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)

MR images can be acquired with high spectral and spatial resolution to precisely measure lineshapes of the water and fat resonances in each image voxel. Previous work suggests that the high-resolution spectral information can be used to improve image contrast, SNR, sensitivity to contrast agents and to physiologic and biochemical processes that affect local magnetic susceptibility gradients. The potential advantages of high-resolution spectroscopic imaging (SI) suggest that it might be useful for early detection and characterization of tumors. The present experiments evaluate the use of high-resolution SI to discriminate between metastatic and nonmetastatic rodent Dunning prostate tumors. SI datasets were obtained at 4.7 Tesla with an in-plane resolution of 350-500 micron in a single 1.0-mm slice, and 6-8 Hz spectral resolution, before and after i.v. injection of an iron oxide contrast agent. Images of water signal peak height in nonmetastatic tumors were smoother in the tumor interior than images of metastatic tumors (P <.004 by t-test) before contrast media injection. This difference was stronger in contrast-enhanced images (P <.0004). In addition, the boundary between the tumor and muscle was more clearly demarcated in nonmetastatic than metastatic tumors. Combinations of image texture, tumor edge morphology, and changes in T2* following contrast media injection improved discrimination between metastatic and nonmetastatic tumors. The data presented here do not demonstrate that effective discrimination between metastatic and nonmetastatic tumors depends on the use of high-resolution SI. However, the results suggest that SI and/or other MR methods that provide similar contrast might be used clinically for early and accurate detection of metastatic disease.
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PMID:Differentiation of nonmetastatic and metastatic rodent prostate tumors with high spectral and spatial resolution MRI. 1137 83

Experimental data show accumulation of superparamagnetic iron oxide (SPIO) particles in atherosclerotic plaques. SPIO uptake occurred in plaques, suggesting an increased endothelial permeability and macrophage infiltrates as signs of inflammatory plaque activity. We incidentally observed SPIO uptake in aortic and arterial wall segments in patients who had originally received the magnetic resonance (MR) contrast agent for staging lymph node metastases. Twenty patients (19 male, 1 female; mean age, 64; range, 41-78 years) with bladder or prostate cancer underwent MR imaging (MRI) using a T2*-weighted high-resolution gradient-echo sequence prior to and 24-36 hours after intravenous injection of 2.6 mg of Fe/kg of SPIO (Sinerem). The aorta, both common external and internal iliac, as well as both superficial femoral arteries, were retrospectively analyzed for atherosclerotic wall changes. One patient was excluded. A positive finding was defined as an area of pronounced signal loss on postcontrast images clearly confined to the arterial wall, which was absent in the precontrast examination or increased in size. Such a finding was observed in one to three arteries in 7 of the 19 patients. The pronounced signal loss in the wall of the aorta and pelvic arteries seen in part of an elderly patient population after intravenous SPIO administration strongly suggests that this contrast agent accumulates in human atherosclerotic plaques.
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PMID:Magnetic resonance imaging of atherosclerotic plaques using superparamagnetic iron oxide particles. 1159 58

