Two Years Post-COVID-19: An Ecologic Study Evaluating the Impact on Brazil's Mammographic Screening Program

The objective of this study was to assess the impact of the COVID-19 pandemic, after 2 years, on mammographic screening in Brazil evaluating BIRADS® results, breast cancer diagnosis rates, and breast cancer stage.

This was an ecological observational study based on retrospective data from Brazil's mammographic screening program from 2015 to 2023.

Data were obtained from the national screening database DATASUS - SISCAN (Cancer System Information) and retrieved in March 2024. Inclusion criteria comprised completeness of mammogram data (incomplete records were excluded), female participants aged 50 to 69 years, and mammograms exclusively performed for screening purposes. The study analyzed the number of mammograms conducted during the specified period, focusing on BIRADS® test results.

Out of 23,851,371 mammograms performed between 2015 and 2023, 15,000,628 were included for analysis. A significant reduction of 39.6% in mammograms was observed in 2020 compared to 2019, followed by a 12.6% decrease in 2021. Notably, a substantial rise in BIRADS categories 4 and 5 examinations was seen post-pandemic. Breast cancer staging analysis revealed a shift towards more advanced stages (III and IV) diagnosed post-pandemic, suggesting potential delays in detection and diagnosis.

In conclusion, the study highlighted significant discrepancies in mammographic screenings and breast cancer diagnosis rates over 9 years. The pandemic reflected significant influence on the timing and stage at diagnosis, suggesting potential delays in detection and diagnosis that resulted in later identification of more advanced disease stages.