What Causes Breast Cancer?


What Causes Breast Cancer?

In order to prevent breast cancer from occurring we must understand what causes it to begin and what causes it to grow. Ultimately all breast cancer is "genetic." It does not mean that everyone who is diagnosed with breast cancer has had a relative affected by breast cancer. In fact, only 25% of all women or men diagnosed have a positive family history. It means that in breast cancer cells there is a change in the genes that control the cells growth and division. Once altered, the cells begin to divide in a "chaotic" or disorganized manner forming a mass or a cancerous growth.

Not all cancers grow at the same rate. Some are very rapidly dividing tumors and others may take years to become evident on mammography or on clinical exam. There are many factors that play a role in the growth and development of breast cancer. 

Although genetics plays a role in all cancers, one single genetic alteration is not enough for a cancer to form. Even women with BRCA-1 and BRCA-2 gene alterations are not guaranteed to develop cancer. They are clearly at a much greater risk for the development of breast and ovarian cancer but other factors still come into play. Women who test positive for the BRCA-1 and BRCA-2 genes have an 80 to 90% chance of developing cancer. But this gene alteration accounts for only 5 to 9% of all breast cancers diagnosed. Other internal and external factors are involved in the formation of a cancer.