Breast Ultrasound during Lactation: Benign and Malignant Lesions

Abstract

Background: Structural changes during lactation make breast physical examination difficult. When breast problems occur, patients are often referred for an ultrasound (US) scan. Most breast lesions diagnosed in these patients are benign, but the diagnosis of breast cancer is a challenge. We aim to demonstrate the spectrum of US imaging findings in lactating women. Methods: 77 breastfeeding patients who underwent breast US in our department between February 2012 and March 2017 were evaluated. Patients' electronic medical records were reviewed for the presenting complaint, US reports, pathology results if available, and clinical/radiologic follow-up. All examinations were performed by 2 radiologists. Results: 28 of the 77 patients had normal US findings. Cysts were seen in 16 patients. 4 patients had stable fibroadenomas. 6 patients had US imaging findings suggestive of mastitis, 5 patients had galactoceles, 1 patient had an abscess, and 1 patient had unilateral hypertrophy without any accompanying lesion. In 13 patients, BI-RADS 3 solid masses were diagnosed. Invasive breast cancer was diagnosed in 3 patients. Conclusion: US can demonstrate or exclude a true mass against the background of a nodular breast parenchyma. Radiologists must be aware of malignant US features to avoid delays in the diagnosis of pregnancy-associated breast cancer.