Myofibroblastoma of the Breast.

This study aimed presenting a case of a 64-year-old woman with a rare diagnosis of myofibroblastoma (MFB). MFB is one of the rare, benign, spindle-like stromal tumors arising from the connective tissue of the breast. MFBs are often confused with fibroadenomas and hamartomas because of their benign characteristic appearance on breast imaging and are diagnosed after excisional biopsies. Their differential diagnosis with malignant neoplasia of the breast is important because of their wide morphological spectrum. Our case also demonstrated a breast mass with benign imaging characteristics and a needle core biopsy revealing a benign, spindle-like stromal tumor. The pathological examination performed after the excision of the lump demonstrated a collagenous-/fibrous-type MFB. This case report emphasizes the rare but important place of MFB variants of the breast in the differential diagnosis of breast mass.