Breast cancer is the most commonly diagnosed cancer among African American women. An estimated 26,840 new cases of breast cancer are expected to occur among African American women in 2011. Breast cancer incidence rates increased rapidly among African American women during the 1980s largely due to increased detection as the use of mammography screening increased. Incidence rates stabilized among African American women aged 50 and older during 1994-2007, while rates decreased by 0.6% per year from 1991-2007 among women under age 50.
Breast cancer is the second most common cause of cancer death among African American women, surpassed only by lung cancer. An estimated 6,040 deaths from breast cancer are expected to occur among African American women in 2011. Breast cancer death rates among African American women increased 1.5% annually from 1975-1992 and declined thereafter. This decrease was larger in women under 50 (2.0% per year) than in women aged 50 and older (1.2% per year).
The steady decline in overall female breast cancer mortality since the early 1990s has been attributed to improvements in both early detection and treatment. However, breast cancer death rates have declined more slowly in African American women compared to white women, which has resulted in a growing disparity. During the early 1980s, breast cancer death rates for white and African American women were similar; yet in the period 2003-2007, African American women had a 39% higher death rate than white women, despite a lower incidence rate. This difference accounts for more than one-third (37%) of the overall cancer mortality disparity between African American and white women. Factors that contribute to higher death rates among African American women include differences in access to and utilization of early detection and treatment, as well as differences in tumor characteristics.
The 5-year relative survival rate for breast cancer diagnosed in 1999-2006 among African American women was 78%, compared to 90% among white women. This difference can be attributed to both later stage at detection and poorer stage-specific survival among African American women. Only about half (51%) of breast cancers diagnosed among African American women are at a local stage, compared to 61% among white women.
Later stage at diagnosis among African American women has been largely attributed to lower frequency of and longer intervals between mammograms, and lack of timely follow-up of suspicious results. Lower stage-specific survival has been explained in part by unequal receipt of prompt, high-quality treatment for African American women compared to white women. There is also evidence that aggressive tumor characteristics are more common in African American than white women. Other studies suggest factors associated with socioeconomic status may influence the biologic behavior of breast cancer.
*American Cancer Society. Breast Cancer Facts & Figures for African Americans 2011-2012. Atlanta: American Cancer Society, Inc.