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OBJECTIVES To evaluate the value of the vascular index (VI) on Superb Microvascular Imaging (SMI; Canon Medical Systems Corporation, Tokyo, Japan) in comparison with grayscale ultrasound (US) alone for assessing breast masses. METHODS We evaluated a total of 70 breast masses (36 malignant and 34 benign lesions) in 70 consecutive patients using grayscale US and SMI. Two breast radiologists analyzed grayscale US alone and the combination of grayscale US and SMI. They also measured the VI based on SMI. The diagnostic performance of grayscale US alone and the combination of grayscale US and SMI was compared. The VI was compared between benign and malignant masses, and the optimal cutoff value was determined. In addition, the interobserver agreement in imaging analyses and the VI was assessed. RESULTS The interobserver agreements in imaging analyses and the VI were almost perfect. The VI of malignant breast masses was significantly higher than that of benign lesions (P

Purpose To evaluate the usefulness of magnetic resonance imaging (MRI) computer-aided detection and diagnosis (CAD) for the detection of tumor-infiltrating lymphocytes (TILs) in triple-negative breast cancer (TNBC) patients. TNBC is a heterogeneous malignancy with a varying prognosis. Recently, the importance of TILs in TNBC has been determined. Materials and Methods We retrospectively enrolled 60 lesions of TNBC. Either at 1.5T or 3T MRI, including T1, T2-weighted, and dynamic contrast-enhanced, images were obtained. The CAD results for all lesions were obtained, and we analyzed quantitative kinetic features including the initial peak enhancement and enhancement profiles. We divided the tumors into two groups: those with a TIL level of less than 50%, and those with a TIL level of 50% or more. Kinetic parameters were compared using Student's t-tests and chi-square tests. Results There were 48 low-TIL lesions and 12 high-TIL lesions. The portion of persistent enhancement of tumors was negatively associated with the TIL levels (P = 0.003). The persistent minus washout value of the low-TIL group was higher than that of the high-TIL group (P = 0.008). The odds ratios were 0.944 (P = 0.012) for the persistent portion and 0.971 (P = 0.008) for the persistent minus washout value. Conclusion The prediction model using kinetic enhancement parameters, particularly persistent proportion and plateau minus washout value, could be helpful for identifying TIL levels in TNBC and may be used as an imaging biomarker to guide the treatment plan. Level of Evidence: 4 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2017.

Purpose Nonlinear pre-reconstruction processing of the projection data in computed tomography (CT) where accurate recovery of the CT numbers is important for diagnosis is usually discouraged, for such a processing would violate the physics of image formation in CT. However, one can devise a pre-processing step to enhance detectability of lesions in digital breast tomosynthesis (DBT) where accurate recovery of the CT numbers is fundamentally impossible due to the incompleteness of the scanned data. Since the detection of lesions such as micro-calcifications and mass in breasts is the purpose of using DBT, it is justified that a technique producing higher detectability of lesions is a virtue. Methods A histogram modification technique was developed in the projection data domain. Histogram of raw projection data was first divided into two parts: One for the breast projection data and the other for background. Background pixel values were set to a single value that represents the boundary between breast and background. After that, both histogram parts were shifted by an appropriate amount of offset and the histogram-modified projection data was log-transformed. Filtered-backprojection (FBP) algorithm was used for image reconstruction of DBT. To evaluate performance of the proposed method, we computed the detectability index for the reconstructed images from clinically acquired data. Results Typical breast border enhancement artifacts were greatly suppressed and the detectability of calcifications and masses was increased by use of the proposed method. Compared to a global threshold-based post-reconstruction processing technique, the proposed method produced images of higher contrast without invoking additional image artifacts. Conclusions In this work, we report a novel pre-processing technique that improves detectability of lesions in DBT and has potential advantages over the global threshold-based post-reconstruction processing technique. The proposed method not only increased the lesion detectability but also reduced typical image artifacts pronounced in conventional FBP-based DBT. This article is protected by copyright. All rights reserved.

The purpose of this retrospective study was to evaluate whether tumor apparent diffusion coefficient (ADC) was correlated with pathologic biomarkers such as tumor cellularity, Ki67, tumor-infiltrating lymphocytes (TILs), and peritumoral lymphocytic infiltrate (PLI) in patients with estrogen receptor (ER)-positive breast cancer. The study was approved by the institutional review board and informed consent was waived. From July 2014 to December 2014, we reviewed 140 ER-positive tumors in 138 consecutive patients (range, 28–77 years; mean, 52 years) who underwent preoperative breast MRI and definitive surgery. All patients underwent diffusion-weighted imaging with a 3T scanner. Two radiologists drew the region of interest of the entire tumor and obtained the mean and pixel-based histogram of ADC. On pathology, two pathologists reviewed tumor cellularity, Ki67, TILs, and PLI. Multiple linear regression analysis was used to determine pathologic variables independently associated with ADC. Tumors with high tumor cellularity and high Ki67 had significantly lower ADCs than those with low tumor cellularity and low Ki67 (P < 0.05 for all). Tumors without PLI had significantly higher standard deviation than those with PLI (0.23 ± 0.08 versus 0.18 ± 0.05; P < 0.001). Median ADC was negatively correlated with tumor cellularity (r = −0.441), and Ki67 (r = −0.382). The standard deviation of ADC was also negatively correlated with the degree of PLI (r = −0.319). On multivariate linear regression analysis, tumor cellularity and Ki67 were independently associated with tumor ADC. Tumor ADC would be an MRI biomarker for the prediction of tumor aggressiveness indicators such as Ki67, tumor cellularity, and PLI in ER-positive breast cancer. Copyright © 2016 John Wiley & Sons, Ltd.

