Aside from cancers of the skin, breast cancer is the most common cancer among U.S. women.
A woman living in the United States has a one in eight lifetime risk of developing breast cancer, meaning that if every woman lived to age 85, one out of eight women would be diagnosed with breast cancer. While any woman can develop breast cancer, the chances increase with age.
The American Cancer Society estimates that for 2014:
- About 62,570 new cases of non-invasive breast cancer, in which the abnormal cells are confined to lobules (LCIS) or milk ducts (DCIS) only, will be diagnosed. DCIS may be a precursor to breast cancer, but because the cells have not spread the prognosis is positive; some proportion of the women will never develop breast cancer.
- About 232,670 new cases of invasive breast cancers will be diagnosed in women.
- About 40,000 women will die from breast cancer.
There are currently more than 2.8 million women living with breast cancer in the United States.
Men account for one percent of new breast cancer cases and breast cancer deaths (for 2014, that means approximately 2,360 men will be diagnosed with breast cancer and 430 men will die from it).
Probability of Developing Invasive Breast Cancer
Number of women who would receive a breast cancer diagnosis:
|Current Age (in Years)||Risk in Next 10 Years||Lifetime Risk of a Breast Cancer Diagnosis|
|30||1 in 250||1 in 8|
|40||1 in 71||1 in 9|
|50||1 in 42||1 in 9|
|60||1 in 29||1 in 11|
|70||1 in 27||1 in 15|
(Table 1 from Breast Cancer Diagnosis, Breast Cancer Screening (PDQ), National Cancer Institute.)
Breast cancer incidence in women is highest in the United States and in western and northern Europe. The lowest rates are in Asia and Africa, although incidence rates have been rising in areas such as Japan, Singapore and urban China. These regions are moving toward more Western economies and patterns of reproductive behavior.
The established risk factors for breast cancer do not account for all of the breast cancer cases. Despite the billions of dollars spent on breast cancer research, we still have much to learn about why some women develop breast cancer and others don’t.
Many people believe that the industrial processes and environmental damage that began during or after World War II play a major role in rising rates of breast cancer in Western countries. Research into environmental connections to breast cancer is the focus of organizations and foundations such as Breast Cancer Action and the Silent Spring Institute.
Starting in the 1970s, the incidence of breast cancer rose at alarming rates. Much of this long-term increase is believed to be due to delayed childbearing, having few children, and rising obesity rates. The widespread adoption of screening mammography also led to more cases being found, and the over-diagnosis of cancers that don’t need to be treated. (For more information, see Mammography Screening Guidelines.)
Between 2002 and 2003, there was a decrease in the incidence of breast cancer, particularly among women ages 50 to 69. This drop coincides with the release of research findings from the Women’s Health Initiative (WHI) study, which prompted many women to discontinue their use of hormone therapy.
Survival rates depend upon the kind of breast cancer. On average, long-term survival rates for women with breast cancer are: 89 percent at 5 years; 83 percent at 10 years; and 78 percent at 15 years.
Long-term survival rates are not a cure; a person is only considered cured if, after being diagnosed with breast cancer, she or he lives out a normal life span and dies of something else not caused by breast cancer treatment. Fewer than one in six women diagnosed with breast cancer die of the disease.