Breast Cancer Risk in American Women

Many women are more interested in the risk of being diagnosed with breast cancer at specific ages or over specific time periods than in the risk of being diagnosed at some point during their lifetime. Estimates by decade of life are also less affected by changes in incidence and mortality rates than longer-term estimates. The SEER report estimates the risk of developing breast cancer in 10-year age intervals (1). According to the current report, the risk that a woman will be diagnosed with breast cancer during the next 10 years, starting at the following ages, is as follows: 

• Age 30 . . . . . .  0.49% (or 1 in 204)
• Age 40 . . . . . .  1.55% (or 1 in 65)
• Age 50 . . . . . .  2.40% (or 1 in 42)
• Age 60 . . . . . .  3.54% (or 1 in 28)
• Age 70 . . . . . .  4.09% (or 1 in 24)

These risks are averages for the whole population. An individual woman’s breast cancer risk may be higher or lower depending on known factors, as well as on factors that are not yet fully understood. To calculate an individual woman’s estimated breast cancer risk, health professionals can use the Breast Cancer Risk Assessment Tool, which takes into account several known breast cancer risk factors. 

For more information about the risk of developing breast cancer at specific ages, within specific time periods, and for different racial/ethnic groups, and the lifetime risk of dying from breast cancer see the SEER data table. The Know Your Chances Special Cancer Tables allows people to get information on their risk of breast and other cancers over several time frames based on their age, sex, and race.

For a woman born in the 1970s in the United States, the lifetime risk of being diagnosed with breast cancer, based on breast cancer statistics from that time, was just under 10% (or about 1 in 10). 

The last five annual SEER Cancer Statistics Review reports show the following estimates of lifetime risk of breast cancer, all very close to a lifetime risk of 1 in 8:

• 12.83%, based on statistics for 2014 through 2016  
• 12.44%, based on statistics for 2013 through 2015
• 12.41%, based on statistics for 2012 through 2014
• 12.43%, based on statistics for 2011 through 2013
• 12.32%, based on statistics for 2010 through 2012

SEER statisticians expect some variability from year to year. Slight changes may be explained by a variety of factors, including minor changes in risk factor levels in the population, slight changes in breast cancer screening rates, or just random variability inherent in the data.