Background: Breast cancer originates in breast tissue, which is made up of glands for milk production (lobules),  and  the  ducts  that  connect  lobules  to  the  nipple.  Breasts  contain  both  dense  tissue (glandular  tissue  and  connective  tissue,  together  known  as  fibro-glandular  tissue)  and  fatty  tissue. Fatty tissue appears dark on...