What Happens

Breast cancer occurs when cells in the breast grow abnormally. As the breast cancer grows, it can spread to nearby tissues and lymph nodes. Advanced breast cancer can affect the bones, liver, and brain. Fortunately, when found at an early stage, breast cancer is highly curable.

Your doctor will learn more about how your breast cancer may behave when the cancer cells are examined under the microscope. This is called classification. It tells your doctor how rapidly the cancer cells are growing and dividing and where they may have started in the breast tissue. Tests for hormone receptors and other markers are also done. All of this information will help you and your doctor make decisions about treatment.

The stage indicates how far the cancer has spread within the breast, to nearby tissues, and to other organs. Your doctor will determine the stage of your breast cancer by gathering information from other tests, such as axillary lymph node surgery, blood tests, bone scans, and X-rays. The stage of your cancer is one of the most important pieces of information that will help guide your treatment options.