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Ruby Del Risco Kollerud Hege S. Haugnes Bjørgulf Claussen Magne Thoresen Per Nafstad James M. Farnham Karl G. Blaasaas Øyvind Næss Lisa A. Cannon-Albright 《International journal of cancer. Journal international du cancer》2020,147(6):1604-1611
Similar family-based cancer and genealogy data from Norway and Utah allowed comparisons of the incidence of testicular cancer (TC), and exploration of the role of Scandinavian ancestry and family history of TC in TC risk. Our study utilizes data from the Utah Population Database and Norwegian Population Registers. All males born during 1951–2015 were followed for TC until the age of 29 years. A total of 1,974,287 and 832,836 males were born in Norway and Utah, respectively, of whom 2,686 individuals were diagnosed with TC in Norway and 531 in Utah. The incidence per year of TC in Norway (10.6) was twice that observed in Utah (5.1) for males born in the last period (1980–1984). The incidence rates of TC in Utah did not differ according to the presence or absence of Scandinavian ancestry (p = 0.669). Having a brother diagnosed with TC was a strong risk factor for TC among children born in Norway and Utah, with HR = 9.87 (95% CI 5.68–17.16) and 6.02 (95% CI 4.80–7.55), respectively; with even higher HR observed among the subset of children in Utah with Scandinavian ancestry (HR = 12.30, 95% CI 6.78–22.31). A clear difference in TC incidence among individuals born in Norway and descendants of Scandinavian people born in Utah was observed. These differences in TC rates point to the possibility of environmental influence. Family history of TC is a strong risk factor for developing TC in both populations. 相似文献
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Schraml C Clasen S Schwenzer NF Koenigsrainer I Herberts T Claussen CD Pereira PL 《Abdominal imaging》2008,33(6):643-651
Background To determine the accuracy of contrast-enhanced multislice computed tomography (CT) in the assessment of treatment success
immediately after CT-guided radiofrequency (RF) ablation.
Methods 26 patients with 38 Colorectal liver metastasis (CRM) were treated by CT-guided RF ablation. Pre-contrast and portal phase
CT features before and immediately after ablation were retrospectively evaluated quantitatively and qualitatively: Influence
of attenuation characteristics, safety margin, congruency between tumor and coagulation, and morphological criteria (shape,
margin distinction, margin configuration, and margin continuity) were investigated. Findings were statistically analyzed with
regard to local tumor progression.
Results Mean observation period for follow-up scans was 6.4 months (range: 3–40 months). Attenuation characteristics, safety margin,
and congruency had no significant effect on the probability of local tumor progression. Coagulations whose margin was categorized
as “discontinuous” were significantly more often associated with local recurrence (p = 0.038). No significant influence on local recurrence could be detected regarding coagulation shape, margin distinction,
and configuration.
Conclusion Computed tomography imaging immediately after RF ablation allows for morphological characterization of the coagulation and
provides a valid baseline status for follow-up imaging. However, in CRM, morphological image criteria and attenuation characteristics
have limited predictive value for immediate detection of persistent tumor. 相似文献
18.
Fritz Schick Hermann Einsele Renate Kost Stephan Duda Wulf-Ingo Jung Otto Lutz Claus D. Claussen 《Journal of magnetic resonance imaging : JMRI》1994,4(1):71-78
Magnetic resonance (MR) studies were performed in 14 patients as early as possible (21–110 days) after bone marrow transplantation (BMT). MR characteristics of lumbar vertebral bone marrow were studied with T1-weighted spin-echo imaging, water- and fatselective imaging with a frequency-selective excitation technique, and point-resolved spatially localized proton spectroscopy. Signals from water and fat protons and their T1 and T2 values were analyzed. Water proton signal intensity correlated well with cellularity within bone marrow, as determined with parallel iliac crest biopsies. The fraction of signal from water in red bone marrow of patients with allogeneic transplants from siblings (four cases) was significantly higher than in four patients with autologous transplants. The latter showed very low cellularity in the period of about 4 weeks after BMT because of the cytotoxic pretreatment of the bone marrow. The MR results in six patients with allogeneic transplants from unrelated donors ranged widely, depending on the complications after BMT. Analysis of data obtained with the different techniques showed that water- and fat-selective MR imaging and spectroscopic methods are useful for noninvasive monitoring of hematopoietic reconstitution after BMT. 相似文献
19.
