Rates of breast cancer in the U.S. vary by race and ethnicity. White women have the highest incidence (rate of new breast cancer cases) overall, while Asian-American and Pacific Islander women have the lowest (see Figure 2.3 below) [4].
Figure 2.3
|
|
|
Source: American Cancer Society [4] |
Lifetime risk of breast cancer by race and ethnicity
The overall lifetime risk (up to age 80) of breast cancer for women in the U.S. is 12 percent [5,515]. However, this risk varies by race and ethnic group.
|
Race and ethnicity |
Lifetime risk of breast cancer |
|
White |
13% |
|
African-American |
11% |
|
Hispanic (may include other ethnic groups) |
10% |
|
American Indian or Alaska Native |
8% |
|
Asian-American or Pacific Islander |
10% |
|
Adapted from SEER data [5]. |
|
Why are there differences in breast cancer rates?
The main reason seems to be that women from different race and ethnic groups have different prevalence rates of risk factors for breast cancer [6]. Known risk factors that vary by race and ethnicity include [219-222]:
- Age at first period
- Age at menopause
- Age at first childbirth
- Body weight
- Number of childbirths
- Menopausal hormone therapy (postmenopausal hormone use)
For example, compared to Hispanic/Latina women and African-American women, white women are more likely to put off childbirth and to have fewer children, each of which increases the risk of breast cancer [6,219,221,223].
Learn more about rates of breast cancer by race and ethnicity.
- See more at: http://ww5.komen.org/BreastCancer/RaceampEthnicity.html#sthash.2SbG9PAg.dpuf
Asian-American and Pacific Islander women
Breast cancer incidence (new cases) and mortality (death) rates are lower for Among Asian-American and Pacific Islander women than for non-Hispanic white and African-American women [41]. For example, from 2006 to 2010 (most recent data available) [41]:
|
|
Asian-American |
White |
African-American |
|
Incidence |
84.7 per 100,000 |
127.3 per 100,000 |
118.4 per 100,000 |
|
Mortality |
11.5 per 100,000 |
22.7 per 100,000 |
30.8 per 100,000 |
Breast cancer mortality rates vary among different Asian-American and Pacific Islander ethnic groups [55]. However, breast cancer is the second leading causes of cancer death in Asian-American and Pacific Islander women (lung cancer is the major cause of cancer death among these women) [37].
Asian-American and Pacific Islander women have somewhat lower rates of breast cancer screening than African-American and white women [47]. Learn more about breast cancer screening among Asian-American and Pacific Islander women.
See more at:
http://ww5.komen.org/BreastCancer/Statistics.html#ethnicity
http://ww5.komen.org/BreastCancer/RaceampEthnicity.html
Racial & Ethnic Differences - Susan G. Komen for the Cure
Breast cancer: rates of diagnosis and survival 'vary by race'
http://www.medicalnewstoday.com/articles/287992.php
The researchers assessed the biological aggressiveness of small-sized tumors (2 cm or less) across all eight races and ethnicities identified: non-Hispanic white, Hispanic white, black, Chinese, Japanese, South Asian (Asian Indian, Asian Indian or Pakistani, Pakistani), other Asian (Filipino, Thai, Vietnamese, Korean, Kampuchean, Laotian, Hmong) and other ethnicities (including Native American and Alaska Native).
By race/ethnic group, the team also assessed the women's risk of being diagnosed with breast cancer in the early stages of the disease, their likelihood of being diagnosed at a later stage and their risk of death from the disease.
Japanese women more likely to be diagnosed with early-stage breast cancer
The results of the analysis revealed that Japanese women were much more likely to be diagnosed with breast cancer at stage I than non-Hispanic white women; 56.1% of Japanese women were diagnosed at stage I, compared with 50.8% of non-Hispanic white women.
Around 37% of black women and 40.4% of South Asian women were diagnosed with breast cancer at stage I, meaning they were more likely to be diagnosed with the disease at a later stage than non-Hispanic white women.
The risk of death from stage I breast cancer in the 7 years after diagnosis was higher among black women than both non-Hispanic white women and South Asian women, with 6.2%, 3% and 1.7% dying from the condition, respectively.
In addition, the researchers found that black women were much more likely to die from small-sized breast cancer tumors than non-Hispanic white women, at 9% compared with 4.6%.
