The attention of physicians was directed to traumatic fat necrosis of the breast by Lee and Adair1in 1920, and again in 1922. Clinically, these tumors present many features commonly associated with carcinoma. They are hard; they may be fixed to the skin or deeper structures; there may be retraction of the nipple and enlarged axillary lymph nodes. Two characteristics which have to date constantly been described in all cases are the history of trauma and the corpulence of the patient. A certain number of malignant tumors, variously estimated at from 3 to 39 per cent., give a distinct traumatic history, so that there is nothing pathognomonic of traumatic fat necrosis except the histologic picture. The nature of the trauma as the etiologic factor in this case of breast tumor is the reason for this report. REPORT OF CASE Mrs. S. H., aged 35, was referred because of a