The impact of the COVID-19 pandemic on breast cancer stage at time of diagnosis at a major health system in New Jersey.

11142 Background: The COVID-19 pandemic led to strict social distancing protocols in all aspects of daily life creating barriers to healthcare access. This resulted in a decrease in cancer screening, including mammography, which in turn led to higher stage of breast cancer at the time of diagnosis. This is reflected in the current literature 1 . We completed a study at our institution to evaluate the impact of the COVID-19 pandemic on breast cancer screening and stage at diagnosis. Methods: We performed a retrospective chart review of patients aged 18 and older in a large New Jersey health system. IRB approval was obtained. Clinical and pathologic stage at time of breast cancer diagnosis as well as number of screening mammograms ordered and completed in the pre-COVID era (January 1, 2016 – December 31, 2019) and post-COVID era (January 1, 2020 – December 31, 2023) were evaluated. Chi-square hypothesis testing was used for data analysis. Of the 5613 patients identified, 4279 patients had clinical staging data documented. Results: Between 2016-2019, 80.1% of ordered screening mammograms were completed in our health system. As expected, the percentage of completed screening mammograms decreased to 63.7% during the peak of the COVID-19 pandemic from 2020-2021. However, this percentage further decreased to 61.8% between 2022-2023; p-value < 0.001 (Table 1). We also noted an increase in stage 0 and 1 breast cancers and a decline in stage 2-4 breast cancers during these time periods; p-value < 0.001. Conclusions: Our study demonstrates an expected decline in screening mammogram rates during the peak of the COVID-19 pandemic (2020-2021). This can be explained by the uncertainties around health care and social distancing recommendations. Despite participation in a national cancer screening campaign led by the American Cancer Society from May to December 2021, the completion rates of screening mammograms unfortunately continued to decline in the post-COVID years. Contrary to what has been reported, this study found that patients were diagnosed at an earlier stage in the post-COVID era. Our study demonstrates that completion rates of screening mammogram dropped during the COVID-19 pandemic and have not improved in the post-COVID times. We hypothesize that with longer-term studies an increase in late-stage breast cancers may be identified due to missed screening mammograms. 1. Pintican, Roxana et al. “COVID-19 pandemic resulted in more metastatic breast cancer cases at diagnosis.” Scientific reports 15,1 29296. 11 Aug. 2025, doi:10.1038/s41598-025-14582-z. Number and percentage of mammography orders completed and canceled by year. Orders Completed Orders Canceled Total 2016 – 2019 157,50780.1% 39,05419.9% 196,561100% 2020 – 2021 99,57163.7% 56,76636.3% 156,337100% 2022 – 2023 129,72261.8% 80,33038.2% 210,052100% Total 386,80068.7% 176,15031.3% 562,950100%