Benign lesions often will move relative to the surrounding tissue. Fibroadenomas are sometimes so mobile that when they are pressed they will flip from under your finger adn temporarily disappear. Benign lesions such as FBC and small simple cysts will sometimes enlarge as a woman approaches menses and subside afterwards. This indicates that they are stimulated by elevated levels of female hormones prior to her period and then regress when hormone levels fall. Cancers are unlikely to respond this way.
Simple cysts are often compressible and feel relatively soft .
As the amount of fluid in the cyst increases it can get quite firm. Fibroadenomas often have a rubbery feel to them. Cancers usually feel quite hard. Breast cancers are rarely tender to touch . Sometimes they may seem tender but this is really due to tender overlying breast tissue.