Antiangiogenic therapy is a promising new strategy of inhibiting tumor growthand formation of metastases. Recently, a number of compounds with different effects on tumor endothelial cells have entered clinical trials and revealed the need for diagnostic methods to detect their biological activity. Dynamic enhanced magnetic resonance imaging (dyMRI) is used in most clinical trials with antiangiogenic active compounds. We evaluated this method by using PTK787/ZK 222584, a specific inhibitor of the VEGF-receptor tyrosine kinases, which showed antitumoral and antiangiogenic activity in a murine renal cell carcinoma (RENCA) model. After intrarenal application of RENCA cells, mice developed a primary tumor and metastases to the lung and abdominal lymph nodes. After daily oral therapy for 21 days with either PTK787/ZK 222584 at a dose of 50 mg/kg or vehicle, primary tumors of all animals were analyzed by dyMRI. Gadolinium-DOTA (Dotarem) was used as a contrast agent to detect vessel permeability and contrast agent extravasation, whereas intravascular iron oxide nanoparticles (Endorem) were used to detect partial tumor blood volume. Additionally, vessel density, architecture, diameter, and blood flow velocity were investigated by appropriate methods. Surprisingly, no changes in extravasation occurred under treatment with PTK787/ZK 222584 as compared with the control group, whereas a significant decrease in vessel permeability occurred. Furthermore, an increase in partial blood volume was found in the PTK787/ZK 222584-treated group, although vessel density was reduced as seen by histology. Using the corrosion cast technique, reduction in vessel density was significant but not very pronounced and predominantly attributable to the loss of microvessels only. This finding correlated with a shift to large vessel diameters in the primary tumors of PTK787/ZK 222584-treated animals and with reduction of blood flow velocity in the tumor feeding renal artery. From these findings, we conclude that the treatment with PTK787/ZK 222584 primarily reduces the number of tumor microvessels, accompanied by a hemodynamic dilation of the remaining vessels. This dilation could influence the result of dyMRI such that no change in extravasation or even an increase in partial tumor blood volume could be observed.
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PMID:PTK787/ZK 222584, a specific vascular endothelial growth factor-receptor tyrosine kinase inhibitor, affects the anatomy of the tumor vascular bed and the functional vascular properties as detected by dynamic enhanced magnetic resonance imaging. 1212 35

The current classification system of renal tumors is based on morphologic criteria, as supported by genetic findings. We present a group of previously unclassified tumors with similar morphologic and genetic features, suggesting a new entity within renal neoplasms. Seven renal tumors from five patients (ages 31-67 years) were analyzed. All cases were stained with periodic acid-Schiff, Hale's colloidal iron (HCI), and Alcian blue (AB) at pH 2.5/1.0 with and without hyaluronidase (HA) digestion. Immunohistochemical (IHC) stains were performed for CK8, CK18, CK19, vimentin, villin, Tamm-Horsfall protein (THP), renal cell carcinoma marker (RCC), epithelial membrane antigen (EMA), ulex europaeus agglutinin (UEA-1), soy bean agglutinin (SBA), peanut agglutinin (PNA), and MIB-1. Comparative genomic hybridization (CGH) and loss of heterozygosity (LOH) studies were performed on all cases. All tumors showed circumscribed growth, a tubular growth pattern with focal solid areas, no significant nuclear atypia and absence of necrosis, desmoplasia, or inflammation. Abundant extracellular mucin was present. Immunohistochemistry stains support collecting duct origin (EMA+, PNA+, SBA+/-, CK 8/18/19+, vimentin+/-, UEA-1-, RCC-, villin-, THP-). The proliferative rate was low (<1%). CGH showed multiple consistent chromosomal losses (-1,-4, -6, -8, -9, -13, -14, -15, -22). Clinical outcome was favorable, with recurrences but no known distant metastases or death of disease. These findings are distinct from all previously classified renal neoplasms. Our data suggest the presence of a unique tumor entity within tumors of probable collecting duct origin: tubular-mucinous renal tumors of low malignant potential.
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PMID:Low-grade tubular-mucinous renal neoplasms: morphologic, immunohistochemical, and genetic features. 1242 95

