Diagnostic accuracy of subjective kinetic assessment of masses in contrast-enhanced mammography in comparison with contrast-enhanced magnetic resonance imaging

Background Contrast-enhanced MRI (CE MRI) of the breast is currently the most sensitive imaging technique for detecting invasive breast cancer, and it provides both morphologic and functional information through kinetics for characterizing breast masses. Contrast-enhanced mammography (CEM) uses the same principle of neo-angiogenesis to detect early cancers similar to MRI with comparable diagnostic performance. However, there is an important limitation in CEM in characterizing the breast lesions because of the non-availability of kinetic information. To the best of our knowledge, very few studies have assessed the CEM kinetics. In this study, we have evaluated the accuracy of subjective assessment of contrast kinetics in CEM and compared it with the subjective and quantitative kinetic assessment in CE MRI. If the performance of CEM is comparable to MRI, it may add an additional dimension to CEM in characterizing the breast masses in addition to detection. Results Kinetic information of 123 lesions in 90 patients was analyzed in CEM and MRI. Of these, 26 (21.1%) were benign, 4 (3.3%) were high risk lesions, and 93 (75.6%) were malignant breast lesions. Comparison of subjective and quantitative assessment in CE MRI had almost perfect agreement with a kappa value of 0.816, and both were used as reference standards for comparing CEM kinetics. Comparison of subjective assessment of kinetic patterns in CEM using only CC and MLO views showed moderate agreement with both quantitative (kappa − 0.483) and subjective (0.547) CE MRI kinetics. When the delayed image obtained at 8 min was included for kinetic analysis, CEM kinetics showed substantial to almost perfect agreement with quantitative (kappa − 0.673) and subjective (kappa − 0.855) CE MRI kinetics, respectively. Conclusion We hope that this study results would encourage the breast radiologist to assess the kinetic information from CEM and use CEM as a single, simple and cost-effective imaging modality in detecting and characterizing breast masses.