Are there racial/ethnic disparities among women younger than 40 undergoing mammography?

While the probability of a woman developing invasive breast cancer at age <40 is low (<1%), mammography use reported among younger women (age <40) is substantial, and varies by race/ethnicity. Little detail is known about mammography use among women aged <40, particularly by race/ethnicity. We describe racial/ethnic differences in: (1) mammography indication after considering underlying risk factors (breast symptoms and family history); (2) follow-up recommendations, and (3) mammography outcomes for first mammograms in women aged <40. These 1996-2005 Breast Cancer Surveillance Consortium data are prospectively pooled from seven U.S. mammography registries. Our community-based sample included 99,615 women aged 18-39 who self-reported race/ethnicity and presented for a first mammogram (screening or diagnostic) with no history of breast cancer. Multivariable analyses controlled for registry site, age, family history of breast cancer, symptoms, and exam year. Overall, 73.6% of the women in our sample were seen for a screening mammogram. Following screening mammography, African American (AA) women were more likely than white women to be recommended for additional workup [relative risk (RR): 1.15 (95% CI: 1.07-1.23)]. Following diagnostic mammography, AA [RR: 1.30 (95% CI: 1.17-1.44)] and Asian [RR: 1.44 (95% CI: 1.26-1.64)] women were more likely to be recommended for biopsy, fine-needle aspiration, or surgical consultation. Depending on race/ethnicity, and considering the rate of true positive to total first screening mammograms of younger women, a women has a likelihood of a true positive of 1 in 363-1,122; she has a likelihood of a false positive of 1 in 7-10. This study of community-based practice found racial/ethnic variability in mammography indication, recommendations, and outcomes among women undergoing first mammography before 40. These findings highlight important areas for future research to understand the motivating factors for these practice patterns and the implications of early mammography use.