Role of contrast-enhanced mammogram as an adjunct to tomosynthesis in evaluation of circumscribed breast lesions.

Abstract

We evaluated the role of contrast-enhanced mammogram (CEM) in the characterization of circumscribed lesions detected in digital breast tomosynthesis (DBT) and correlated with histopathology. A retrospective study was done on 205 circumscribed breast masses detected with DBT and for whom CEM was done before core biopsy/excision biopsy. Morphology of lesion enhancement was noted at a 2-min CEM image and depending on the enhancement pattern, they were classified as benign, malignant, and indeterminate. Indeterminate lesions were further characterized by contrast kinetics at 8 min and divided into benign and malignant lesions. The results were correlated with histopathology reports. Among the 205 lesions, 158 were benign and 47 were malignant by histopathology. All 47 malignant cases were diagnosed as malignant (sensitivity-100%) and 150 out of 158 benign lesions were diagnosed as benign by CEM (specificity-95%). Eight benign lesions were reported as malignant (false positive) by CEM. Positive predictive value was 85.4% (47/55); negative predictive value (NPV) was 100% (150/150); accuracy was 96% (197/205). The high sensitivity of CEM in our study suggests that CEM helps in the early diagnosis of benign-looking circumscribed breast malignancies. The high NPV of CEM helps to avoid unnecessary biopsies and interventions in benign lesions. This study describes the contrast enhancement pattern of benign and malignant circumscribed breast lesions and thereby helps in the diagnosis of malignancy at an early stage. CEM is a promising adjunct tool since it offers functional imaging as a supplement to anatomical imaging by DBT.