Dynamic high-spatial-resolution MR imaging of suspicious breast lesions : Diagnostic criteria and interobserver variability

OBJECTIVE. Our study was undertaken to develop diagnostic rules and to assess the reproducibility of dynamic and morphologic parameters for the characterization of suspicious breast lesions using dynamic high-spatial-resolution MR imaging.MATERIALS AND METHODS. Fifty-seven patients with suspicious mammographic or palpable findings underwent preoperative contrast-enhanced MR imaging of the breast using a three-time-point method of acquisition. Each lesion was prospectively analyzed by two independent radiologists for morphologic and visual dynamic enhancement characteristics. A classification and regression tree was used to examine the optimal order, cutoff points, and combination of imaging parameters to build a diagnostic rule separating benign from malignant lesions using histopathology findings as the standard of reference. Kappa statistics were used to determine observer variability.RESULTS. Among 23 benign and 34 malignant lesions (12 invasive, three ductal carcinoma in situ, and 19 mixed cancer), ma...