Mammography is a safety net that saves thousands of lives each year, yet thousands more slip through that net (see Box 1-1). Many women who would benefit from mammography do not undergo regular screening. Others who do undergo regular screening develop breast cancers that were not detected by their mammography exam. Additionally, then there are others whom screening mammography is unlikely to benefit, such as those who have no access to treatment or whose breast cancer is unresponsive to treatment even when detected early.
The goal of screening for breast cancer is not to detect all breast abnormalities; the goal is to prevent deaths from breast cancer. Thus the benefits of mammography depend on the availability of effective treatment. Despite the common misconception, screening mammography does not benefit women by reducing their risk of breast cancer, but rather by reducing mortality through detecting breast cancer at earlier and more treatable stages.
In 2002, approximately 60.5 percent of women aged 40 to 64 received mammograms in the United States. Based on U.S. Census Bureau data for 2002, this means that:
An estimated 15,300 women aged 40 to 64 died of breast cancer in 2003.
The risk of breast cancer rises steeply with age, but the use of mammography screening increases much less with age. Approximately 63.8 percent of women 65 and over received mammograms in the United States in 2002. Based on Census Bureau data for 2002, this means that:
An estimated 23,000 women over 65 died of breast cancer in 2003.
It is generally several years from the time a lethal breast cancer is first detected and the time of death. In most cases, women who die of breast cancer in a particular year are not the same women who receive a screening mammogram or even are first diagnosed that year.
SOURCE: U.S. Census Data for July 2003; Cancer Prevention and Early Detection Facts and Figures, ACS 2004.