Breast cancer is a disease characterized by cells in the breast that become abnormal and multiply uncontrollably, forming a tumor. If left untreated, malignant cells may eventually spread beyond the original tumor to other parts of the body, a process called metastasis. Breast cancer is a disease with many types. Each type of breast cancer is identified by the cells in the breast that become malignant. Hormones also play a role in the development of certain types of breast cancer. Signs of breast cancer include skin changes, pain, nipple discharge, a lump and other symptoms. Breast cancer affects hundreds of thousands of women around the world each year. In the United States alone 246,660 women are estimated to receive a breast cancer diagnosis every year. That is 1 in every 8 women. Around 40,000 American women die of breast cancer every year. However, breast cancer survival rates look encouraging, especially if the disease is detected early. Since 1990, breast cancer survival rates have been increasing. Due to better screening practices, increased public awareness and early detection, and improved technology and treatments, mortality in women aged 50 and older has been declining significantly for the past 2 decades. In the U.S. there are currently over 2.8 million breast cancer survivors.
Breast cancer occurs in two broad categories: noninvasive and invasive.
Some other types of breast cancer include, but are not limited to: Paget's disease of the nipple, sarcoma of the breast, medullary carcinoma, tubular carcinoma, mucinous carcinoma, metaplastic carcinoma, adenocystic carcinoma, phyllodes tumor and angiosarcoma.
- Noninvasive (in situ) breast cancer: Cancerous cells remain in a particular location of the breast, without spreading to surrounding tissue, lobules or ducts.
- Invasive (infiltrating) breast cancer: Cancerous cells break through normal breast tissue barriers and spread to other parts of the body through the bloodstream and lymph nodes.
Some other types of breast cancer include, but are not limited to: Paget's disease of the nipple, sarcoma of the breast, medullary carcinoma, tubular carcinoma, mucinous carcinoma, metaplastic carcinoma, adenocystic carcinoma, phyllodes tumor and angiosarcoma.