the MnDPDP-enhanced images. The contrast enhancement in the pancreatic parenchyma can vary greatly, depending on the site of the enhancing part of the organ in relation to a large tumor. The tumors of both origins were also enhanced post-contrast, but to a lesser degree than the normal pancreatic tissue. MnDPDP enhancement was investigated in 30 liver metastases from endocrine tumors in 13 patients. These lesions showed a signal increase of about 49% post-contrast, which lasted longer than that in the normal liver tissue. The findings may help to distinguish these tumors from other metastatic tumors. T1-weighted sequences of four types, including a spin-echo and three variants of fast gradient-echo sequences, and various parameter combinations, were investigated in healthy volunteers (n = 6), with the aim of finding the optimal sequence for MnDPDP-enhanced MRI of the liver and pancreas. The fat-and-water out-of-phase, fast field (gradient)-echo sequence was the best for imaging of both the liver and pancreas. The studies have shown that MnDPDP is safe when given as an infusion, and is effective as a liver- and pancreas-specific contrast medium, with improved lesion detection in MRI of these organs. It is also useful for the characterization of liver tumors.
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PMID:Mangafodipir trisodium (MnDPDP)-enhanced magnetic resonance imaging of the liver and pancreas. 957 56

The aim of this study was to determine if different types of focal hepatic lesions can be differentiated by specific quantitative and qualitative imaging characteristics pre- and post-Mangafodipir trisodium (MnDPDP) administration using a computerized multivariable, discriminant analysis (DA). In a multicenter trial, 151 patients with focal liver disease were studied at 1.5 and 1.0 T using gradient-recalled echo T1 and fast spin-echo T2-weighted images pre and post MnDPDP (0.005 mmol/kg b.w.) i.v. administration. Analysis could be performed in 141 of 151 of the patients. The variables used in both single variable analysis and DA included contrast-to-noise ratios pre and post MnDPDP, presence of rim enhancement, margin, and heterogeneity of a lesion pre and post MnDPDP. The classification of diagnoses using DA was compared with a standard of reference (HCC in 23%, metastases in 25%, cyst in 13%, FNH in 10%, hemangioma in 11%, and other or no lesion in 18% of the patients; histology in 49%, long-term follow-up in 51% of the cases). In the differentiation of the various hepatic lesions, CNR together with the presence of heterogeneity or rim enhancement as variables for DA gave the highest sensitivity, specificity, and accuracy which ranged between 65 and 93, 44 and 83, and 65 and 86%, respectively. The DA models based on post-MnDPDP variables showed better classification results than the models based on pre-MnDPDP variables. An improvement of accuracy was observed when differentiating HCC from FNH lesion groups (48.9-67.4%; p < or = 0.05), and when differentiating HCC from metastasis lesion groups (68.3-84.1%; p < or = 0.01). In all regards there was no difference for T2-weighted images pre and post MnDPDP. By combining quantitative and qualitative variables, DA proved to be a useful tool in lesion discrimination. Due to considerable heterogeneity within some of the lesion type groups, the definite diagnostic impact of MnDPDP cannot be completely established yet, and further investigation is still necessary.
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PMID:MRI characteristics in focal hepatic disease before and after administration of MnDPDP: discriminant analysis as a diagnostic tool. 1186 75

Mangafodipir trisodium (MnDPDP) is a contrast agent for use in magnetic resonance imaging (MRI) of the liver. The agent is taken up by normal hepatocytes resulting in increased signal on T1-weighted imaging, and is excreted in the biliary system. Hepatocyte-containing liver neoplasms such as hepatomas or focal nodular hyperplasia (FNH), take up MnDPDP and demonstrate varying degrees of enhancement. Metastatic liver deposits and primary liver tumours of non-hepatocyte origin do not typically enhance with MnDPDP thus increasing their conspicuity compared with pre-contrast T1-weighted images. Metastases may demonstrate rim enhancement particularly on delayed imaging at 24 h, which can increase their conspicuity, thus allowing better visualization of small lesions. Functional biliary obstruction due to liver metastases can also result in wedge shaped areas of parenchymal enhancement. The MRI features of various focal liver after continuance with lesions following MnDPDP are discussed and illustrated including primary lesions such as hepatoma and secondary metastases.
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PMID:MnDPDP enhanced magnetic resonance imaging of focal liver lesions. 1247 27