What is the role of breast MRI in the management of women with pathologic nipple discharge and normal conventional imaging?

Abstract

To investigate the diagnostic performance of breast MRI in revealing mammographically and sonographically occult lesions requiring excision in patients with pathologic nipple discharge. In this retrospective study, 57 women with pathologic nipple discharge who had normal or inconclusive mammography and ultrasonography results and underwent breast MRI were determined. Patients who had histopathological diagnosis or ≥ 1-year imaging follow-up were included. MRIs were classified as positive and negative according to final BI-RADS assessment categories. Diagnostic performance of MRI, including sensitivity, specificity, negative predictive value, and positive predictive value, was calculated for detecting both malignancy and lesions requiring surgery. Abnormal contrast enhancement on the pathologic nipple discharge side was detected in 29 MRIs (50.8%), categorized as BI-RADS 4. Abnormal findings were solid masses in 17 cases (58.6%) and non-mass enhancement in 12 cases (41.3%). Despite normal conventional imaging results, 4 malignant lesions and 16 lesions requiring surgery were detected with MRI. The sensitivity and specificity of MRI for detecting lesions requiring surgery were 100% and 68.2%, respectively. The positive predictive value (PPV) and negative predictive value were 55.1% and 100%, respectively. In conclusion, this study confirmed that MRI is a reliable tool to detect lesions requiring surgery in patients with pathologic nipple discharge. MRI should be used in routine workup in patients with normal conventional imaging and imaging follow-up can be safely applied in patients with negative MRI.