| Breast cancer is the most common form of cancer diagnosed in women in the United States, and the second most common cause of cancer death in women. In 2009, the American Cancer Society estimates that there will be 194,280 new cases of invasive breast cancer diagnosed and 40,610 deaths. Breast cancer is a clinically heterogeneous disease, and treatment depends on a number of characteristics of the disease. For example, breast cancers vary in their biologic characteristics, including hormone receptor status and HER2 status. It has become standard practice to assess the estrogen receptor, progesterone receptor, and HER2 status of tumor cells in breast cancer patients, and to base subsequent treatment decisions on these assessments. |
Autoimmune disease
Oncology
