Female breast cancer is the most commonly diagnosed cancer among nearly every racial and ethnic group in the U.S. However, the past 25 years have seen much improvement in treatment and overall breast cancer care, which have greatly increased survival rates over the years. During this time, overall breast cancer rates have decreased, but have remained stable since 2004. Breast cancer deaths have decreased by as much as 34 percent and continue to decline . These trends indicate real progress. Unfortunately, improvement has not occurred equally among all populations. Many populations within the U.S. continue to be disproportionately burdened by high incidence (new cases) and mortality rates of breast cancer.
These differences lead to, and are often referred to as disparities. They affect how different communities are impacted by breast cancer incidence, mortality and survival. Understanding these differences is critical to reducing breast cancer disparities.
Disparities do not describe all health differences. Disparities are the result of health differences that may arise from inequities such as intentional or unintentional discrimination and/or social disadvantage. They may include, but are not limited to, health differences among populations according to race/ethnicity, ancestry, cultural factors, socioeconomic status, age, sexual orientation, geography, disability or other characteristics associated with social inequality or discrimination .
There are many complex factors that contribute to breast cancer disparities. The most apparent factors are linked to medical care and a lack of health care coverage. However, a person’s health is not just a product of good medical care. Studies show it accounts for only a small percent of disparity related breast cancer deaths. Factors affected by social and racial inequalities such as education, income and the quality of neighborhood environments are thought to play a major role in health disparities [3, 4]. Breast cancer disparities can be affected by:
Even when access to health care services is equal, there are differences in the size, stage and grade of breast cancer for many minority women compared to white women. For example:
While social and biological factors each have their own effects on breast cancer disparities, some social factors may help facilitate or contribute to biological differences or disparities. For example:
Caucasian women have the highest incidence rates of breast cancer in the U.S. followed closely by African American/black women. Comparatively, Asian American (Asian/Pacific Islander as a group), Native American (American Indian/Alaska Native) and Hispanic/Latina women have much lower incidence rates (Figure 1).
1. Although African American and black are often used interchangeably, it should be noted that not all blacks are of African descent and thus African American. The racial category of black includes not only African Americans, but also blacks from other origins or cultures.
2. Although Hispanic and Latina are often used interchangeably and frequently not distinguished from each other in research studies, it should be noted that the groups differ. Hispanic generally refers to language and people of Spanish origin (coming from Spain or speaking Spanish). Latino/a refers to geography, specifically Latin America, the Caribbean and Central America. While there is some overlap between the groups, not all Latinos are Hispanic and vice versa.
Source: U.S. Cancer Statistics Working Group. United States Cancer Statistics: 1999–2010 Incidence and Mortality Web-based Report. Atlanta (GA): U.D. Department of Health and Human Services, Centers for Disease Control and Prevention and National Cancer Institute; 2013. Available at: http://www.cdc.gov/uscs.
However, rates can vary a lot even among individual ethnic or racial subgroups. For example, the racial category of Asian and Pacific Islander includes many smaller ethnic groups that are highly diverse in terms of lifestyles, health care practices, socioeconomic status and other factors that can affect breast cancer rates. In fact, research shows that Asian women do not have uniformly low rates of breast cancer. Filipinas have much higher incidence rates compared with other Asian groups; US-born Asian women have higher incidence rates compared with foreign-born Asian women; and some Pacific Islanders such as Japanese or Hawaiian women have been found to incidence rates higher than Caucasian women [12, 13, 14].
The incidence rates of most diseases are higher among poorer communities. However, the opposite is true of breast cancer. Breast cancer incidence is higher in communities with higher socioeconomic status. This may be because women of higher socioeconomic status get screening mammograms at a higher rate than women of lower socioeconomic status, resulting in more breast cancers being found. Increased incidence could also be due to the differences in risk factors found in women of different education and income levels. For example, compared to women with lower income and education levels, women with higher income and education levels are more likely to:
All of these factors may increase the risk of breast cancer [15, 16, 17].
