Abstract
This paper deals with a patient who received an excisional biopsy with a diagnosis of a fibroadenoma which was histologically diagnosed as stromal sarcoma of the breast, and additional excision of it yielded the definite pathological diagnosis of dermatofibrosarcoma protunberans originated in the skin of the breast. The patient was a 41-year-old woman. She had visited another hospital because of a left breast tumor in August 2004 and had been followed with a diagnosis of a fibroadenoma. In October 2005, she felt an increase of the breast tumor and underwent an excisional biopsy which gave a diagnosis of stromal sarcoma of unknown origin. Thus the patient was seen at our hospital for further treatment. We performed additional resection aiming at radical treatment. It was difficult to determine the resected tumor macroscopically, but microscopical study disclosed the tumor remnant in the dermis and supramammary fatty tissue of the resected material. Based on the localization of the lesion and positive reaction of it to CD34 immunohistologically, dermatofibrosarcoma protunberans originated in the breast skin was definitely diagnosed.
The disease presents difficulties in making differentiation from a fibroadenoma or a stromal tumor of the breast, and thus careful attitude for the diagnosis would be important.
