Surveillance, Epidemiology, and End Results Data Show Increasing Rates of Distant-Stage Breast Cancer at Presentation in U.S. Women

Background The incidence of distant-stage (metastatic) breast cancer at initial presentation has increased significantly in U.S. women under 40 years of age, but no clear trend in older women has been reported. Purpose To investigate trends in distant-stage breast cancer incidence using the latest available Surveillance, Epidemiology, and End Results (SEER) data, including the COVID-19 pandemic years 2020 and 2021. Materials and Methods In this retrospective study of 71 million to 80 million women annually, SEER 22 stage-specific breast cancer incidence rates from January 2004 to December 2021 were analyzed using Joinpoint software to evaluate trends in distant-stage disease in U.S. women overall, by age group, and by race and ethnicity. Results Distant-stage breast cancer incidence rates at presentation increased significantly for U.S. women overall, with an annual percentage change (APC) of 1.16% (95% CI: 0.92, 1.42; <i>P</i> < .001) over 2004-2021. Distant-stage disease increased consistently for women aged 20-39 years (APC, 2.91%; <i>P</i> < .001) and for women aged 75 years or older (APC, 1.44%; <i>P</i> < .001). For women aged 40-74 years, the distant-stage breast cancer incidence rate increased with an APC of 2.10% over 2004-2010 (<i>P</i> = .002) and an APC of 2.73% over 2018-2021 (<i>P</i> = 0.01). The interruption of care in 2020 due to COVID-19 affected distant-stage breast cancer detection, especially for older women from racial and ethnic minority groups. The incidence of distant-stage breast cancer increased over 2004-2021 for Asian women (APC, 2.90%; <i>P</i> < .001), Black women (0.86%; <i>P</i> = .008), and Hispanic women (1.56%; <i>P</i> < .001) and over 2004-2019 for Native American women (3.86%; <i>P</i> = .04). White women showed an increase over 2004-2012 (1.68%; <i>P</i> = .01) but no evidence of a trend over 2012-2021. Distant-stage cancer incidence rates were 55% higher in Black women than White women. Conclusion Distant-stage breast cancer incidence rates at presentation have increased significantly in U.S. women overall; in age groups 20-39 years, 40-74 years, and 75 years or older; and in Asian, Black, Hispanic, and Native American women. © RSNA, 2024 <i>Supplemental material is available for this article.</i> See also the editorial by Kim and Moy in this issue.