Lifestyle choices influenced by social and racial inequalities can contribute to breast cancer disparities by affecting a women’s risk of breast cancer. Some risk factors for breast cancer are associated more often with some racial/ethnic groups than others, such as:
Lesbians and bisexual women have a greater risk of breast cancer than other women, but this is not because of their sexual orientation. Rather, it is linked to risk factors for breast cancer that tend to be more common in these women (such as never having children or having them later in life). Lesbians also tend to have higher rates of obesity and alcohol use, both of which can increase breast cancer risk [24, 25].
Having a mutation in the BRCA1/2 gene increases a woman’s risk of developing breast cancer. Though this mutation is rare in the general population, it can occur more commonly in some ethnic groups such as Ashkenazi Jews . Genetic testing, counseling and risk lowering options are available for women with a BRCA mutation. However, some women lack the understanding or resources to seek out or receive such care. Many low-income or underinsured women, as well as underserved minorities, do not have easy access to or seek out BRCA testing or genetic counseling. This can put them at higher risk for being diagnosed with late stage cancer and dying from the disease [27, 28].
Breast cancer screening rates are similar among all racial/ethnic groups, ranging from 69 percent-73 percent (Figure 3) . However, large differences exist for screening rates among different socioeconomic classes, as well as other disparate populations, which may contribute to disparities in breast cancer incidence observed in those groups. Getting screened can detect cancer earlier when chances for survival are highest.
Table 2. Self-Reported Mammogram Prevalence by Education Level
Estimates are adjusted to the 2000 US standard population and reflect mammograms received in the past 2 years, in 2011.
Estimates are adjusted to the 2000 US standard population and reflect mammograms received in the past 2 years, in 2011.
Source: Centers for Disease Control and Prevention Morbidity and Mortality Weekly Report. Cancer Screening- United States, 2010. January 27, 2012/ 61(03);41-45.
Breast cancer stage at diagnosis varies by racial/ethnic and socioeconomic groups. These differences are important because stage at diagnosis impacts a woman’s survival. Research shows that women from minority and medically underserved populations are more likely to be diagnosed with advanced or late-stage breast cancer (has spread beyond the breast). For example:
Women who do not have health insurance are almost four times as likely to be diagnosed with advanced breast cancer compared to women with health insurance .
Research has found that socioeconomic factors and certain attitudes or misconceptions about cancer are associated with delayed or incomplete follow-up of an abnormal screening mammogram. Such attitudes are common among low-income, minority and under- or uninsured populations and are thought to contribute to breast cancer disparities [40, 41, 42]. Waiting longer for follow-up care may lead to cancers that have spread beyond the breast and are harder to treat. For example:
Factors such as race/ethnicity, socioeconomic factors, cultural beliefs, trust in the medical community or differences in medical care can affect the quality and type of breast cancer treatment a woman receives .
Many of the same factors that impact whether a woman gets screened, or how and when she seeks treatment, also impact and contribute to disparities in breast cancer survival.
African American/black women have the highest breast cancer death rates of all racial and ethnic groups and are 41 percent more likely to die of breast cancer than Caucasian women . This disparity is attributed to a number of factors, which include higher rates of early onset, more advanced stage at diagnosis and more aggressive cancer subtypes (TNBC) that occur within this population .
Hispanic/Latina, Asian and Native American women have much lower mortality rates than either African Americans/blacks or Caucasian (Figure 4). However, like breast cancer incidence, mortality rates can differ among individual racial or ethnic subgroups. For example, some Pacific Islander women, such as Hawaiian, not only have higher breast cancer mortality rates compared to other Asian subgroups, but also have higher mortality rate than either blacks or Caucasians.
Figure 4. Female Breast Cancer Mortality by Race, 2006-2010
Source: U.S. Cancer Statistics Working Group.United States Cancer Statistics: 1999–2010 Incidence and Mortality Web-based Report. Atlanta (GA): U.D. Department of Health and Human Services, Centers for Disease Control and Prevention and National Cancer Institute; 2013. Available at: http://www.cdc.gov/uscs.
Women with low income and/or education levels are more likely than women with higher income and/or education levels to die from breast cancer .
Some studies suggest women in a same sex-relationship may have a higher risk of breast cancer death compared to women in a heterosexual relationship .
Women with disabilities have a higher mortality rate than those without a disability. It is not clear whether this disparity is due to differences in treatment choices or because women with disabilities may be more susceptible to treatment-related complications, such as infections and toxicities .
