Solitary dilated duct visualised by mammography: ultrasound and anatomopathological correlation

To correlate solitary dilated ducts (SDDs) detected by mammography with ultrasound and histopathological findings of intraductal lesions and evaluate the association with invasive or in situ breast carcinoma. The secondary goal was to evaluate the prevalence of SDDs in screening and diagnostic mammography.

This prospective study of consecutive screening and diagnostic mammograms from March 2016 to March 2017 at a referral centre for the diagnosis and treatment of breast cancer was registered at clinicatrials.gov (NCT03161392). SDDs were recorded prospectively on mammography, and regardless of the findings' stability, the participants were recalled for targeted ultrasound to evaluate the intraductal content, which was submitted to histopathological analysis when heterogeneous content or masses were found. SDD stability was evaluated for 2 years. The categorical data are shown as frequency and percentage, and the comparisons were conducted using the chi-squared test.

A total of 9,035 mammograms were evaluated. SDDs were identified in 130 (1.43%) mammograms and 94 targeted ultrasound were conducted. In 22 cases, histological analysis were performed, and the main findings were fibrocystic changes (n = 14) and papilloma (n = 8). The main clinical and imaging characteristics associated with statistical significance (p < 0.05) were the presence of nipple discharge, intraductal masses, and calcifications on mammography.

SDDs visualised using mammography and without other associated findings should be complemented with targeted ultrasound to evaluate the intraductal content that shows benign histopathological results when papilloma is the most relevant finding. No cases of invasive or in situ breast carcinoma were found in this study.