Breast Cancer Detection Patterns in Year 2 of the COVID-19 Pandemic Highlight Gains and Gaps in Breast Cancer...

The COVID-19 pandemic severely hindered breast cancer (BC) diagnoses. We investigated the impact of COVID-19 on BC diagnoses in the US.

We retrospectively reviewed the 2024 release of the Surveillance, Epidemiology, and End Results database (SEER: 2000-2021) for invasive BC incidences per 100,000 in adult women. Using the SEER Joinpoint software, we modeled BC incidence trends through 2019 and extrapolated expected incidences in 2020-2021. We compared expected and observed incidences and calculated percent differences (PD) and the national deficit in diagnoses.

Observed BC incidence in 2020 was 122.03, while expected incidence was 132.14, yielding a PD of -7.6% [-8.9%, -6.4%]. In 2021, observed BC incidence exceeded projections (3.5% [2.1%, 4.8%]). These translated to a cumulative deficit of 7190 cases [-11,886, -2494] during 2020-2021. Localized and regional BC detection decreased in 2020 and was within (1.4% [-0.9%, 3.7%]) or exceeded (4.1% [4.2%, 4.4%]) projections, respectively, in 2021. Distant disease detection was within projections in 2020 and exceeded projections in 2021 (3.9% [0.6%, 7.2%]). Across most demographic subgroups, detection was low in 2020. In 2021, cases exceeded projections in White women and metropolitan and high education/income counties, were within projections in racial/ethnic minorities and rural and low education/income counties, and were below projections in 85+ year olds and 10%-19.99% foreign-born counties.

BC detection recovered in 2021 compared to the start of the pandemic, but notable disparities persisted. Careful surveillance and study are needed to prevent further gaps in BC detection years after the pandemic.