They say the differences in diagnosis and survival of stage I breast cancer among race/ethnic groups may be explained by variations in biological variations in tumors, including lymph node metastasis, distant metastasis and triple-negative behavior (in which cancer growth is not driven by estrogen receptors, progesterone receptors and human epidermal growth factor receptor 2 (HER2).
The team explains:
"In support of this hypothesis, a black woman with small-sized breast cancer tumors was more likely to present with lymph node metastases, was more likely to have triple-negative cancer and was more likely to present with distant metastases than a non-Hispanic white woman with tumors of similar size."
The researchers note, however, that socioeconomic status, access to and use of health care, adherence to treatment and presence of additional health conditions may have also contributed to variations in diagnosis and survival of early-stage breast cancer.
The team notes several limitations to their study. For example, the SEER data used for the research only represents 28% of the US population, so the results may not be generalizable to all women of different race/ethnic groups in the US.
In addition, they point out that the women in the study may have been subject to different treatments and had various other illnesses, which may have influenced the results. Data on this information, however, was not available.
Breast and ovarian cancer are somewhat more common among women of Ashkenazi Jewish descent (women with ancestors from Central or Eastern Europe). This is likely due to the high prevalence of BRCA1 and BRCA2 (Breast Cancer 1 and 2) gene mutations in these women. Everyone has BRCA1 and BRCA2 genes, but those who have an inherited mutation in either of these genes are at higher risk for breast and ovarian cancer [48-52].
Like other gene mutations, BRCA1 and BRCA2 mutations are rare in the general population. However, between eight and 10 percent of Ashkenazi Jewish women carry one of these mutations [48,53-54].
Learn more about BRCA1 and BRCA2 mutations and breast cancer risk.
Learn about genetic testing for BRCA1 and BRCA2 mutations.
Breast cancer incidence (new cases) and mortality (death) rates are lower for Among Asian-American and Pacific Islander women than for non-Hispanic white and African-American women [41]. For example, from 2006 to 2010 (most recent data available) [41]:
|
Asian-American |
White |
African-American |
|
|
Incidence |
84.7 per 100,000 |
127.3 per 100,000 |
118.4 per 100,000 |
|
Mortality |
11.5 per 100,000 |
22.7 per 100,000 |
30.8 per 100,000 |
Breast cancer mortality rates vary among different Asian-American and Pacific Islander ethnic groups [55]. However, breast cancer is the second leading causes of cancer death in Asian-American and Pacific Islander women (lung cancer is the major cause of cancer death among these women) [37].
Asian-American and Pacific Islander women have somewhat lower rates of breast cancer screening than African-American and white women [47]. Learn more about breast cancer screening among Asian-American and Pacific Islander women.
Breast and ovarian cancer are somewhat more common among women of Ashkenazi Jewish descent (women with ancestors from Central or Eastern Europe). This is likely due to the high prevalence of BRCA1 and BRCA2 (Breast Cancer 1 and 2) gene mutations in these women. Everyone has BRCA1 and BRCA2 genes, but those who have an inherited mutation in either of these genes are at higher risk for breast and ovarian cancer [48-52].
Like other gene mutations, BRCA1 and BRCA2 mutations are rare in the general population. However, between eight and 10 percent of Ashkenazi Jewish women carry one of these mutations [48,53-54].
Learn more about BRCA1 and BRCA2 mutations and breast cancer risk.
Learn about genetic testing for BRCA1 and BRCA2 mutations.
Breast cancer incidence (new cases) and mortality (death) rates are lower for Among Asian-American and Pacific Islander women than for non-Hispanic white and African-American women [41]. For example, from 2006 to 2010 (most recent data available) [41]:
|
Asian-American |
White |
African-American |
|
|
Incidence |
84.7 per 100,000 |
127.3 per 100,000 |
118.4 per 100,000 |
|
Mortality |
11.5 per 100,000 |
22.7 per 100,000 |
30.8 per 100,000 |
Breast cancer mortality rates vary among different Asian-American and Pacific Islander ethnic groups [55]. However, breast cancer is the second leading causes of cancer death in Asian-American and Pacific Islander women (lung cancer is the major cause of cancer death among these women) [37].
Asian-American and Pacific Islander women have somewhat lower rates of breast cancer screening than African-American and white women [47]. Learn more about breast cancer screening among Asian-American and Pacific Islander women.
