Top Doctors editorial
Created by: Top Doctors editorial
Breast cancer (or breast cancer) arises when cells in the breast start to grow uncontrollably. These cells usually form a tumor that can often be seen on an x-ray or can be felt as a lump (mass or lump). The tumor is malignant (cancer) if the cells can grow by penetrating (invading) the surrounding tissues or spreading (metastasizing) to distant areas of the body. Breast cancer occurs almost exclusively in women, but men can also suffer from it.