Postexcisional breast magnetic resonance imaging in patients with breast cancer: predictable findings of residual cancer

OBJECTIVE: The purposes of this study were to present magnetic resonance imaging (MRI) findings in patients with breast cancer soon after the excisional biopsy and before definitive surgery and to assess the diagnostic accuracy of MRI for prediction of residual cancer. METHODS: Breast MRI was performed on 51 patients with breast cancer diagnosed by excisional biopsy. The morphologic type of postexcisional site was categorized into regular thin rim enhancement (P1), peripheral nodular enhancement (P2), satellite nodule within 2 mm from the cavity margin (P3), and irregularly thickened wall enhancement (P4). Enhancement pattern was categorized into "washout," "plateau," and "progressive" enhancement. All patients underwent definitive surgery after MRI. Magnetic resonance imaging findings were correlated with the pathologic findings. RESULTS: The sensitivity, specificity, accuracy, positive predictive value and negative predictive value of MRI for prediction of residual cancer were 92.1%, 69.2%, 78.4%, 88.6%, 56.3%, respectively.ope