Breast leiomyoma.

Smooth muscle neoplasms exist as a spectrum of pathologic processes ranging from benign leiomyoma to anaplastic leiomyosarcoma. Although these tumors typically occur in regions where there is an abundance of smooth muscle, they may also be derived from the muscularis of the gastrointestinal tract or the media of blood vessels. The majority of breast leiomyomas are contiguous with the muscular components of the nipple areolar complex. Strong, in 1913, is credited with the early descriptions of leiomyoma of the mammary gland. There have been relatively few reports of this entity since Strong's initial description. Smooth muscle neoplasms of the breast present unique clinical challenges for which therapeutic decisions are based on criteria extrapolated from the management of similar tumors at other sites. This report high-lights key clinical and pathologic findings in a postmenopausal woman with a discrete breast mass of benign smooth muscle histology.