The incidence of breast cancer in the United States has been relatively stable since 2002 after many decades of steady increase.1 Nevertheless, it remains the second most common cancer among U.S. women, after cancers of the skin.2 More than 3 million women are living with breast cancer, according to recent estimates.3
Overall, U.S. women today have about a 1 in 8 chance of developing breast cancer at some point during their lives, although both incidence and mortality rates vary by race and ethnicity (see Special Population, below).4 Breast cancer accounts for approximately 29% of U.S. cancer cases newly diagnosed in women annually.5
In 2017, an estimated 252,710 new cases of invasive breast cancer and 63,410 cases of breast carcinoma in situ will be diagnosed in U.S. women.6 This translates to about 125 new cases per 100,000 women per year.3
The most commonly diagnosed breast cancer is invasive ductal carcinoma, also called infiltrating ductal carcinoma, or IDC. About 80% of invasive breast cancers fall in this category.7
Most breast cancers are diagnosed at a local stage (they have not spread beyond the breast).1
Breast cancer incidence increases with age, and 61 years is the most recently reported median age at the time of breast cancer diagnosis.5 (This means that half of women who developed breast cancer were 61 years of age or younger.)
Eighty percent of new, invasive breast cancer cases occurred in women 50 years and older. To break this down, 4.5% of new invasive cases in 2015 were in women under 40 years, 15.5% were in women ages 40-49, 23% in women ages 50-59 years, and 25.9% in women ages 60-69 years. After that, the incidence by decade declines to 18.3% in women ages 70-79 and 12.5% in women ages 80 and older.5
Mortality and Survival
An estimated 40,610 U.S. women will die from breast cancer in 2017, which equals about 21.5 deaths per 100,000 women per year (age adjusted).3,6 These death rates dropped from 1989 to 2014 by 38% percent, from 33.2 per 100,000 women in 1989 (age adjusted to the 2000 US standard population) to 20.5 per 100,000 women in 2014.8 Only lung cancer kills more women each year.2
Factors contributing to mortality decreases may include finding breast cancer earlier through screening and increased awareness and significant improvements and innovations in treatment.2 Since 2007, breast cancer mortality has continued to decrease in older women, and has been steady in women under 50 years.2
Two principle biomarkers examined in breast cancer tumors are the presence of hormone receptors (estrogen and progesterone) and a gene mutation that leads to the overexpression of HER2 proteins (human epidermal growth factor receptor 2).5 Testing for these biomarkers helps project treatment responses and outcomes, as therapies have been developed for breast cancers with hormone receptor positive and HER2-positive biomarkers. Recent findings show that approximately:5
74% of breast cancers are hormone receptor-positive/HER2-negative
12% are triple negative (i.e., hormone receptor-negative/HER2-negative)
10% are hormone receptor-positive/HER2-positive
4% are hormone receptor-negative/HER2-positive
The percentage of five-year relative survival for women diagnosed with breast cancer is approximately 90%, including all stages combined.3 In other words, women diagnosed with breast cancer are 90% as likely as women in the general population to live five years beyond their diagnosis. Survival rates are averages, however, and many factors may play a role for individual women. The five-year relative survival rates by overall stage are as follows:4
The overall breast cancer incidence rate in California was lower compared to the rest of the nation from 2008-2012, including in every race/ethnicity bracket, as measured by the Surveillance, Epidemiology, and End Results (SEER) program.9
More women in California are living with breast cancer than any other type of cancer (other than cancers of the skin), totaling 341,000 existing cases and accounting for 43% of all cancers in women in 2013. Breast cancer accounts for 32% of California's new cancer cases in women, 25,632 new cases in 2013.9
The incidence of female breast cancer in California has decreased by 8% from 1988 to 2013. Breast cancer mortality declined in California declined during the same period by 36%, roughly similar to the overall decline in the United States.9
Special U.S. Population: Breast Cancer in African American/Black Women
Diagnosis, Prognosis, and Mortality
