Impact of COVID-19 Related Disruptions to Colorectal Cancer Screening Programs in Three Countries: A Comparative Modelling Study

Abstract

Background: Colorectal cancer (CRC) screening programs worldwide have been disrupted during the COVID-19 pandemic. This study aimed to estimate the impact of hypothetical disruptions to organized CRC screening programs on short- and long-term CRC incidence and mortality in three countries using microsimulation modelling.Methods: Using CRC microsimulation models for Australia (Policy1-Bowel), Canada (OncoSim) and the Netherlands (ASCCA and MISCAN-Colon) participating in the COVID-19 and Cancer Global Modelling Consortium (CCGMC), we simulated a range of scenarios to assess the potential impact of disruptions to screening on CRC incidence and mortality. Modelled scenarios varied by disruption duration (3-, 6- and 12-months), post-disruption participation decreases, and catch-up screening strategy.Findings: Without catch-up screening, CRC deaths could increase by 0·2-0·5%, 0·4-1·0%, and 0·8-2·0% over 2020-2050 among individuals aged 50 years and older in the three modelled countries after 3-, 6-, and 12- month disruptions, respectively, compared to undisrupted screening. A 6-month disruption would result in an estimated 1,964, 1,319, and 676-856 additional CRC deaths in Australia, Canada and the Netherlands, respectively, compared to undisrupted screening. Providing catch-up screening could minimize the impact of the disruption, while a post-disruption decrease in participation could increase CRC deaths by 1·8-3·7% compared to undisrupted screening.Interpretation: Although the relative impact of the modelled CRC screening disruptions due to the COVID-19 pandemic is modest, there is a clear impact on absolute CRC deaths over the period 2020-2050. It is crucial that, if disrupted, screening programs ensure participation rates return to previously observed rates and provide catch-up screening wherever possible, as the impact of any disruption could be considerably larger otherwise.Funding Statement: The secretariat for the COVID-19 and Cancer Global Modelling Consortium (CCGMC) working group 2 is funded through Cancer Council New South Wales.Declaration of Interests: KC: Dr. Canfell reports and is co-principal investigator of an unrelated investigator-initiated trial of cervical screening in Australia (Compass; ACTRN12613001207707 and NCT02328872), which is conducted and funded by the VCS Foundation (VCS), a government-funded health promotion charity. The VCS Foundation received equipment and a funding contribution from Roche Molecular Systems USA. However, neither KC nor her institution on her behalf (Cancer Council NSW) receives direct funding from industry for this trial or any other project. All other authors declare no conflict of interest.