What is the risk of breast cancer for African American Women?
Breast cancer is the most commonly diagnosed cancer among African American women. An estimated 19,540 new cases of breast cancer are expected to occur among African American women in 2009. The overall incidence rate of breast cancer is 10% lower in African American women than in white women. Among younger women (under age 40), however, the incidence is higher in African Americans than in whites. 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 1995-2005, while rates decreased by 0.7% per year among women under age 50 from 1991-2005. At this time, there is no guaranteed way to prevent breast cancer, which is why regular mammograms are so important. A woman’s best overall preventive health strategy is to reduce her known risk factors as much as possible by avoiding weight gain and obesity, engaging in regular physical activity, and minimizing alcohol intake. Women should consider the increased risk of breast cancer associated with menopausal hormone therapy (MHT) use when evaluating treatment options for menopausal symptoms. More information about breast cancer is available in the American Cancer Society publication Breast Cancer Facts & Figures, available online at www.cancer.org.
Breast cancer is the second most common cause of cancer death among African American women, surpassed only by lung cancer. An estimated 6,020 deaths from breast cancer are expected to occur among African American women in 2009. 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 (1.9% per year) than in women aged 50 and older (1.2%). 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, the decrease in breast cancer death rates has been smaller in African American than white women.
During the early 1980s, breast cancer death rates for white and African American women were approximately equal, yet in the period 2001-2005, African American women had a 37% higher death rate than white women. This difference accounts for more than one-third (37%) of the overall cancer mortality disparity between African American and white women. The higher breast cancer mortality rate among African American women compared to white women occurs despite a lower incidence rate. Factors that contribute to the higher death rates among African American women include differences in access to and utilization of early detection and treatment and differences in tumor characteristics.
The 5-year relative survival rate for breast cancer diagnosed in 1996-2004 among African American women was 77%, compared to 90% among whites. 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 diagnosed at a local stage, compared to 62% among white women. Within each stage, 5-year survival is also lower among African American women.
Studies have documented 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. Thomson and colleagues, studying an all white Scottish population, suggest that poor women with breast cancers are more likely to be diagnosed with estrogen receptor-negative tumors. Poverty likely influences disease pathology and genetic markers of disease through lifelong dietary and reproductive habits.