Breast Cancer Statistics
Breast cancer incidence in women in the United States is 1 in 8 (about 13%).In 2009, an estimated 192,370 new cases of invasive breast cancer were expected to be diagnosed in women in the U.S., along with 62,280 new cases of non-invasive (in situ) breast cancer.About 1,990 new cases of invasive breast cancer will be diagnosed in men in 2008. Less than 1% of all new breast cancer cases occur in men.Following a 20-year increase in breast cancer incidence rates in women, 1999-2006 saw these rates decrease by 2%. One theory is that this decrease was due to the reduced use of hormone replacement therapy (HRT) by women after the results of a large study, called the Women’s Health Initiative, were published in 2002. These results suggested a connection between HRT and increased breast cancer risk.About 40,170 women in the U.S. were expected to die in 2009 from breast cancer, though death rates have been decreasing since 1990. These decreases are thought to be the result of treatment advances, earlier detection through screening, and increased awareness.For women in the U.S., breast cancer death rates are higher than those for any other cancer besides lung cancer.Besides skin cancer, breast cancer is the most commonly diagnosed cancer among U.S. women. More than 1 in 4 cancers are breast cancer.Compared to African American women, white women are slightly more likely to develop breast cancer, but less likely to die of it. One possible reason is that African American women tend to have more aggressive tumors, although why this is the case is not known. Women of other ethnic backgrounds — Asian, Hispanic, and Native American — have a lower risk of developing and dying from breast cancer than white women and African American women.As of 2008, there are about 2.5 million women in the U.S. who have survived breast cancer.A woman’s risk of breast cancer approximately doubles if she has a first-degree relative (mother, sister, daughter) who has been diagnosed with breast cancer. About 20-30% of women diagnosed with breast cancer have a family history of breast cancer.About 5-10% of breast cancers are caused by gene mutations inherited from one’s mother or father. Mutations of the BRCA1 and BRCA2 genes are the most common. Women with these mutations have up to an 80% risk of developing breast cancer during their lifetime, and they often are diagnosed at a younger age (before age 50). An increased ovarian cancer risk is also associated with these genetic mutations. Men with a BRCA1 mutation have a 1% risk of developing breast cancer by age 70 and a 6% risk when they have a BRCA2 mutation.About 90% of breast cancers are due not to heredity, but to genetic abnormalities that happen as a result of the aging process and life in general.The most significant risk factors for breast cancer are gender (being a woman) and age (growing older).
