Is the COVID-19 pandemic associated with a decrease in the number of cancer screening tests globally?
In this systematic review and meta-analysis of 39 publications, the screening types analyzed were associated with a significant overall decrease (−46.7%, −44.9%, and −51.8% for breast, colorectal, and cervical cancer screening, respectively) from January to October 2020. This decrease showed a U-shaped trend with a negative peak in April 2020 (−74.3% for mammography and −69.3% for colonoscopy and fecal occult blood test or fecal immunochemical test) and in March 2020 for Papanicolaou test or human papillomavirus test (−78.8%).
COVID-19 pandemic measures were associated with widely reduced cancer screening services, which was possibly associated with delayed cancer diagnosis and increased cancer mortality.
Public health services, including cancer screening tests, have been affected by the onset of the COVID-19 epidemic.
To investigate the pandemic’s association with cancer screening worldwide.
In this systematic review and meta-analysis, databases such as PubMed, ProQuest, and Scopus were searched comprehensively for articles published between January 1, 2020, and December 12, 2021.
Observational studies and articles that reported data from cancer registries that compared the number of screening tests performed before and during the pandemic for breast, cervical, and colorectal cancer were included.
Data Extraction and Synthesis
Two pairs of independent reviewers extracted data from the selected studies. The weighted average of the percentage variation was calculated between the 2 periods to assess the change in the number of cancer screening tests performed during the pandemic. Stratified analysis was performed by geographic area, period, and type of setting. The systematic review and meta-analysis was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guideline.
Main Outcomes and Measures
The main outcome was the weighted average percentage variation in the number of screening tests performed between January and October 2020 compared with the previous period.
The review comprised 39 publications. There was an overall decrease of −46.7% (95% CI, −55.5% to −37.8%) for breast cancer screening, −44.9% (95% CI, −53.8% to −36.1%) for colorectal cancer screening, and −51.8% (95% CI, −64.7% to −38.9%) for cervical cancer screening during the pandemic. For all 3 cancers, a U-shaped temporal trend was identified; for colorectal cancer, a significant decrease was still apparent after May 2020 (in June to October, the decrease was −23.4% [95% CI, −44.4% to −2.4%]). Differences by geographic area and screening setting were also identified.
Conclusions and Relevance
A summary estimate of the downscaling of cancer screening tests since the onset of the COVID-19 pandemic is provided in this systematic review and meta-analysis. This could be associated with an increase in the number of avoidable cancer deaths. Effective interventions are required to restore the capacity of screening services to the prepandemic level.