Abstract: | A case of an unusual breast tumor is described in which the smear from a fine needle aspiration (FNA) biopsy caused difficulty in differentiating between a spindle-cell carcinoma and a sarcoma. The problem was resolved by the immunoperoxidase demonstration of epithelial membrane antigen (EMA) in the cells, thus enabling a definitive diagnosis of spindle-cell carcinoma to be made. This case further demonstrates the utility of demonstrating EMA in FNA specimens to distinguish between epithelial and nonepithelial neoplasms. |