Malignant Fibrous Histiocytoma of Breast

The patient was a 60 y/o woman who presented with a 6.0 cm right breast mass. The tumor had a somewhat gritty cut surface. Twenty right axillary lymph nodes were negative for metastases. The tumor is composed of spindle cells arranged with a storiform growth pattern. There is marked nuclear pleomorphism and atypical mitotic figures are present. Chronic inflammatory infiltrate is present in the background.