A striking disparity in the U.S. is the way breast cancer affects African American/Black women compared to women from other racial ethnic groups. Although incidence rates of breast cancer for Black and White women converged in 2012, Black women are more likely to be diagnosed at a young age.10 In addition, the prognosis for Black women with breast cancer is worse than for other women. Black women are far more likely to die of breast cancer than women belonging to other racial/ethnic groups.10
Age at Diagnosis
Between the ages of 60 and 84, breast cancer incidence rates are higher in White women than Black women. However, Black women have a higher incidence rate before the age of 45 and are more than twice as likely to be diagnosed with breast cancer before the age of 35 than other women.11-19 The median age of breast cancer diagnosis is age 58 for Black women and age 62 for White women.10
In general, Black women are more likely to have a poorer prognosis than women of other races/ethnicities, with higher rates of:
Breast cancer diagnosed at advanced stages;1,10,11,14,15,17,20-25
Lymph node involvement at diagnosis;11,14,20
Triple-negative breast cancers;10,15,19,20,26
One study found that the rate of triple-negative breast cancer in Black women was nearly twice as common as in White women (24.6% among Black women and 10-16.7% for other groups);5,26
Poorly differentiated tumors (higher grade), another indication of poor prognosis.1,14,27
Mortality Rates by Race/Ethnicity per 100,000
American Indian/ Native Alaskan
U.S. 2009-2013, Age-Adjusted
Although mortality rates for breast cancer have been steadily declining, the decline has been much slower for Black women.23 The mortality disparity between Black and White women has increased since the 1980s.
Today, mortality rates for Black women remain higher than for women belonging to any other racial/ethnic groups. (see Table)10,23,28,29 In 2012, the breast cancer mortality rate for Black women was 42% higher than the rate for White women.10 Additionally, Black women die younger than White women, with the age of breast cancer-related death averaging 62 and 69 years for Black and White women respectively.10
This disparity persists for Black women even after accounting for the demographic characteristics, cancer stage, and tumor biology of the patients.14,16,20,21,27,30-32
Explaining the Disparities
Many explanations for racial disparities in breast cancer survival have been explored but the evidence is conflicting. Possible explanations include unequal care, inherent differences in tumor biology, and higher rates of risk factors and comorbidities.
The difference in survival rates between Black and other women is explained partially by differences in screening and treatment. Although overall screening rates between Black and White women are now similar, Black women with breast cancer are less likely to have undergone regular breast cancer screening.22,29 They are also more likely to experience delays in diagnosis after screening.22,33-35
With regard to treatment, Black women more often have delays in the initiation of treatment and more often receive no treatment at all.22,29,33,34,36,37 Black women also more frequently receive treatment that is not the standard of care. For example, studies have shown that they are less likely to undergo radiation therapy after breast conserving surgery and more likely to receive suboptimal chemotherapy regimens.11,22,29,38-41
Evidence is inconsistent about whether the racial disparity in survival between Black and White women remains when women receive the same treatment. Some report that while the disparity is reduced with equal treatment, Black women continue to have poorer survival than White women do, even when the treatment regimens are equal.11,13,21,22,37 Others have argued that when Black women receive appropriate treatment, differences in mortality rates nearly or entirely disappear.42-45
Differences in tumor biology also contribute to the mortality disparity. Hormone receptor-negative, triple negative, late stage, higher grade, and larger tumors lead to worse outcomes, and the greater proportion of these tumor characteristics in Black women may partly explain survival differences.22,27 Studies fairly consistently show, however, that when comparing Black women and women of other race/ethnicities with the same tumor characteristics, the mortality rate continues to be higher for Black women.14,16,20,21,27,31,32
Risk for breast cancer is modulated by certain factors. For example, post-menopausal obese women are at greater risk than non-obese women, and women who breast feed are at lower risk than those who do not. Some research has suggested, therefore, that Black women have a greater number of risk factors for breast cancer than other women and these differences contribute to disparities in breast cancer mortality. However, even when these factors are controlled for, Black women are more likely to die from breast cancer.
