Fat necrosis of the breast: a cytological and clinical study.

Fat necrosis of the breast is a sterile condition that usually results from trauma to the breast. It may present with a breast lump that, on clinical and mammographic examination, can mimic malignancy. The literature suggests that fat necrosis of the breast can only be diagnosed accurately by histological examinations of breast biopsies. In this paper, we review the findings of a series of 35 patients in whom fat necrosis was diagnosed on fine needle aspiration cytology. Repeated fine needle aspiration cytology with close follow-up have proven to be a reliable method of establishing the diagnosis of fat necrosis of the breast, thereby reducing the necessity for open biopsy.