Cholesterol granulomas of the breast. A lesion which clinically mimics carcinoma

Cholesterol granuloma formation is an unusual development in the advanced stage of mammary duct ectasia. Its recognition is important because it can be clinically, mammographically, and grossly confused with carcinoma. Five such cases thought clinically to be carcinoma are presented. The histologic findings in cholesterol granuloma are distinctive and consist of multiple cholesterol crystals arranged either singly or in tightly-packed arrays. Foreign body giant cells surrounding the cholesterol deposits are invariably present.