Breast Cancer

Cancers are a group of diseases that cause cells in the body to change and grow out of control. Most types of cancer cells form a lump or mass called a tumor, and are named after the part of the body where the tumor first starts. Breast cancer begins in breast tissue, which is made up of glands for milk production, called lobules, and the ducts that connect lobules to the nipple. The remainder of the breast is made up of fatty, connective, and lymphatic tissue. Most types of tumors that form in the breast are benign; that is, they are not cancer at all. Benign breast tumors are abnormal growths, but they do not grow and spread like cancer does, and are not life threatening. Some breast tumors are cancerous, but are called in situ, because they have not spread beyond the area where they began. In situ breast cancers are confined within the ducts or lobules of the breast. Excluding cancers of the skin, breast cancer is the most common cancer among women, accounting for nearly one of ever...