Factors associated with false-negative Kaiser score results in breast magnetic resonance imaging

To evaluate the Kaiser score (KS) on magnetic resonance imaging (MRI) in patients diagnosed with breast cancer and to identify clinical, pathological, and radiological factors associated with false-negative Kaiser score.

This retrospective study included 120 histopathologically proven breast cancer masses. Non-mass enhancements were excluded. The KS of each lesion was determined based on MRI features. Clinicopathological features and imaging findings were also analyzed. Univariate and multivariate regression analyses were used to identify factors associated with false-negative KS results in breast cancer diagnosis.

One hundred eleven (92%) of the cases had a KS of 5 or higher, yielding a true-positive result. Nine (8%) had a score below 5, yielding a false-negative result. In univariate regression analysis, a history of breast cancer (p = 0.008), tumor size less than 2 cm (p = 0.001), and human epidermal growth factor receptor 2 (HER2) positivity (p = 0.049) were found to be statistically significantly associated with false-negative KS. In multivariate analysis, only tumor size was found to be associated with false-negative KS (p = 0.018).

The Kaiser score carries a risk of false-negative KS, especially in small tumors. Therefore, evaluation in conjunction with clinical risk factors, histopathological features, and additional imaging parameters is recommended. Furthermore, KS is a valuable decision-support tool in breast MRI.