Cancer that comes back where it first started or cancer that has spread to another part of the body. For example, breast cancer cells may recur in the breast area or spread (metastasize) to the lung. When this happens, the disease is called recurrent or metastatic breast cancer. The return of cancer in the breast and the spread of cancer in the lung is called a secondary cancer.
For more information, see Breastcancer.org's Recurrent and Metastatic Breast Cancer section.