More than 180,000 women are diagnosed with breast cancer each year. Cancer is a group of diseases that occur when cells become abnormal and divide without control or order. Each organ in the body is made up of various kinds of cells.
Cells normally divide in an orderly way to produce more cells only when they are needed.
This process helps keep the body in good health. If cells divide when new cells are not needed, they form too much tissue. This extra tissue, called a tumor, can be benign or malignant. Eighty percent of all breast tumors are benign. Benign tumors are not cancer.