Diffusion-Weighted Magnetic Resonance Imaging in Suspicious Breast Lesions Detected on Ultrasonography and Mammography With Pathological Correlation

Introduction Diffusion-weighted magnetic resonance imaging (DW-MRI), an advanced functional imaging method, offers a notable advantage over traditional dynamic contrast-enhanced MRI (DCE-MRI) by generating tissue contrast without requiring the injection of intravenous contrast agents. The aim of the study is to evaluate the role of DW-MRI in suspicious breast lesions encountered primarily on ultrasonographic and mammographic evaluation. Methods A hospital-based cross-sectional study was performed between July 2023 and December 2023, including 34 suspicious breast lesions in 32 females detected on ultrasonography and mammography. Cases underwent MRI on a 1.5 Tesla scanner using a dedicated breast coil. DW MRI was done with b-values of 500, 800, and 1000 s/mm². Lesions were characterized by ultrasonography and mammography as per the ACR BI-RADS lexicon. Histopathological diagnosis was considered the gold standard of reference. Results Of 34 breast lesions, 16 (47.1%) were benign and 18 (52.9%) were malignant. The cut-off ADC value derived by the receiver operating characteristic (ROC) curve was 1.12 x10-3 mm²/s using different b values of 500, 800, and 1000 s/mm², which yielded optimal sensitivity (88.6%) and specificity (78.6%). The mean apparent diffusion coefficient (ADC) values of benign and malignant lesions were 1.51±0.22 x10-3 mm²/s and 1.0±0.09x10-3 mm²/s, respectively (p<0.0001). The mean ADC value of normal breast parenchyma was 1.68 ± 0.02 x 10-3 mm²/s (p<0.0001). DW‑MRI achieved a sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of DW-MRI by using ADC mapping that were found to be 88.6%, 78.6%, 83.8%, 84.6%, and 84.1%, respectively, in this study. Conclusion DW-MRI can be a potential adjunct to routine screening and diagnostic modalities and can be used as a problem-solving tool in suspicious breast lesions encountered on conventional imaging.