Breast fibromatosis response to tamoxifen: dynamic MRI findings and review of the current treatment options.

Breast fibromatosis is a rare entity responsible for 0.2% of all solid breast tumors. It has been associated with scars, pregnancy, implants, and familial adenomatous polyposis. We present an interesting case of breast fibromatosis in a 29 year old woman which encroached upon her saline implant and subsequently filled its cavity once the implant was removed. The patient was put on tamoxifen therapy and at 14 month follow-up there was a significant decrease in the size of the mass. Dynamic MRI images are offered for review and current treatment options are discussed.