Obesity and breast feeding
The prevalence of obesity is much higher in Black women, while the frequency and duration of breast feeding is lower, and both of these factors contribute to the risk of hormone-receptor negative cancers.17,46,47 Some research suggests that up to 68% of basal-like breast cancers (these are usually triple negative cancers) could be prevented in younger Black women by encouraging them to breastfeed and to reduce abdominal fat.48 Other studies, however, have found little difference in the number of risk factors between Black and White women or have found that the disparity remains even when risk factors such as obesity are accounted for.37,49
Socioeconomic status (SES)
Low socioeconomic status (SES) is a known risk factor for breast cancer mortality.50 In addition, women who are uninsured or who receive their insurance through Medicaid are more likely to be diagnosed with advanced stage disease and have lower survival rates even after adjustment for other factors.51 Because Black women experience poverty at greater rates than White women, some research has argued that race serves as a proxy for SES.42 However, other research indicates that when SES is controlled for, being Black remains an independent predictor of mortality.20,52
Adverse events and stressors
Adverse life events and stressors, particularly during childhood, are known to impact health, and individuals who have experienced more adverse events have higher rates of illness and disease with earlier onset, which may include breast cancer.53-57 For instance, perceived experiences of racism are correlated with an increased rate of breast cancer among young, Black women.55 Black women have been shown to experience greater stress-related biological aging than White women.58 Therefore, Black women may be at a greater risk of breast cancer mortality because they have experienced greater social and emotional adversity, leading to more severe diagnoses and diagnosis at an earlier age.59
Black women may also have a greater rate of comorbidities, including such conditions as diabetes and hypertension, but research findings about the contribution of comorbidities to the survival disparity are inconsistent.22,47 Some research indicates that these conditions explain a large portion of the survival disparity.22 Other studies have found, however, that while the rate of comorbidities is higher among Black women, and this impacts all-cause survival, this higher rate contributes very little to the difference in breast-cancer specific mortality.29,47,60
Reversing Breast Cancer's Disparity Burden
It is likely that all of these factors, in interaction with each other, influence poor outcomes for Black women. Contributors to the mortality gap include:59,61-63
biological factors, such as tumor characteristics;
individual characteristics such as risk factors and comorbidities;
social conditions such as socioeconomic status;
patterns of care, such as time to follow up on abnormal results, treatment delays and inappropriate therapies.
Kohler BA, Sherman RL, Howlader N, et al. Annual report to the nation on the status of cancer, 1975-2011, featuring incidence of breast cancer subtypes by race/ethnicity, poverty, and state. J Natl Cancer Inst. 2015;107(6):djv048.
American Cancer Society. Cancer A-Z: how common is breast cancer. https://www.cancer.org/cancer/breast-cancer/about/how-common-is-breast-cancer.html. Last Revised January 5, 2017. Accessed May 5, 2017.
National Cancer Institute. SEER cancer statistic factsheets: female breast cancer. Bethesda, MD: National Cancer Institute. http://seer.cancer.gov/statfacts/html/breast.html. 2017. Accessed May 15, 2017.
American Cancer Society. Breast cancer detailed guide. Atlanta: American Cancer Society; 2014.
American Cancer Society. Breast cancer facts & figures 2015-2016. Atlanta: American Cancer Society. 2015.
American Cancer Society. Cancer facts & figures 2017. Atlanta: American Cancer Society; 2017.
American Cancer Society. Cancer A-Z: invasive breast cancer. https://www.cancer.org/cancer/breast-cancer/understanding-a-breast-cancer-diagnosis/types-of-breast-cancer/invasive-breast-cancer.html. Last revised August 18, 2016. Accessed May 9, 2017.
American Cancer Society. Cancer statistics center-breast cancer-trends in death rates 1930-2014. https://cancerstatisticscenter.cancer.org/cancer-site/Breast/8eT3p0ns. 2016. Accessed June 8, 2017.
American Cancer Society, California Department of Public Health, California Cancer Registry. California cancer facts & figures 2016. Oakland, CA: American Cancer Society, Inc., California Division; 2016.
