Diagnosis of Breast Lesions on MRI using BI-RADS and Kaiser Score in Mass and Non-Mass Enhancement: Benefit of KS and KS+ for Different Readers

Motivation: Kaiser score (KS) could help diagnose lesions of breast MRI by an intuitive flowchart. Goal(s): To compare the diagnostic performance of BI-RADS and KS and to evaluate the benefit of the modified KS+ by incorporating diffusion. Approach: 630 patients were analyzed independently by three radiologists with different experiences, including 458 mass and 172 non-mass enhancement (NME) lesions. Results: KS outperforms the unstructured BI-RADS, especially for less experienced readers. The diagnosis for NME was more difficult than for masses, true for three readers regardless of the method used. The accuracy of KS+ was improved for masses, but not for NME. Impact: Kaiser Score provides an intuitive method for lesion interpretation, primarily helpful for mass lesions read by less experienced readers. KS+ is mainly applicable to mass lesions. For NME, the KS criteria need to be improved.