Stauder NI Küttner A Schröder S Drosch T Beck T Stauder H Blumenstock G Claussen CD Kopp AF 《European radiology》2006,16(11):2512-2520
The objective of this study was to evaluate the accuracy of electrocardiography (ECG)-gated 16-slice multidetector-row computed
tomography (MDCT) in detection of stenosis of bypass grafts and native coronary arteries in patients who have undergone coronary
artery bypass grafting (CABG). ECG-gated contrast-enhanced MDCT using 12×0.75-mm collimation was performed in 20 patients
with recurrent angina 4.75 years after undergoing CABG. A total of 50 grafts, 16 arterial and 34 venous, were examined. All
graft and coronary segments were evaluated for stenosis in comparison with conventional coronary angiography (CCA). Among
the 80 arterial graft segments, 62 could be assessed (77.5%). Sensitivity, specificity, and positive and negative predictive
values for stenosis were 96.2%, 97.2%, 96.2%, and 97.2%, respectively. In a total of 180 venous graft segments, 167 could
be assessed. Sensitivity, specificity, and positive and negative predictive values for stenosis were 98.5%, 93.9%, 91.8%,
and 98.9%, respectively. MDCT could assess 179 of 260 native coronary artery segments (68.8%).Sensitivity, specificity, and
positive and negative predictive values for stenosis were 92.1%, 76.9%, 87.5%, and 84.7%, respectively. Sixteen-slice MDCT
provides excellent image quality and diagnostic accuracy in detection of graft and coronary artery lesions in patients with
suspected graft dysfunction. 相似文献
20.
Brodoefel H Klumpp B Reimann A Fenchel M Heuschmid M Miller S Schroeder S Claussen C Scheule AM Kopp AF 《European journal of radiology》2007,62(2):235-246
OBJECTIVE: The aim of this study was to assess the accuracy of MSCT in characterizing myocardial infarction (MI) and, thereby, determine the extent of early perfusion defect (ED), microvascular obstruction (MO) and transmural depth of late enhancement (LE) in comparison to MRI and histology. MATERIALS AND METHODS: Seven pigs were studied with MSCT (Somatom Sensation 64) and MRI (Magnetom Sonata) a median 1 and 21 days following temporary occlusion of a diagonal branch and creation of small reperfused infarction. For depiction of ED, CT images were acquired in the early arterial phase and following 35 s; LE and MO were evaluated on images obtained at 3, 5, 10 and 15 min. Thereby, a bolus/low-flow contrast injection protocol was used. Triphenyltetrazolium-chloride (TTC) stain and histology were obtained. Volumes of enhancement patterns were assessed as percentage of the ventricle and compared by Bland-Altman analysis. Segmental co-localization and graded transmurality was evaluated with weighted-kappa-test. RESULTS: Close spatial agreement was observed for MRI-MO and MSCT-MO (bias=0.55; CI=-1.49 to 2.60 at 5 min MSCT), TTC and MSCT-LE (bias=-1.28; CI=-3.76 to 1.19) or MRI-LE and MSCT-LE (bias=-0.79; CI=-4.19 to 2.60). There was good segmental co-localization for MO (weighted kappa=0.93) and high agreement for transmural extent of TTC, MRI-LE and MSCT-LE (weighted kappa=0.84 TTC versus MSCT; 0.86 MRI versus MSCT). Arterial and 35s ED significantly underestimated infarct size and showed poor segmental or transmural agreement (weighted kappa=0.33; 0.44). CONCLUSIONS: MSCT late-scans not only reliably depict size of MO and LE in acute or subacute infarct phases but, moreover, allow for accurate determination of LE transmurality. 相似文献