Abstract
Myofibroblastoma of the breast (MFB) is a rare benign tumor of mesenchymal origin with only 80 cases reported in the literature so far. It most commonly occurs in elderly males and postmenopausal females and grows slowly over a period of months to years. In this study we describe a very rare case of a MFB in a premenopausal woman who presented with a rapidly growing breast mass. Diagnostic evaluation and management of the patient are discussed along with a review of the literature. We conclude that despite its rarity, myofibroblastoma should always be considered in the differential diagnosis of mesenchymal breast tumors. No specific imaging features have been described. Thorough immunohistochemical analysis is crucial to obtain a definitive diagnosis. Local excision is the treatment of choice.