Purpose To qualitatively and quantitatively compare the diagnostic performance of rs-EPI (readout segmented echo planar imaging) and reduced FOV (field-of-view) EPI in patients with biopsy-proven breast cancer at 3T. Materials and Methods Between November 2013 and July 2014, 96 patients (age range, 30–75 years: mean, 52 years) with breast cancer were retrospectively enrolled in this study. In all patients, rs-EPI and rFOV EPI were performed using a 3T MR scanner. Differences between two sequences were compared quantitatively by measuring the tumor apparent diffusion coefficient (ADC), signal-to-noise ratio (SNR), contrast, and contrast-to-noise ratio (CNR). Two independent readers visually assessed overall image quality, lesion conspicuity, and reader preference. The regions of interest (ROIs) were drawn in the whole tumor and in the normal breast parenchyma. Comparisons of quantitative and qualitative parameters between two sequences were performed using the Mann–Whitney and the paired t-test. Results SNR was significantly higher in rFOV EPI than in rs-EPI (51.88 ± 27.68 vs. 76.46 ± 50.20, P < 0.001). Mean tumor ADC value and normal tissue ADC were significantly lower in rFOV EPI (P < 0.001). Absolute tumor mean and minimum ADCs of rFOV EPI were significantly lower than those of rs-EPI (P < 0.001 for both). However, normalized ADC did not show a significant difference between the two sequences (P = 0.737). Lesion conspicuity and overall image quality of rFOV EPI were significantly higher than those of rs-EPI for both readers (P = 0.025 and < 0.001). Conclusion In breast cancer, rFOV EPI provided significantly higher image quality, lesion conspicuity, and SNR than rs-EPI. J. MAGN. RESON. IMAGING 2015;42:1679–1688.

Objectives The purpose of our study was to compare the accuracy of detection of lesions in the coronal and transverse views on automated breast sonography. Methods Three breast radiologists independently interpreted automated breast sonograms from 113 women: 14 with negative findings and 99 with known breast lesions (99 benign and 53 malignant findings). The readers were asked to detect the presence or absence of the abnormalities using the transverse and coronal views in different reading sessions. If a lesion was detected, we evaluated its location, sonographic features, including shape, orientation, margin, boundary type, and echo pattern, and final American College of Radiology Breast Imaging Reporting and Data System assessment category. The reading time was also evaluated. Results Of 456 potential detections (152 lesions with 3 readers), 80.5% of the detections were made with the transverse view, and 67.3% were made with the coronal view. The detection rates for both malignant and benign lesions were significantly higher for the transverse view than for the coronal view (P < .001). The reading time for the coronal view was less than that for the transverse view (mean ± SD, 3.83 ± 1.71 versus 5.57 ± 2.21 minutes). The intraclass correlation coefficient values for lesion location, distance from the nipple, and lesion size for both views all exceeded 0.7. Conclusions Although the coronal view on automated breast sonography showed comparable reliability and a shorter reading time, the detection rate for the coronal view was significantly lower than that for the transverse view in both benign and malignant lesions. It is preferable to reserve the coronal view as an additional method to the transverse view.

OBJECTIVES The purpose of this study was to evaluate the use and performance of supplemental screening whole-breast sonography in conjunction with mammography in asymptomatic women with dense breast tissue. METHODS A total of 28,796 asymptomatic women underwent screening mammography. Among 20,864 women with dense breasts (72%), 8359 underwent additional sonography as part of their screening examinations. We classified women with mammographically dense breasts into mammography-only and mammography-plus-sonography groups. The reference standard was a combination of pathologic results and clinical follow-up at 2 years. We compared the recall rate, cancer detection yield, sensitivity, specificity, and positive predictive value in each group. RESULTS Among the 20,864 women with dense breasts, 35 cancers were diagnosed, with a mean size of 13 mm. The cancer detection yield was 0.480 per 1000 women in the mammography-only group and increased to 2.871 in the mammography-plus-sonography group. Of 24 cancers detected in the mammography-plus-sonography group, the mean size was 11 mm, and the axillary lymph nodes were negative in 19 of 20. The sensitivity was significantly higher in the mammography-plus-sonography group than the mammography-only group (100% versus 54.55%; P = .002). The positive predictive values of sonographically prompted biopsy were 11.1% for the mammography-plus-sonography group and 50% for the mammography-only group. CONCLUSIONS Supplemental screening whole-breast sonography increases the cancer detection yield by 2.391 cancers per 1000 women with dense breast tissue over that of mammography alone. It is beneficial for increased detection of breast cancers that are predominantly small and node negative; however, it also raises the number of false-positive results.