Sections View Full Chapter Figures Tables Videos Annotate Full Chapter Figures Tables Videos Supplementary Content + Download Section PDF Listen ++ For further information, see CMDT Part 17-04: Fat Necrosis + Key Features Download Section PDF Listen +++ ++ Rare In the past, most fat necrosis was seen after trauma, but now fat necrosis is commonly seen after fat injections to augment breast size or fill defects after breast surgery Also occurs after breast surgery, segmental resection, radiation therapy, or postmastectomy flap reconstruction + Clinical Findings Download Section PDF Listen +++ ++ Breast mass Often associated with skin or nipple retraction Usually indistinguishable from cancer even with imaging studies + Diagnosis Download Section PDF Listen +++ ++ Core needle biopsy usually adequate for diagnosis Differential diagnosis Breast cancer Fibroadenoma Breast abscess Fibrocystic condition of breast Paget disease of the breast + Treatment Download Section PDF Listen +++ ++ If untreated, mass gradually disappears