Lactation adenomas are benign breast tumors that occur in pregnant and breastfeeding women, as well as in the postpartum period. They belong to the adenomatous lesions of the breast and are caused by physiological changes in the breast due to hormonal changes during pregnancy and lactation. They usually appear as a soft, painless, movable tumor in the breast, often in its anterior parts, during pregnancy or the postpartum period. They can grow quickly and reach large dimensions, and can be multiple. The eventual appearance of pain and sudden acceleration of growth indicate infarction in the lesion.

In the postpartum period or after weaning, they often disappear or decrease in size, but they can recur in the next pregnancy. To reduce the size of the lesion after weaning, bromocriptine may be given. If the lesion does not disappear even then, surgical excision is indicated.

     The radiological method of choice when suspecting lactation adenoma is ultrasound, given that the patients are pregnant or lactating. A typical ultrasound finding indicates a benign lesion – sharply delineated, oval or slightly lobulated, homogeneous, hypoechoic or isoechoic, usually with posterior enhancement, compressible, and hypervascular; often with hyperechoic strands and sometimes with cystic zones (a sign of infarction and necrosis). They often cannot be distinguished from fibroadenomas. However, sometimes they can resemble a malignant tumor with their ultrasound characteristics. Because of their nonspecific characteristics, and for definitive histopathological diagnosis, biopsy is recommended.

     The differential diagnosis primarily includes fibroadenomas, which can significantly increase in size during pregnancy, as well as galactocele and other benign, but also malignant tumors during pregnancy. In case of infarction and subsequent pain, they can resemble an infected galactocele, abscess, or high-grade malignant tumor.