Myofibroblastoma (MFB) is a benign neoplasm of the mammary stroma composed of spindle shaped myofibroblasts. The neoplastic cells are arranged in short, intersecting fascicles embedded in a collagenous stroma. Mitoses are rare. The stroma may contain mast cells. Necrosis is usually absent. Entrapment of mammary ducts or lobules does not occur. MFB is an expansile tumour with pushing borders. It typically presents as a solitary, well circumscribed, slowly growing nodule measuring between 0.9 and 10 cm.
Myofibroblastoma of the breast is a rare tumour with only few reported cases. It occurs in both female and male patients between 40 and 87 years of age. Recommended treatment is tumourectomy
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