Racial and Socioeconomic Disparities in Breast Cancer Diagnostic Work Up and Outcomes

Project Summary U.S. women of minority race/ethnicity, lower education, lower income, rural residence, and the underinsured experience higher breast cancer disease burden and lower survival rates than women without these characteristics, despite recent improvements in screening access and treatments. The majority of efforts to

mitigate these disparities have focused on screening mammography access, but women must navigate multiple additional steps when cancer is suspected, including more imaging, biopsies, and specialist consultations. Each year, >12 million U.S. women enter this diagnostic care continuum. Failure to receive

timely, quality evaluation leads to delayed diagnosis, more invasive procedures, advanced cancer stage at diagnosis, and greater mortality. Compared to screening, surprisingly little is known about disparities during this diagnostic period. It is estimated that up to 30% of women with abnormalities detected by mammography

fail to obtain appropriate or timely follow-up, and up to 50% of racial/ethnic minorities and socioeconomically disadvantaged women experience such failures. A clearer understanding of disparities along the diagnostic continuum is hindered by the decentralized nature of breast cancer screening and diagnosis in the U.S., with

disparities in care likely due to a complex combination of individual, residential, and healthcare delivery factors. We propose to conduct the largest U.S. observational study of disparities in diagnostic breast imaging to date. Specifically, we aim to 1) identify specific subpopulations of women with lower access to and use of key

diagnostic imaging technologies; 2) determine differences in diagnostic outcomes that can serve as quality of care indicators based on race/ethnicity and socioeconomic status; and 3) identify differences in timeliness of diagnostic evaluation among disparities populations. We will use multi-level statistical modeling and mediation

analyses to account for multifactorial interactions that likely influence inequitable diagnostic care. Our team, the Breast Cancer Surveillance Consortium, consists of national experts in breast cancer epidemiology, biostatistics, health services research, medicine, and radiology. The BCSC represents the largest longitudinal

breast cancer imaging data resource linked to long-term outcomes that is representative of the general U.S. population by race/ethnicity. We systematically collect woman-, exam-, residential-, practice-, provider- and tumor-level data across seven regional registries and more than 200 individual practices. With data collected

for 13 million breast imaging exams, 5.5 million of which were performed among traditional disparities populations, our team is well-positioned to carry out the proposed analyses. Our study will help shift the breast cancer disparities research paradigm from focusing on screening access to evaluating the entire diagnostic

episode. By identifying novel quality of care metrics and “early warning” indicators of disparities, our results will inform both practice-level interventions aimed at closing local disparities gaps and national practice guidelines and policies directed towards more equitable breast cancer diagnostic evaluation.