DeSantis C, Fedewa SA, Goding Sauer A, Kramer JL, Smith RA, Jemal A. Breast cancer statistics, 2015: convergence of incidence rates between Black and White women. CA Cancer J Clin. 2016;66:31-42.
Joslyn S, West M. Racial differences in breast carcinoma survival. Cancer. 2000;88(1):114-123.
Althuis M, Brogan D, Coates R, et al. Breast cancers among very young premenopausal women (United States). Cancer Causes Control. 2003;14(2):151-160.
Wojcik B, Spinks M, Optenberg S. Breast carcinoma survival analysis for African American and white women in an equal-access health care system. Cancer. 1998;82(7):1310-1318.
Menashe I, Anderson WF, Jatoi I, Rosenberg PS. Underlying causes of the black-white racial disparity in breast cancer mortality: a population-based analysis. J Natl Cancer Inst. 2009;101(14):993-1000.
Amirikia KC, Mills P, Bush J, Newman LA. Higher population-based incidence rates of triple-negative breast cancer among young African-American women: implications for breast cancer screening recommendations. Cancer. 2011;117(12):2747-2753.
Adams SA, Butler WM, Fulton J, et al. Racial disparities in breast cancer mortality in a multiethnic cohort in the Southeast. Cancer. 2012;118(10):2693-2699.
Hall IJ, Moorman PG, Millikan RC, Newman B. Comparative analysis of breast cancer risk factors among African-American women and White women. Am J Epidemiol. 2005;161(1):40-51.
Swanson M, Haslam S, Azzouz F. Breast cancer among young African-American women: a summary of data and literature and of issues discussed during the summit meeting on breast cancer among African American women, Washington, DC, September 8-10, 2000. Cancer. 2003;97(1 Suppl):273-279.
Carey LA, Perou CM, Livasy CA, et al. Race, breast cancer subtypes, and survival in the Carolina Breast Cancer Study. JAMA. 2006;295(21):2492-2502.
Iqbal J, Ginsburg O, Rochon PA, Sun P, Narod SA. Differences in breast cancer stage at diagnosis and cancer-specific survival by race and ethnicity in the United States. JAMA. 2015;313(2):165-173.
Chu KC, Lamar CA, Freeman HP. Racial disparities in breast carcinoma survival rates: seperating factors that affect diagnosis from factors that affect treatment. Cancer. 2003;97(11):2853-2860.
Silber JH, Rosenbaum PR, Clark AS, et al. Characteristics associated with differences in survival among Black and White women with breast cancer. JAMA. 2013;310(4):389-397.
Richardson LC, Henley SJ, Miller JW, Massetti G, Thomas CC. Patterns and trends in age-specific Black-White differences in breast cancer incidence and mortality - United States, 1999-2014. MMWR Morb Mortal Wkly Rep. 2016;65(40):1093-1098.
Ooi SL, Martinez ME, Li CI. Disparities in breast cancer characteristics and outcomes by race/ethnicity. Breast Cancer Res Treat. 2011;127(3):729-738.
Kerlikowske K, Gard CC, Tice JA, et al. Risk factors that increase risk of estrogen receptor-positive and -negative breast cancer. J Natl Cancer Inst. 2017;109(5).
Kurian AW, Fish K, Shema SJ, Clarke CA. Lifetime risks of specific breast cancer subtypes among women in four racial/ethnic groups. Breast Cancer Res. 2010;12(6):R99.
Henson DE, Chu KC, Levine PH. Histologic grade, stage, and survival in breast carcinoma: comparison of African American and Caucasian women. Cancer. 2003;98(5):908-917.
Harper S, Lynch J, Meersman SC, Breen N, Davis WW, Reichman MC. Trends in area-socioeconomic and race-ethnic disparities in breast cancer incidence, stage at diagnosis, screening, mortality, and survival among women ages 50 years and over (1987-2005). Cancer Epidemiol Biomarkers Prev. 2009;18(1):121-131.
