Screening with mammography
is generally recognized as effective in reducing morbidity and mortality from breast cancer.1,2
Despite reporting similar mammography use,3
black and Hispanic women continue to be diagnosed at a later stage of breast cancer compared to white women,4
and this later stage is at least partly responsible for the greater breast cancer mortality experienced by black women in the United States when compared to white women.
In Chicago, Illinois, there is a particularly wide racial disparity in breast cancer mortality that has been increasing since the early 1990s.5,6
During this period, breast cancer mortality rates for black women in Chicago have remained fairly stable while the rates for white women have decreased substantially.5
In 2005, the breast cancer mortality rate for black women was 43.2/100,000, and the rate for white women was 21.8/100,000 (age-adjusted rate ratio=1.98). The breast cancer mortality disparity for Hispanic vs. non-Hispanic whites is difficult to evaluate because breast cancer mortality in Hispanics is generally underestimated.
This pattern suggests that black women have not benefited as much as white women have from the technologic advancements made in breast imaging, diagnosis, and treatment over the last two decades. A recently published article suggests that this may be a pattern for several cancers.7
One set of risk factors for the widening disparity in breast cancer mortality might relate to differences in the effectiveness of mammography in the early detection of breast cancer. Factors related to advantages of an academic medical setting, quality of mammogram interpretation, and quality of imaging could impact the extent to which a woman with a screen-detectable breast cancer benefits from the screening process.
The Metropolitan Chicago Breast Cancer Task Force (MCBCTF) was formed in 2007 to respond to the growing breast cancer mortality disparity and consists of advocates, physicians, administrators, researchers, and epidemiologists concerned with improving breast health (www.sinai.org/urban/summit/docs/Task%20Force%20Rpt_Oct%202007_FINAL.pdf
). Because of the growing and uniquely large racial breast cancer mortality disparity in Chicago, we undertook a survey of mammography facilities in part to determine if specific facility attributes generally associated with higher-quality mammography were equally available to non-Hispanic white, non-Hispanic black, and Hispanic women and to women with vs. without private health insurance. Based on the available literature on factors that may impact mammography screening quality, we decided to examine three measures demonstrated to impact the quality of mammography: access to academic medical centers, access to radiologists who specialize in breast imaging, and access to digital mammography. Examples of evidence include:
- Breast radiologists working in academic settings have more opportunities to advance or sustain their level of mammogram interpretation accuracy beyond what is available to their counterparts at nonacademic facilities.8
- Radiologists who specialize in breast imaging are more successful in detecting early stage cancers than are general radiologists.9,10
- Research has found that digital mammography is better than analog (film screen) mammography at detecting cancerous lesions in younger women and women with dense breasts.11,12
There are other mammography facility practice characteristics that could potentially influence the quality of imaging, interpretation, and timeliness but for which evidence is lacking, and these factors are not examined here.