Separation of benign and malignant breast lesions using dynamic contrast enhanced MRI in a biopsy cohort.

Purpose: To assess the diagnostic utility of contrast kinetic analysis for breast lesions and background parenchyma of women undergoing MRI-guided biopsies, for whom standard clinical analysis had failed to separate benign and malignant lesions.
Materials and Methods: This study included 115 women who had indeterminate lesions based on routine diagnostic breast MRI exams and underwent an MRI (3 Tesla) -guided biopsy of one or more lesions suspicious for breast cancer. Breast dynamic contrast-enhanced (DCE)-MRI was performed using a radial stack-of-stars three-dimensional spoiled gradient echo pulse sequence and modified k-space weighted image contrast image reconstruction. Contrast kinetic model analysis was conducted to characterize the contrast enhancement patterns measured in lesions and background parenchyma (BP). The transfer rate (K ^trans ), interstitial volume fraction (v _e ), and vascular volume fraction (v _p ) estimated from the lesion and BP were used to separate malignant from benign lesions.
Results: The patients with malignant lesions had significantly (P < 0.05) higher median lesion-K ^trans (0.081 min ^-1 ), higher median BP-K ^trans (0.032 min ^-1 ), and BP-v _p (0.020) than those without malignant lesions (0.056 min ^-1 , 0.017 min ^-1 and 0.012, respectively). The area under the receiver operating characteristic curve (AUC) of the BP-K ^trans (0.687) was highest among the single parameters and higher than that of the lesion-K ^trans (0.664). The combined logistic regression model of lesion-K ^trans , lesion-v _e , BP-K ^trans , BP-v _e , and BP-v _p had the highest AUC of 0.730.
Conclusion: Our results suggest that the contrast kinetic analysis of DCE-MRI data can be used to differentiate the malignant lesions from the benign and high-risk lesions among the indeterminate breast lesions recommended for MRI-guided biopsy exams.
Level of Evidence: 3 J. MAGN. RESON. IMAGING 2017;45:1385-1393.
(© 2016 International Society for Magnetic Resonance in Medicine.)