The impact of the COVID-19 pandemic on attendance and diagnostic outcomes at Breast Screen Western Sydney, Australia

Background: BreastScreen, Australia’s population screening program, was disrupted by the COVID-19 pandemic. This study examined the pandemic’s effect on attendance and assessment outcome data to inform service planning for the recovery period. Methods: BreastScreen Western Sydney data from ‘pre-COVID’ (2018 and 2019) versus ‘COVID-affected’ years (2020 and 2021) were analyzed. The number of screens, recall rate, sociodemographic data of clients, and imaging and pathological features of malignancies were also analyzed. Results: During the four-year study period, COVID-affected years demonstrated an 18.8% reduction in screening episodes (77 510 vs 95 467, P < 0.001) and a 16.3% reduction in malignancies (512 vs 612, P = 0.49) compared to pre-COVID years. The cancer detection rate (cancers detected per 10 000 screens) remained similar (52.8 vs 52.3 per 10 000 screens for invasive cancer, P = 0.89 and 66.1 vs 64.1 for all malignancies, P = 0.62), and the recall rate was lower (4.2% vs 4.8%, P < 0.001). Younger women and first-time screeners were less likely to attend during COVID-19. There was no significant difference in the proportion of ductal carcinoma in situ (DCIS) vs invasive cancers (20.1% vs 18.5%, P = 0.48), the mean invasive tumor size (18.7 mm vs 17.8 mm, P = 0.37), or the size of DCIS (46.4 mm vs 21.8 mm, P = 0.11) between COVID-affected and pre-COVID years. Conclusion: There was an expected reduction in the number of screens and cancers detected during COVID-19, without a change in tumor size or cancer detection rate. Younger women should be targeted for catch-up screening. Services should plan for the 19% of the screening cohort that failed to attend during the pandemic, as they may present with later-stage cancers.