Home » Galleries » Breast » Myofibroblastoma of the breast

Myofibroblastoma is a benign tumour derived from myofibroblasts. It is a relatively uncommon breast tumour that can be found in both men and women. Microscopically it is composed of spindle cells arranged in haphazard and intersecting fascicles interrupted by thick bands of collagen, and variable amounts of adipocytes. The neoplastic cells show diffuse staining for desmin and CD34 with variable positivity for SMA, BCL2, CD99, CD10, ER, PR, and AR. It can often resemble a spindle cell lipoma.