Breast cancer

Skip Navigation

Breast cancer happens when cells in your breast grow abnormally and out of control. The cancer cells can spread to other parts of your body.

You're more likely to get breast cancer as you get older.

Breast cancer is the second most common type of cancer in women. Men can also get breast cancer, but this is rare.




The Health Encyclopedia contains general health information. Not all treatments or services described are covered benefits for Kaiser Permanente members or offered as services by Kaiser Permanente. For a list of covered benefits, please refer to your Evidence of Coverage or Summary Plan Description. For recommended treatments, please consult with your health care provider.