What Is Breast Cancer?
Cancer is caused by malignant (cancerous) cells that grow and multiply without control. Cancer that begins in any part of the breast is called breast cancer.
In breast cancer, the malignant cells can develop in the lobules or glands that make breast milk; this is known as lobular carcinoma.
Or, the cancer cells can start in the ducts or tubes that carry the milk to the nipple; this is known as ductal carcinoma.
According to American Cancer Society estimates for 2014:
• Breast cancer is the second-most common form of cancer in American women