This irregular tan mass in the breast is a carcinoma. The gross appearance seen here is a cut section from a mastectomy specimen. Microscopically this neoplasm proved to be an infiltrating ductal carcinoma. In the microscopic view seen here from the dermis overlying the breast, there is perineural invasion. The risk for breast cancer lifetime for women living in the U.S. is at least 1 in 10. Breast self-examination, physical examination by health care workers, and mammography can aid in identifying these tumors, hopefully before they have reached the size seen here, when metastases are much more likely to have occurred.