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 ), interstitial volume fraction (v ), and vascular volume fraction (v ) 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 (0.081 min ), higher median BP-K (0.032 min ), and BP-v (0.020) than those without malignant lesions (0.056 min , 0.017 min and 0.012, respectively). The area under the receiver operating characteristic curve (AUC) of the BP-K (0.687) was highest among the single parameters and higher than that of the lesion-K (0.664). The combined logistic regression model of lesion-K , lesion-v , BP-K , BP-v , and BP-v 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.