Diagnostic Performance of DCE-MRI Breast Using Kaiser Score in Characterization of Mass and Nonmass Lesions and Its Comparison with ACR BI-RADS

Abstract

Introduction

Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) is a highly sensitive modality for the detection and characterization of breast lesions, yet its limited specificity and interpretative variability pose diagnostic challenges. The American College of Radiology Breast Imaging Reporting and Data System (ACR BI-RADS) provides a structured lexicon but lacks definitive guidance for certain lesion categories, particularly nonmass enhancements. The Kaiser score (KS), a semiquantitative decision-support tool, has emerged as a potential adjunct to standard interpretation and offers a structured approach to improve diagnostic accuracy.

Objectives

The study was aimed to evaluate the diagnostic performance of DCE-MRI of the breast by applying the KS in the characterization of mass and nonmass enhancement and its comparison with ACR BI-RADS.

Materials and Methods

Two radiologists assessed the KS and ACR BI-RADS on 103 sequential patients on 3-T DCE-MRI with 142 histopathologically verified lesions. The diagnostic performance of the KS was recognized through receiver operating characteristic (ROC) by the area under the ROC curve (AUROC). Cohen's kappa coefficient was used to evaluate the inter-reader agreement. These findings were compared and correlated with ACR BI-RADS.

Results

The KS has sufficiently high AUROC for all the lesions including mass and nonmass lesions (0.895, 0.955, and 0.622, respectively). The sensitivity of the KS was similar to that of ACR BI-RADS for both readers (93.6–91.5%) with a higher specificity of 85.4% compared with 62.5% for ACR BI-RADS. The improvement in specificity was also seen for mass as well as nonmass lesions. Excellent inter-reader agreement was observed with kappa values of greater than 0.9.

Conclusion

DCE-MRI using the KS showed high diagnostic accuracy as compared with ACR BI-RADS with an excellent inter-reader agreement. Thus, the KS in conjugation with ACR BI-RADS can enhance diagnostic accuracy and decrease experience-related variability.

Keywords

dynamic contrast-enhanced magnetic resonance imaging - breast cancer - ACR BI-RADS - Kaiser score

Patient's Consent

Patient consent is not required due to the retrospective nature of the study.

Publication History

Article published online:
10 July 2025

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