Objective: The purpose of this study is to assess the outcomes of symptomatic and asymptomatic solitary dilated ducts detected on mammography, ultrasound, and MRI.
Methods: All cases of isolated solitary dilated ducts between January 1, 2009 and December 31, 2016 in non-lactating females were reviewed. Clinical data, including patient's age, breast cancer history, and pathology results were collected. Imaging was reviewed, and indication for the exam, breast density, maximum diameter of the dilated duct on ultrasound, presence of an intraductal mass, presence of intraductal vascularity, presence of intraductal echogenicity, and subareolar or peripheral location of the dilated duct were recorded.
Results: 87 cases of solitary dilated ducts were assessed in this study, of which 3 were malignant, resulting in a positive predictive value of 3.5% (3/87). No malignancy was identified in asymptomatic screening patients. The three malignant cases were seen in patients presenting with a palpable lump (n = 1) or bloody nipple discharge (n = 2). There was a statistically significant association observed between the dilated duct diameter (p = 0.049) and presence of intraductal vascularity (p = 0.0005) with presence of malignancy.
Conclusion: Rate of malignancy is low in solitary dilated ducts, especially among asymptomatic patients. Patient's presenting with clinical symptoms, larger dilated duct diameters, and/or intraductal vascularity may require additional evaluation including biopsy to exclude malignancy.
Advances in knowledge: Clinical and imaging factors can assist in better identifying patients with solitary dilated ducts who should undergo biopsy.