ORIGINAL ARTICLE PURPOSE We aimed to determine the apparent diffusion coefficients (ADCs) of focal breast lesions on diffusion-weighted magnetic resonance imaging (DW-MRI) and to evaluate whether ADC measurement can be used to characterize lesions as benign or malignant.
MATERIALS AND METHODSFifty-one patients between the ages of 18-79 years (mean age, 48.5 years) with 51 histopathologically verified breast lesions were included in this study. The patients were examined with a 1.5 Tesla system using a bilateral phased-array breast coil. Spin-echo echo-planar imaging was used. The images were obtained with b values of 50, 400, and 800 s/ mm 2 . The ADC values were calculated for breast lesions and for normal fibroglandular tissue. Receiver operating characteristics analyses were performed to find the threshold ADC values. /s (sensitivity, 88.5%; specificity, 100%). With the ADC ratio (lesion to normal fibroglandular tissue), the threshold was 0.8 (sensitivity, 91.4%; specificity, 100%). The ADC value obtained from malignant lesions was statistically different from that of benign lesions (P < 0.001). CONCLUSION Diffusion-weighted imaging can be used to differentiate malignant and benign breast lesions.
RESULTS
Breast cancer is one of the leading causes of death from cancer in women (1). The use of magnetic resonance imaging (MRI) has a relatively short history for the diagnosis of breast lesions. Breast MRI-as a different diagnostic tool from mammography and ultrasonography (US)-can show tissue perfusion characteristics of the masses on breast parenchyma, as well as morphologic features, such as the contour, size, and shape of the breast lesions. Although conventional MRI sequences have an important role in the differential diagnosis of breast masses, this technology has a low specificity, thus requires the support of additional imaging techniques (2-4). Diffusion-weighted MRI (DW-MRI) is an active field of research in MRI. In addition to diffusion-weighted imaging (DWI), apparent diffusion coefficient (ADC) maps can be created, and quantitative measurements can be performed. Recent studies have shown a high accuracy rate in the differentiation between malignant and benign breast lesions using DW-MRI and ADC measurements (5-7). The measured ADC values were significantly lower in malignant lesions compared with benign lesions. Malignant breast tumors show a high amount of cellular structure (due to the intensity of the tumor tissue), resulting in low ADC values for these lesions (5-7).The aim of this study was to evaluate the value of DWI and ADC values in the differential diagnosis of benign and malignant breast lesions.
Materials and methods
Patient selectionPatients with a suspicious mass diagnosed with mammography or US that were considered for a biopsy procedure were included in this prospective study.The local ethics committee approved the study, and informed written consent was obtained from each patient.Seventy patients who had a suspicious lesion on mammography or US according to Breast Imaging-Reporting a...