The Who, What, Where, When and Sometimes, Why.

Race and Ethnicity

Rates of breast cancer in the U.S. vary by race and ethnicity.

White women and black women have the highest incidence (rate of new breast cancer cases) overall [611]. American Indian and Alaska Native women have the lowest incidence (see Figure 2.3 below) [611].

Figure 2.3

 Figure 1.7 and 2.3 Breast Cancer Incidence in U.S. By Race and Ethnicity

Source: SEER Cancer Statistics Review, 1975-2017, 2020 [611]

Learn about differences in breast cancer rates in the U.S. and around the world.

Lifetime risk of breast cancer by race and ethnicity

The lifetime risk of breast cancer for women in the U.S. is about 13 percent [3]. However, this risk varies by race and ethnic group.  

Race and ethnicity

Lifetime risk of breast cancer 

White

13%

Black

12%

Asian and Pacific Islander

11%

Hispanic

11%

American Indian and Alaska Native

8%

Source: SEER Cancer Statistics Review, 1975-2017, 2020 [608].

 

Why are there differences in breast cancer rates?

One reason behind differences in breast cancer rates may be that the prevalence rates of some risk factors for breast cancer vary by race and ethnic group [10].

Known risk factors that vary by race and ethnicity include [300-304]:

For example, compared to Hispanic/Latina women, Black and African American women, and non-Hispanic black women, white/non-Hispanic white women are more likely to have children at a later age, to have fewer children and to use menopausal hormone therapy [10,300,302-307]. These factors increase breast cancer risk [10].

Learn more about rates of breast cancer by race and ethnicity.

Black and African American women

Overall, black women have a slightly lower rate of breast cancer compared to white women [611].

However, there are differences by age [607]:

  • Among women younger than 40, black women have higher rates of breast cancer compared to white women.
  • Between ages 60-84, white women have higher rates of breast cancer compared to black women.

The reasons behind this are under study. They may include differences in prevalence rates of some reproductive and lifestyle factors related to breast cancer risk as well as differences in tumor biology [300-308].

Age at diagnosis

Black women tend to be diagnosed at a younger age than white women [609].

The median age at diagnosis for black women is 60, compared to 63 for white women [609].

Triple negative breast cancer (TNBC)

The biology of some breast tumors varies by race and ethnicity. Triple negative breast cancers (TNBC) are more common among Black and African American women than among women of other ethnicities [304,309-311].

Triple negative breast cancers are:

TNBC has a poorer prognosis compared to other subtypes of breast cancer (at least within the first 5 years after diagnosis) [4,304,312-313].

Possible reasons for differences in rates of TNBC

Some lifestyle factors may play a role in the higher rate of TNBC among Black and African American women compared to other women.

Compared to white/non-Hispanic white/Caucasian women, Black and African American women tend to have lower rates of breastfeeding and tend to carry excess weight in the abdomen area [112-113,303,314-315]. Both of these factors may increase the chances of having TNBC [112-113,303,308,314-315].

Certain reproductive and lifestyle factors may also protect more against estrogen receptor-positive (ER-positive) breast cancers than ER-negative breast cancers, including TNBC.

Black and African American women may be more likely than white women to have these protective factors, but they may not lower the risk of TNBC as much as they lower the risk of ER-positive cancers.

For example, Black and African American women are more likely than white/non-Hispanic white/Caucasian women to [112,303,314-315]:

  • Have more children
  • Be a younger age at first childbirth
  • Be overweight or obese before menopause

Although these factors lower the risk of breast cancer, this benefit may be limited to ER-positive breast cancers [67-68,112,303,314]. There’s even some evidence these factors may increase the risk of TNBC [67-68,112,303,314].

These topics are under study.

Learn more about the molecular subtypes of breast cancer.

Learn more about rates of breast cancer by race and ethnicity.