The aim of this study was to compare the diagnostic efficacy of superparamagnetic iron oxide (SPIO)-enhanced MRI for the detection and diagnostic accuracy of focal liver lesions with helical contrast enhanced CT (CECT) and CT during arterial portography (CTAP). Thirty-nine patients (25 men and 14 women, mean age 63.5 years) were examined by SPIO-MRI and triple-phase CECT. Eleven of them were also examined by CTAP. There were a total of 96 confirmed focal hepatic lesions, 61 metastatic cancers in 18 patients and 35 hepatocellular carcinomas (HCCs) in 21 patients. Final diagnosis was established by operation in 25 cases, by biopsy in 7 cases, and by progression of disease on follow-up examination in the other 7 cases. The sensitivity of SPIO-MRI for HCC detection was almost equal to CECT, but that of SPIO-MRI for metastatic cancer detection, especially cancers smaller than 1 cm in size, was significantly superior to CECT. The sensitivity of SPIO-MRI for both HCC and metastatic cancer detection was almost equal to that of CTAP, but the specificity of SPIO-MRI for detection of both lesions was significantly superior to that of CTAP because CTAP produced a higher incidence of false-positive findings. In conclusion, SPIO-MRI could take the place of CTAP as a non-invasive excellent modality to determine the distribution of hepatic lesions preoperatively. SPIO-MRI could also be a useful modality to follow liver metastasis postoperatively in patients with advanced digestive cancers.
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PMID:[Evaluation of the diagnostic efficacy of SPIO enhanced MRI in patients with focal hepatic lesions--comparison with CECT and CTAP]. 1248 62

A 51-year-old male presented with a 5 cm left knee mass. Fine needle aspiration revealed large epithelioid cells with prominent nucleoli and abundant cytoplasmic pigment, consistent with malignant melanoma. Left inguinal lymphadenopathy was present, which was suspicious for metastatic disease by ultrasound examination. A dark perianal skin lesion was also identified, therefore raising the possibility of a primary melanoma. The knee and perianal lesions were resected and inguinal sentinel node biopsy was performed. In the specimen from the knee, there were clusters and fascicles of spindle and epithelioid cells with prominent nucleoli. Many of the cells displayed abundant, granular, brown, cytoplasmic pigment. The lymph node showed clusters of similar cells located in the subcapsular sinus. Immunohistochemical study showed that the cells expressed CD68, but failed to express S-100, MART-1, and gp100. The cytoplasmic pigment was positive for iron staining. The final diagnosis was pigmented villonodular synovitis. This case illustrates that pigmented villonodular synovitis may present with lymphadenopathy, mimicking a malignant process, including melanoma. Immunohistochemical studies may be essential for establishing the correct diagnosis.
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PMID:Extensive pigmented villonodular synovitis with markedly pigmented lymphadenopathy and its implication for differential diagnosis with malignant melanoma. 1271 34

BACKGROUND: The molecular mechanisms by which iron is physiologically transported trough the cellular membranes are still only partially understood. Several studies indicate that a reduction step of ferric iron to ferrous is necessary, both in the case of transferrin-mediated and transferrin-independent iron uptake. Recent studies from our laboratory described gamma-glutamyltransferase activity (GGT) as a factor capable to effect iron reduction in the cell microenvironment. GGT is located on the outer aspect of plasma membrane of most cell types, and is often expressed at high levels in malignant tumors and their metastases. The present study was aimed at verifying the possibility that GGT-mediated iron reduction may participate in the process of cellular iron uptake. RESULTS: Four distinct human tumor cell lines, exhibiting different levels of GGT activity, were studied. The uptake of transferrin-bound iron was investigated by using 55Fe-loaded transferrin, as well as by monitoring fluorimetrically the intracellular iron levels in calcein-preloaded cells. Transferrin-independent iron uptake was investigated using 55Fe complexed by nitrilotriacetic acid (55Fe-NTA complex).The stimulation of GGT activity, by administration to cells of the substrates glutathione and glycyl-glycine, was generally reflected in a facilitation of transferrin-bound iron uptake. The extent of such facilitation was correlated with the intrinsic levels of the enzyme present in each cell line. Accordingly, inhibition of GGT activity by means of two independent inhibitors, acivicin and serine/boric acid complex, resulted in a decreased uptake of transferrin-bound iron. With Fe-NTA complex, the inhibitory effect - but not the stimulatory one - was also observed. CONCLUSION: It is concluded that membrane GGT can represent a facilitating factor in iron uptake by GGT-expressing cancer cells, thus providing them with a selective growth advantage over clones that do not possess the enzyme.
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PMID:Possible role of membrane gamma-glutamyltransferase activity in the facilitation of transferrin-dependent and -independent iron uptake by cancer cells. 1279 6

