Diffusion-weighted Imaging Improves the Diagnostic Accuracy of Conventional 3.0-T Breast MR Imaging

Abstract

Purpose:To evaluate the incremental value of diffusion-weighted (DW) imaging and apparent diffusion coeffi cient (ADC) mapping in relation to conventional breast magnetic resonance (MR) imaging in the characterization of benign versus malignant breast lesions at 3.0 T. Materials and Methods:This retrospective HIPAA-compliant study was approved by the institutional review board, with the requirement for informed patient consent waived. Of 550 consecutive patients who underwent bilateral breast MR imaging over a 10-month period, 93 women with 101 lesions met the following study inclusion criteria: They had undergone three-dimensional (3D) high -spatial-resolution T1-weighted contrast material-enhanced MR imaging, dynamic contrastenhanced MR imaging, and DW imaging examinations at 3.0 T and either had received a pathologic analysis-proven diagnosis (96 lesions) or had lesion stability confi rmed at more than 2 years of follow-up (fi ve lesions). DW images were acquired with b values of 0 and 600 sec/mm 2 . Regions of interest were drawn on ADC maps of breast lesions and normal glandular tissue. Morphologic features (margin, enhancement pattern), dynamic contrastenhanced MR results (semiquantitative kinetic curve data), absolute ADCs, and glandular tissue-normalized ADCs were included in multivariate models to predict a diagnosis of benign versus malignant lesion. Results:Forty-one (44%) of the 93 patients were premenopausal, and 52 (56%) were postmenopausal. Thirty-three (32.7%) of the 101 lesions were benign, and 68 (67.3%) were malignant. Normalized ADCs were signifi cantly different between the benign (mean ADC, 1.1 3 10 2 3 mm 2 /sec 6 0.4 [standard deviation]) and malignant (mean ADC, 0.55 3 10 2 3 mm 2 /sec 6 0.16) lesions ( P , .001). Adding normalized ADCs to the 3D T1-weighted and dynamic contrast-enhanced MR data improved the diagnostic performance of MR imaging: The area under the receiver operating characteristic curve improved from 0 .89 to 0.98, and the false-positive rate decreased from 36% (nine of 25 lesions) to 24% (six of 25 lesions). Conclusion:DW imaging with glandular tissue-normalized ADC assessment improves the characterization of breast lesions beyond the characterization achieved with conventional 3D T1-weighted and dynamic contrast-enhanced MR imaging at 3.0 T.q RSNA, 2010

MRI in the differential diagnosis of primary architectural distortion detected by mammography

“…entiation of benign and malignant breast lesions and may increase the accuracy of conventional breast MRI assessment (17,19). Ei Khouli et al (17) showed that ADC values significantly improved the ability of DCE-MRI to discriminate between benign and malignant lesions.…”

“…Ei Khouli et al (17) showed that ADC values significantly improved the ability of DCE-MRI to discriminate between benign and malignant lesions. Yabuuchi et al (21,22) concluded that the application of DWI together with DCE-MRI contributes to an improved diagnostic accuracy of breast MRI.…”

“…One possible solution to improve this is to use apparent diffusion coefficient (ADC) values derived from diffusion-weighted imaging (DWI) to characterize breast tumors, and promising results have been reported by studies that combined ADC values and DCE-MRI in data analysis (17)(18)(19)(20)(21)(22). Nevertheless, few investigations have specifically evaluated MRI findings of AD detected by mammography, and moreover, the standard MRI scanning techniques have evolved since publication of these studies (23,24).…”

Diffusion weighted MRI for detecting and monitoring cancer: a review of current applications in body imaging

“…The normalization is thought to overcome factors that affect ADC values, including ADC variations across the menstrual cycle (as reported previously by Partridge et al [49]) and variations of scanning parameters. The normalized ADC value with a cut-off point of 0.7 significantly improved the diagnostic performance of DWI in discriminating benign from malignant lesions (48).…”

“…Another attempt to improve the diagnostic performance of diffusion-weighted MRI in breast MRI was embodied in the suggestion of El Khouli et al (48) to normalize the ADC value of breast lesions to the ADC value of the ipsilateral remote glandular tissue (Fig. 3).…”