COVID-19 and breast cancer screening in Brazil: a comparative analysis of the pre-pandemic and pandemic periods

Abstract The scope of this study was to evaluate the impacts of COVID-19 on breast cancer screening in Brazil. Data were collected from the Ambulatory Information System relating to “bilateral screening mammography” from January/2015 to December/2021. Analyses were performed by region and for Brazil. The average of exams in each month of the year was calculated based on 2015-2019 data, which was compared, monthly, with the number of exams in 2020 and 2021, obtaining the gross and percentage difference between these values. The same analysis was performed for the total number of exams in 2020 and 2021, individually, and for the two years combined. In 2020 there were reductions in the number of exams, which ranged from 25% (North) to 48% (Northeast), resulting in 1.749 million fewer exams than expected in the country (a drop of 44%). In 2021, the Midwest region presented a number of exams 11% higher than expected, while the other regions presented drops between 17% (North) and 27% (Southeast/South), resulting in 927 thousand exams fewer than expected in Brazil (reduction of 23%). In the joint analysis (2020/2021), reductions varied by region from 11% (Midwest) to 35% (Southeast/South), culminating in 2.676 million exams fewer than expected in Brazil (reduction of 33%).

摘要 本研究旨在评估新型冠状病毒肺炎（COVID-19）对巴西乳腺癌筛查工作的影响。本研究采集了2015年1月至2021年12月期间，门诊信息系统（Ambulatory Information System）中与双侧筛查乳腺X线摄影（bilateral screening mammography）相关的数据集。分析按区域及巴西全国层面展开：基于2015-2019年的数据计算得到年度各月的平均检查量，并将其与2020、2021年各月的检查量进行月度比对，得到两组数值间的绝对差值与百分比差值。此外，研究还分别针对2020年、2021年的总检查量，以及两年合并的总检查量开展了相同的分析。2020年，全国各区域检查量均出现下滑，降幅范围为25%（北部地区）至48%（东北部地区），巴西全国总检查量较预期减少174.9万例，整体降幅达44%。2021年，中西部地区检查量较预期高出11%，其余地区降幅介于17%（北部地区）与27%（东南部/南部地区）之间，巴西全国总检查量较预期减少92.7万例，整体降幅为23%。对2020与2021年进行合并分析后显示，各区域降幅从11%（中西部地区）至35%（东南部/南部地区）不等，巴西全国合计较预期减少267.6万例检查，整体降幅达33%。