A hamartoma is a disorganised focus of a mature overgrowth of cells composed of tissue
elements of the organ in which it is found, and it can occur anywhere in the body. A breast
hamartoma is a rare, benign tumour consisting of fat, glandular and fibrous tissue, and is
known by various names such as lipofibroadenoma or fibroadenolipoma, depending on the
dominant tissue found within the lesion. The reported incidence is low (0.1% – 0.7%), but is
increasingly thought to be because of under-diagnosis of the condition.