Second-look breast ultrasonography after galactography in patients with nipple discharge

Aim: The objective of this study was to evaluate the diagnostic performance of second-look breast ultrasound (US) immediately after galactography in patients with nipple discharge. Materials and methods: Between January 2010 and November 2018, 89 patients with nipple discharge were retrospectively analyzed. All patients were examined by galactography and US. US was performed twice, before and after galactography. Galactography, mammography and US findings were categorized according to the Breast Imaging Reporting and Data System (BI-RADS). The final diagnosis was established by histopathological examination. Results: Out of 89 patients, 25 (28.1%) patients had positive findings as evident by US before galactography. Forty-eight (53.9%) patients had positive findings as demonstrated by galactography. Fifty-nine (66.3%) patients had positive findings as evident by second-look US after galactography (13 patients with benign, 37 with borderline and 9 with malignant lesions). Second-look US after galactography showed the highest diagnostic accuracy (83.2%), sensitivity (95.8%) and negative predictive value (93.3%) for borderline and malignant lesions. For the detection of malignant lesions, second-look US after galactography showed the highest sensitivity (90%) and negative predictive value (96.7%). Agreement between imaging and histological result using Bland-Altman analysis exhibited no significant difference between the size established by ultrasound and galactography. Conclusion: The second-look US after galactography is a powerful diagnostic tool for the detection of lesions in patients with nipple discharge and demonstrates high diagnostic accuracy, sensitivity and negative predictive value.