In 1972, Arrigoni termed hamartoma of the breast as all swellings that are grossly circumscribed, encapsulated masses, composed of mammary ducts and prominent lobules admixed with varying amounts of fibrous and adipose tissue often misdiagnosed as fibroadenomas or mammary dysplasias, a protocol needs to be established with regard to the mammographic and pathological details that confirm the existence of these lesions as a distinct entity. Pathognomonic radiological findings help identify these lesions, confirmed later on tissue diagnosis.
Hamartomas form a rare and distinct group of benign breast lesions which are characterized by distinctive mammographic and pathological features, added to a high degree of clinical suspicion. They do not possess specific diagnostic histological features. The role of fine needle aspiration cytology and needle core biopsy in making the diagnosis is limited, and requires clinical and radiological correlation to avoid under diagnosis. The presence of fibrous tissue within the lobules, or fibrous tissue and fat in the stroma, with or without pseudoangiomatous changes, should alert the pathologist to the possibility of a hamartoma. Although hamartomas are benign, coincidental malignancy can occur, and the issue of potential recurrence has not been resolved.
We presented a case of mammary hamartoma in an 82-year-old female which was picked up on a chest CT scan, diagnosis was confirmed by mammogram, breast ultra sound scan as well as core biopsy.
Breast hamartoma is a rare entity, but whenever unfamiliar presentation of benign breast lesion is encountered with microcalcifications, this entity should be considered and coexistent malignancy should be ruled out.