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About The Breast
What is Breast Cancer?
Breast Cancer
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What is Breast Cancer?
You've heard the term "breast cancer" before, but what does it mean? Cancer occurs when cells in a part of the body begin to grow out of control. Although there are many kinds of cancer, they all come about because of out-of-control growth of abnormal cells. Different kinds of cancer can behave very differently. For example, lung cancer and breast cancer are very different diseases. They grow at different rates and respond to different treatments. That's why people with cancer need treatment that is aimed at their kind of cancer.
Most cancers are named after the part of the body where the cancer first starts. Breast cancer begins in the breast tissue. While it usually affects women, men can also get breast cancer, although this is rare.
Inside the breasts are glands that produce and release milk after a woman has a baby. The glands that make the milk are called lobules and the tubes that connect them to the nipple are called ducts. The breast itself is made up of lobules, ducts, and fatty, connective, and lymphatic tissue.
Lymph is a clear fluid that contains immune system cells and tissue waste products. The fluid is carried in lymph vessels that lead to small, pea-sized collections of tissue called lymph nodes. Most lymphatic vessels of the breast lead to lymph nodes under the arm. They are called axillary nodes.
When breast cancer cells reach the underarm lymph nodes and continue to grow, they cause the nodes to swell. If cancer cells have reached these nodes, they are more likely to spread to other organs of the body as well.
There are several types of breast tumors. Most are benign; that is, they are not cancer. Benign breast tumors are abnormal growths, but they do not spread outside of the breast and they are not life threatening.
Some lumps aren't really tumors at all. These lumps are often caused by fibrocystic changes. Cysts are fluid-filled sacs, and fibrosis refers to the formation of connective tissue or scar tissue. Fibrocystic changes can cause breast swelling and pain. The breasts may feel lumpy and sometimes there is a clear or slightly cloudy nipple discharge.