Prevalence and clinical significance of incidental extra-mammary findings in breast magnetic resonance imaging: A retrospective study of 1070 patients.

ABSTRACT

PURPOSE: The purpose of this study was to analyze the prevalence of extra-mammary findings in magnetic resonance imaging (MRI). MATERIALS AND METHODS: Data from 1070 consecutive breast MRI studies was analyzed. MR-BI-RADS (Breast Imaging Reporting and Data System) was used to classify the risk category. RESULTS: According to MR-BI-RADS, 915 (85.5%) of 1070 women were classified into MR-BI-RADS categories 1-3, and 155 (14.5%) into MR-BI-RADS categories 4-5. MR-BI-RADS categories 4-5 had a 10-times higher risk for major extra-mammary findings (odds ratio 10.1, P<0.01). CONCLUSION: Extra-mammary findings are common and may have important clinical consequences.