Breast Cancer is a illness that causes cells in the breast to alter and grow in an uncontrolled pattern. Breast cancer is the most usual form of cancer in women, but there can be many different types of disease. Some people are born with defective cells, or may be more likely to be influenced by factors that may cause cells to grow out of control. Cells can change abnormally during a person’s lifetime; some cells may turn in to cancers, others are controlled and canceled by cells that regulate, or suppress, tumor development. Some breast cancers remain in one place and are not as much of a threat as cancers that are developing and growing rapidly or invading other locations of the breast. Cancer cells that line the milk ducts and are in the surface of lobular organs that produce milk are usual locations where breast cancer takes place. Most breast cancer begins and develops in the milk ducts. It can take about 20 years for breast cancer to develop. There can be factors inside and outside the body that causes the conditions for normal cells to alter to cancer. Not all cell changes in breast cells will transform to cancer.