Solitary fibrous tumor of the breast and mammary myofibroblastoma: the same lesion?

Benign stromal tumors of the breast are rare mesenchymal neoplasms that have significant clinical and morphologic overlap. We report the case of a spindle cell tumor occurring in the mammary gland with mixed features of solitary fibrous tumor and mammary myofibroblastoma. The significance of this finding as well as the pathologic and radiologic diagnostic strategies used to differentiate these two lesions are presented based on a review of pertinent literature.