The effect of hyperthermia on cervical lymph node metastasis of VX7 tongue cancer in female Japanese white rabbits was investigated. Magnetoliposomes (MLs) with a neutral surface charge and a size of 94.1 nm were used as heating mediators. MLs were injected into the tongue 20 days after tumor transplantation, and we examined whether they reached the metastatic deep cervical lymph node. The highest magnetite concentration 24 h after ML injection was detected in the lymph node, followed by tongue, spleen, blood, and liver. Rabbits were separated into three groups: group I as the control; group II with ML injection alone; and group III with ML injection and hyperthermia 24 h after ML injection, generated by applying an alternating magnetic field (118 kHz, 384 Oe) to the neck region. The hyperthermic effect was evaluated in terms of the percentage of necrosis in proportion to the metastatic tumor and the apoptotic index (AI), defined as the ratio of TUNEL-positive cells. The temperature of lymph nodes in group III reached over 44 degrees C. The mean area of necrosis in group III was 58.0%, which was significantly higher than that in group I (19.6%) or group II (20.4%). The AI in group III was 22.9%, significantly higher than in group I (1.67%) or II (1.42%). The difference between group I and II was not statistically significant. Group III tumor sites around MLs showed necrosis or apoptosis-positive cells induced by hyperthermia. These results indicate that MLs injected into the tongue can target cervical lymph node metastases and accumulate there at concentrations sufficient to generate therapeutically effective temperatures.
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PMID:Selective hyperthermia using magnetoliposomes to target cervical lymph node metastasis in a rabbit tongue tumor model. 1296 84

In imaging diagnosis of metastatic liver neoplasms, particularly in preoperative evaluation, it is necessary to detect all lesions, note involved hepatic segments, determine relations with intrahepatic vascular structure, evaluate local invasiveness of lesions, and exclude the presence of extrahepatic metastases. Various imaging features can be demonstrated with appropriate imaging techniques and provide useful information for differential diagnosis or determination of the primary site. Multip lemodalities such as ultrasonography, computed tomography (CT), magnetic resonance imaging (MRI), and angiography including CT during arterial portography and CT during hepatic arteriography are used for the diagnosis of metastatic liver neoplasms, and it is important to know the characteristics of each. Among the advances in imaging technology, the practical use of super-paramagnetic iron oxide-enhanced MRI (SPIO-enhanced MRI) has had a major impact. SPIO-enhanced MRI is a promising imaging modality for the detection of metastatic liver neoplasms because of its relatively high sensitivity and extremely high specificity. Accumulation of additional results is still necessary, but the imaging strategy for metastatic liver neoplasms will likely be based mainly on SPIO-enhanced MRI in the future.
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PMID:[Image evaluation of liver metastases]. 1457 54

The therapy of gastrointestinal tumors is becoming more and more sophisticated and complex. This is due to an improved understanding of the pathogenesis of tumors, a more detailed classification and increasing therapeutic options. The basis of optimized therapeutic concepts is the exact evaluation of tumor spread and exact staging. The following review describes some of the most recent staging concepts in gastrointestinal tumors. Multislice computed tomography (CT), positron emission tomography (PET) and new supraparamagnetic iron oxide contrast agents for magnetic resonance imaging enable an increasing quality of the visualization of tumors and metastases. 3D imaging will be used for planning of surgical interventions in the future. Optical coherence tomography may contribute to an improved tumor staging and, thus, to the safety of limited interventions in early oesophageal- and gastric cancer patients. Laparoscopy and laparoscopic ultrasound become increasingly important for the identification of small metastases in the peritoneum, in lymph nodes and in the liver. The sentinel lymph node concept will contribute to an improved staging and individualized therapy as well.
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PMID:New concepts of staging in gastrointestinal tumors as a basis of diagnosis and multimodal therapy. 1500 45


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