A case of dermatofibrosarcoma protuberans in the skin over the breast of a young woman

A 19-year-old woman with dermatofibrosarcoma protuberans (DFSP) of the breast is described. She presented with a tumor of the left breast with redness and swelling. She had noticed a small tumor five years previously, but it had begun to grow rapidly three months previously. Mammography, ultrasonography and aspiration biopsy cytology demonstrated an apparently benign tumor of the breast preoperatively. Wide excision was performed to confirm the diagnosis. Histologically, the tumor was composed of a uniform population of fibroblasts in a distinct storiform pattern. DFSP was diagnosed in the skin over the breast. This lesion ordinarily originates from the dermis in the trunk and proximal extremities. It is important to diagnose a soft tissue lesion accurately when it occurs in the breast.