Breast cancer is the second most common form of cancer in women, following only non-melanoma skin cancer. As of 2006, more than 191,000 women were diagnosed, according to the Centers for Disease Control and Prevention (CDC). While no specific cause is known, a number of risk factors are.
Being a Woman
Breast cancer occurs in both men and women. However, it is approximately 100 times more common in women, according to the American Cancer Society.
Age
The older a woman is, the greater her risk for developing breast cancer. The Mayo Clinic reports that women over the age of 60 are more prone to this disease than younger women. The American Cancer Society agrees, explaining that approximately two out of three women with invasive breast cancer are 55 or older when the cancer is found.
Personal History of Breast Cancer
Women with a previous history of breast cancer have a greater risk of developing a new cancer either in the other breast or in another area of the breast where the first cancer was located. This differs from recurrent cancer, which is the original cancer returning in the original breast.
Inherited Genes
Approximately 5 to 10 percent of breast cancers may have a link to inherited gene mutations -- changes in genes -- that are passed down through each generation, according to the American Cancer Society. However, two specific mutated genes greatly increase a woman's risk of developing breast cancer -- BRCA1 and BRCA2. The American Cancer Society explains that women with either of these genes have an 80 percent chance of developing this disease during their lifetimes.
Family History
A woman who has a blood relative with breast cancer faces a greater risk of developing breast cancer. This relative can be from either her mother or father's side. However, her risk doubles when the relative is her mother, sister or daughter.