The economic impact of breast cancer disparities is considerable. A report from the C-Change (Collaborating to Conquer Cancer) organization and Susan G. Komen® estimates we can save at least $674 million annually in direct medical costs alone by reducing the disparities in breast cancer access and treatment. This is money spent on the expensive, prolonged therapies that late-stage disease often requires. C-Change estimates at least another $116 million in indirect costs of these disparities in terms of lost wages and productivity .
The Affordable Care Act (ACA) (healthcare reform) is increasing access to health care for many Americans. Since September 2012, all new health insurance plans have been required to cover mammography for women over the age of 40 every one to two years. Starting in 2014, ACA will give access to health coverage for many low-income women who do not currently have insurance through the Insurance Marketplaces and expansion of Medicaid eligibility.
Learn more about the Affordable Care Act.
The Center for Disease Control and Prevention (CDC)’s National Breast and Cervical Cancer Early Detection Program allows each state to provide breast cancer screening to low-income, uninsured and underinsured women. For women who have an abnormal finding, the program also covers diagnostic testing and if breast cancer is diagnosed, referrals for treatment. Women diagnosed through this program can get treatment through expanded Medicaid benefits. (Medicaid is run by each state, so coverage varies state to state).
Learn more about the National Breast and Cervical Cancer Early Detection Program.
Learn more about Medicaid.
Breast cancer takes a disproportionate toll on women of color and those of low-income and education. While unknowns persist regarding the causes of breast cancer disparities and the best ways to reduce and eliminate them, there is much that is clear. According to breast cancer disparities researcher and Komen Scholar, Dr. Rena J. Pasick, “A societal commitment to access to high quality care and to appropriate education for all women stands to alleviate much of the excess burden of this disease. And while more research is needed, it should be based on the recognition that scientific advances can themselves exacerbate disparities in the context of differential availability.”
With 117 Affiliates in local communities and across the globe, Susan G. Komen® is the most progressive grassroots organization fighting breast cancer today. Each year, Komen Affiliates fund thousands of community-based programs that address barriers and needs related to breast cancer. Through community grant programs, education efforts and partnerships, Komen Affiliates are addressing disparities in risk factors that stem from cultural and language differences and societal inequities related to discrimination, provider bias, patient mistrust, poor patient-provider communication, poor adherence and low quality care. These local programs aim to change behaviors and increase access to early detection and quality treatment for disparate populations.
In 2012 alone, Komen Affiliates funded over 1900 grants totaling more than $92 million to local community organizations. These organizations provided millions of services, including mammograms, diagnostic services, educational programs, support services and treatment assistance, to address needs and barriers related to breast cancer disparities.
Komen has also invested approximately $13 million in large-scale vulnerable community grants and national programs that seek to improve quality of care, enhance care coordination, offer financial assistance to breast cancer patients and address unique barriers to breast care for vulnerable populations.
Public policy continues to be a key area of focus at Komen, with sustained advocacy efforts in state capitals across the U.S. and in Washington, D.C. These efforts are focused on protecting breast cancer screening and treatment services, as well as research funding, to advance breast health and cancer care policy at the federal and state levels. It is critical that all women have access to needed breast cancer screenings, life-saving treatment and quality breast cancer care if we are to work to end breast cancer disparities.
Learn more about Komen’s advocacy priorities for 2014
Susan G Komen® has long committed resources and efforts aimed at reducing mortality from breast cancer disparities. Among these efforts, Komen funds hundreds of research grants working to eliminate the burden of breast cancer experienced by all women, including the unequal burden imposed upon women from many minority and medically underserved populations. Since it was founded in 1982, Komen has invested more than $89 million in over 250 research grants that focus on issues related to breast cancer disparities. These grants represent more than 10 percent of Komen’s total research portfolio (over $800 million). More than two-thirds of these grants support clinical trials focused on breast cancer disparities. Komen’s disparities grants also include a dedicated grant mechanism that supports the training of graduate students who are pursuing a research career focused on breast cancer disparities, called the Graduate Training in Disparities Research Grant (GTDR).
Learn more about Komen-funded research, as well as Komen’s overall investment in breast cancer disparities.
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