US of a 38-year-old lactating woman (postpartum 6 months) with a galactocele. US of the breast reveal an irregular-shaped, hypoechoic mass in the left subareolar area (white arrows). Part of the mass shows spiculation. Under the diagnosis of category 4A, a core biopsy was performed, and the pathology result was fibrocystic changes, compatible with a galactocele.