Curtis E, Quale C, Haggstrom D, Smith-Bindman R. Racial and ethnic differences in breast cancer survival: how much is explained by screening, tumor severity, biology, treatment, comorbidities, and demographics? Cancer. 2008;112(1):171-180.
Wieder R, Shafiq B, Adam N. African American race is an independent risk factor in survival from initially diagnosed localized breast cancer. J Cancer. 2016;7(12):1587-1598.
Krok-Schoen JL, Fisher JL, Baltic RD, Paskett ED. White-Black differences in cancer incidence, stage at diagnosis, and survival among adults aged 85 years and older in the United States. Cancer Epidemiol Biomarkers Prev. 2016;25(11):1517-1523.
Setiawan VW, Monroe KR, Wilkens LR, Kolonel LN, Pike MC, Henderson BE. Breast cancer risk factors defined by estrogen and progesterone receptor status: the multiethnic cohort study. Am J Epidemiol. 2009;169(10):1251-1259.
Gwyn K, Bondy ML, Cohen DS, et al. Racial differences in diagnosis, treatment, and clinical delays in a population-based study of patients with newly diagnosed breast carcinoma. Cancer. 2004;100(8):1595-1604.
Gorin SS, Heck JE, Cheng B, Smith SJ. Delays in breast cancer diagnosis and treatment by racial/ethnic group. Arch Intern Med. 2006;166(20):2244-2252.
Press R, Carrasquillo O, Sciacca RR, Giardina EG. Racial/ethnic disparities in time to follow-up after an abnormal mammogram. J Womens Health (Larchmt). 2008;17(6):923-930.
Hershman DL, Unger JM, Barlow WE, et al. Treatment quality and outcomes of African American versus white breast cancer patients: retrospective analysis of Southwest Oncology studies S8814/S8897. J Clin Oncol. 2009;27(13):2157-2162.
Bustami RT, Shulkin DB, O'Donnell N, Whitman ED. Variations in time to receiving first surgical treatment for breast cancer as a function of racial/ethnic background: a cohort study. JRSM Open. 2014;5(7):2042533313515863.
Dragun AE, Huang B, Tucker TC, Spanos WJ. Disparities in the application of adjuvant radiotherapy after breast-conserving surgery for early stage breast cancer: impact on overall survival. Cancer. 2011;117(12):2590-2598.
Du Xianglin L, Gor BJ. Racial disparities and trends in radiation therapy after breast-conserving surgery for early-stage breast cancer in women, 1992 to 2002. Ethn Dis. 2007;17(1):122-128.
Griggs JJ, Sorbero ME, Stark AT, Heininger SE, Dick AW. Racial disparity in the dose and dose intensity of breast cancer adjuvant chemotherapy. Breast Cancer Res Treat. 2003;81(1):21-31.
Griggs JJ, Culakova E, Sorbero ME, et al. Social and racial differences in selection of breast cancer adjuvant chemotherapy regimens. J Clin Oncol. 2007;25(18):2522-2527.
Cross CK, Harris J, Recht A. Race, socioeconomic status, and breast carcinoma in the U.S: what have we learned from clinical studies. Cancer. 2002;95(9):1988-1999.
Burri SH, Landry JC, Norton HJ, Davis LW. Black and white patients fare equally well when treated with postlumpectomy radiotherapy. J Nat Med Assoc. 2004;96(7):961-967.
Bach PB, Schrag D, Brawley OW, Galaznik A, Yakren S, Begg CB. Survival of blacks and whites after a cancer diagnosis. JAMA. 2002;287(16):2106-2113.
Wheeler SB, Carpenter WR, Peppercorn J, Schenck AP, Weinberger M, Biddle AK. Structural/organizational characteristics of health services partly explain racial variation in timeliness of radiation therapy among elderly breast cancer patients. Breast Cancer Res Treat. 2012;133(1):333-345.
Ogden CL, Carroll MD, Curtin LR, McDowell MA, Tabak CJ, Flegal KM. Prevalence of overweight and obesity in the United States, 1999-2004. JAMA. 2006;295(13):1549-1555.
