Fat Necrosis: Correlation of Imaging Findings and Histopathology

Abstract Fat necrosis is an inflammatory response arising from damage to adipose tissue. Fat necrosis is a commonly encountered benign entity in breast imaging and has a wide spectrum of imaging appearances. Although fat necrosis is most commonly seen after intervention or trauma, it may be idiopathic. Given the overlap in imaging characteristics between fat necrosis and malignancy, understanding the various manifestations of fat necrosis can aid accurate diagnosis and help avoid unnecessary biopsy. We describe the range of imaging characteristics, including both classic benign imaging features and nonspecific features that can look worrisome for malignancy. Finally, we describe the radiologic-pathologic correlation of fat necrosis in the breast since biopsy with pathology is the gold standard for diagnosis in equivocal cases.