Leiomyosarcoma of the female breast.

Leiomyosarcomas of the breast are rare tumors. Less than 15 such cases have been reported in the literature so far. In this paper authors describe a case of leiomyosarcoma of a female breast presenting as a firm lobulated mass, mimicking a phylloid tumor radiographically. By fine needle aspiration biopsy, on the smears discohesive malignant looking cells were conclusive to a poorly differentiated invasive ductal carcinoma of the breast. The mastectomy specimen contained a lobulated mass, microscopically showing a partly epithelioid spindle cell tumor, immunoreactive for vimentin, desmin, smooth muscle actin antibodies, and negative for epithelial markers, hormone and growth factor receptors. Axillary lymph nodes were free of tumor. A primary leiomyosarcoma of the breast was diagnosed.