Enhanced mass on contrast-enhanced breast MR imaging: Lesion characterization using combination of dynamic contrast-enhanced and diffusion-weighted MR images
ABSTRACT To evaluate the diagnostic accuracy of a combination of dynamic contrast-enhanced MR imaging (DCE-MRI) and diffusion-weighted MR imaging (DWI) in characterization of enhanced mass on breast MR imaging and to find the strongest discriminators between carcinoma and benignancy.
We analyzed consecutive breast MR images in 270 patients; however, 13 lesions in 93 patients were excluded based on our criteria. We analyzed tumor size, shape, margin, internal mass enhancement, kinetic curve pattern, and apparent diffusion coefficient (ADC) values. We applied univariate and multivariate analyses to find the strongest indicators of malignancy and calculate a predictive probability for malignancy. We added the corresponding categories to these prediction probabilities for malignancy and calculated diagnostic accuracy when we consider category 4b, 4c, and 5 lesions as malignant and category 4a, 3, and 2 lesions as benign. In a validation study, 75 enhancing lesions in 71 patients were examined consecutively.
Irregular margin, heterogeneous internal enhancement, rim enhancement, plateau time-intensity curve (TIC) pattern, and washout TIC pattern were the strongest indicators of malignancy as well as past studies, and ADC values less than 1.1x10(-3) mm2/s were also the strongest indicators of malignancy. In a validation study, sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 92% (56/61), 86% (12/14), 97% (56/58), 71% (12/17), and 91% (68/75), respectively.
The combination of DWI and DCE-MRI could produce high diagnostic accuracy in the characterization of enhanced mass on breast MR imaging.
- SourceAvailable from: Ahmet Veysel Polat
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- "Preliminary data of DWI studies of the breast showed high sensitivity for detecting cancer, based on low diffusivity in carcinomas due to higher cell density (Park et al., 2007; Yoshikawa et al., 2008). Furthermore, quantitative DWI analyses have shown that the apparent diffusion coefficient (ADC) is significantly lower in many breast carcinomas compared with benign lesions, is supporting as a potential diagnostic tool (Guo et al., 2002; Kinoshita et al., 2002; Sinha et al., 2002; Wenkel et al ., 2002; Woodhams et al., 2005; Rubesova et al., 2006; Park et al., 2007; Hatakenaka et al., 2008; Peters et al., 2008; Yabuuchi et al., 2008; Yoshikawa et al., 2008; Lo et al., 2009; Partridge et al., 2010; Kul et al., 2011; Sonmez et al., 2011). "
ABSTRACT: The role of magnetic resonance diffusion-weighted imaging (DWI) to differentiate between malignant and benign lesions in the breast using mean apparent diffusion coefficient (ADC) values was evaluated prospectively in this study. Fifty female patients with 61 histopathologically proven solid breast lesions underwent dynamic contrast-enhanced magnetic resonance imaging and DWI using the spin-echo echo-planar technique. ADC maps have been obtained and ADCs of the lesions were calculated without knowledge of histopathological diagnosis. Golden standard was histology to define benign and malignant lesions. Statistical analysis was used to compare ADC values in the benign and malignant group and to calculate best cut-off value for distinguishing both groups based on receiver operator-curve characteristics (ROC). Differentiation of the benign and the malignant masses revealed that the threshold value of the ADC in maximum sensitivity and specificity was 1.22×10-3 mm2/s; at this threshold sensitivity was 96.2%, its specificity was 88.5%, and its positive predictive value was 86.2%. Its negative predictive value was 96.9%, and the accuracy rate was 91.8%. ROC analysis showed an area under the curve of 0.924 (p<0.001). Breast MRI with DWI using ADC measurements can be useful in the differentiation of benign and malignant breast lesions.Journal of Experimental and Clinical Medicine 01/2013; 30(4):305-310. DOI:10.5835/jecm.omu.30.04.005
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- "The ability of DCE-and DW-MRI to provide a spatial depiction of these anatomical and physiological conditions within a tumor makes them natural tools for probing tumor heterogeneity. The reporting of MRI has long relied on visual assessment of several scans having different contrasts, but in relation to breast cancer, few studies have exploited this inherently multiparametric data in a unified manner   . Moreover, the most recent works mainly address the problem of comparing and retrospectively integrating the contributions from the different modalities, without exploiting the conjunct information. "
ABSTRACT: In order to better predict and follow treatment responses in cancer patients, there is growing interest in noninvasively characterizing tumor heterogeneity based on MR images possessing different contrast and quantitative information. This requires mechanisms for integrating such data and reducing the data dimensionality to levels amenable to interpretation by human readers. Here we propose a two-step pipeline for integrating diffusion and perfusion MRI that we demonstrate in the quantification of breast lesion heterogeneity. First, the images acquired with the two modalities are aligned using an intermodal registration. Dissimilarity-based clustering is then performed exploiting the information coming from both modalities. To this end an ad hoc distance metric is developed and tested for tuning the weighting for the two modalities. The distributions of the diffusion parameter values in subregions identified by the algorithm are extracted and compared through nonparametric testing for posterior evaluation of the tissue heterogeneity. Results show that the joint exploitation of the information brought by DCE and DWI leads to consistent results accounting for both perfusion and microstructural information yielding a greater refinement of the segmentation than the separate processing of the two modalities, consistent with that drawn manually by a radiologist with access to the same data.International Journal of Biomedical Imaging 11/2012; 2012:676808. DOI:10.1155/2012/676808
Conference Paper: Simple techniques for storing ultraclean electron tube components[Show abstract] [Hide abstract]
ABSTRACT: Recent advances in cleaning techniques for electron device components, coupled with simple techniques for the detection of monolayer amounts of contaminants, have enabled routine achievement of radically improved standards of cleanliness for electron device parts and assemblies. A major practical limitation has been the inability to store clean parts for extended periods without significant degradation of this high order of cleanliness. This paper describes the development of simple storage techniques capable of keeping parts free of detectable contaminants for periods up to several months. Some of the important factors in design of suitable storage containers, their cleanliness requirements, and suitable storage atmospheres are considered.Electron Devices Meeting, 1957 International; 02/1957