Tammemagi CM, Nerenz D, Neslund-Dudas C, Feldkamp C, Nathanson D. Comorbidity and survival disparities among Black and White patients with breast cancer. JAMA. 2005;294(14):1765-1772.
Millikan RC, Newman B, Tse CK, et al. Epidemiology of basal-like breast cancer. Breast Cancer Res Treat. 2008;109(1):123-139.
Brinton LA, Benichou J, Gammon MD, Brogan DR, Coates R, Schoenberg JB. Ethnicity and variation in breast cancer incidence. Int J Cancer. 1997;73(3):349-355.
Sprague BL, Trentham-Dietz A, Gangnon RE, et al. Socioeconomic status and survival after an invasive breast cancer diagnosis. Cancer. 2011;117(7):1542-1551.
Shi R, Taylor H, McLarty J, Liu L, Mills G, Burton G. Effects of payer status on breast cancer survival: a retrospective study. BMC Cancer. 2015;15:211.
Newman LA, Griffith KA, Jatoi I, Simon MS, Crowe JP, Colditz GA. Meta-analysis of survival in African American and White American patients with breast cancer: ethnicity compared with socioeconomic status. J Clin Oncol. 2006;24(9):1342-1349.
Monnat SM, Chandler RF. Long term physical health consequences of adverse childhood experiences. Sociol Q. 2015;56(4):723-752.
Gruenewald TL, Karlamangla AS, Hu P, et al. History of socioeconomic disadvantage and allostatic load in later life. Soc Sci Med. 2012;74(1):75-83.
Taylor TR, Williams CD, Makambi KH, et al. Racial discrimination and breast cancer incidence in US Black women: the Black Women's Health Study. Am J Epidemiol. 2007;166(1):46-54.
Kruk J. Self-reported psychological stress and the risk of breast cancer: a case-control study. Stress. 2012;15(2):162-171.
Peled R, Carmil D, Siboni-Samocha O, Shoham-Vardi I. Breast cancer, psychological distress and life events among young women. BMC Cancer. 2008;8:245.
Geronimus AT, Hicken MT, Pearson JA, Seashols SJ, Brown KL, Cruz TD. Do US Black women experience stress-related accelerated biological aging?: A novel theory and first population-based test of Black-White differences in telomere length. Hum Nat. 2010;21(1):19-38.
Williams DR, Mohammed SA, Shields AE. Understanding and effectively addressing breast cancer in African American women: Unpacking the social context. Cancer. 2016;122(14):2138-2149.
Eley JW, Hill HA, Chen VW, et al. Racial differences in survival from breast cancer. Results of the National Cancer Institute Black/White Cancer Survival Study. JAMA. 1994;272(12):947-954.
Andaya AA, Enewold L, Horner MJ, Jatoi I, Shriver CD, Zhu K. Socioeconomic disparities and breast cancer hormone receptor status. Cancer Causes Control. 2012;23(6):951-958.
Daly B, Olopade OI. A perfect storm: How tumor biology, genomics, and health care delivery patterns collide to create a racial survival disparity in breast cancer and proposed interventions for change. CA Cancer J Clin. 2015;65(3):221-238.
Danforth DN, Jr. Disparities in breast cancer outcomes between Caucasian and African American women: a model for describing the relationship of biological and nonbiological factors. Breast Cancer Res. 2013;15(3):208.
All external links are provided
as a service to our visitors for information purposes
only. No endorsement is made or implied.
The Breast Cancer Review
is sponsored by the Department of Health Care Services (DHCS), Every Woman Counts (EWC) program, with the goal of providing healthcare
professionals a general reference for breast cancer screening,
diagnosis, and treatment.
The Breast Cancer Review is not an
expression of medical opinion, diagnosis, prognosis or treatment
for any particular patient. It should be used for informational
EWC does not dispense clinical advice
or patient care consultation.
Links to other web resources
are offered as a courtesy; no endorsement is made or implied. While
every care has been taken in their selection, EWC makes no claims
as to the validity, quality, or viability of their content.