key: cord-0759249-mle1cbp2
authors: Morrison, David S.
title: Recovering cancer screening in the pandemic: strategies and their impacts
date: 2021-03-15
journal: Br J Cancer
DOI: 10.1038/s41416-021-01264-6
sha: f865130d099906059f25e02a2f7a2665877dee44
doc_id: 759249
cord_uid: mle1cbp2

The coronavirus pandemic has disrupted cancer screening programmes. Kregting and colleagues’ microsimulation models indicate that attempting to quickly catch up with missed screens while simultaneously restarting the ongoing programme would achieve better outcomes but require substantial increases in normal screening capacity that may not be feasible.

restarting them and present their estimated impacts on cancer incidence, mortality and screening capacity. It is worth rehearsing these approaches to restarting screening because doing so in itself is a useful framework for any country considering its options: (1) resume the programme without attempting to catch up on missed screens; (2) postpone the entire programme and advance it wholesale to a later date (at which point the oldest participants would no longer be eligible for screening); (3) resume invitations as normal for those entering the programme for the first time but advance to a later date those already in the programme; (4) postpone the entire programme and advance it wholesale to a later date and continue to screen those who then exceed the maximum age; and (5) resume all screening activity as normal when the disruption ceases and catch-up with those who missed a screen by adding the length of the disruption to their initial invitation date. Broadly, attempting to quickly catch up with missed screens while simultaneously restarting the ongoing programme would require substantial increases in normal screening capacity-perhaps doubling it-while those in which some groups are not pursued might require equal or reduced total capacity. The effects of suspending screening on incidence (that is, observed incidence, not true occurrence) might take 5 years to resolve. Again, in broad terms, attempts to catch up quickly might lead to an initial increase in observed cancer incidence followed by a decrease while the other strategies might lead to a decrease followed by an increase. Early attempts to catch up after the disruption might have little effect on mortality; while the other approaches might increase it for several decades. The impacts of screening disruption on mortality were largest for breast cancer, smaller for colorectal cancer and smallest for cervical cancer.

How can Kregting's results be used to inform cancer screening programme recovery in other countries? Perhaps the starting point is a practical one, by working back from their estimates of required screening capacity. One stark conclusion of this analysis is that only a large increase in screening resources to rapidly catch-up with missed patients will result in minimal effects on cancer mortality. However, as the authors point out, the majority of European countries already had limited resources for screening prior to the pandemic and even usual-let alone greatercapacity will not be restored immediately after pausing screening. This means that there will be a long tail of service disruption until widespread vaccination has effectively eliminated coronavirus from a country. At the time of writing-November 2020-the emergence of several highly efficacious vaccines this month raises www.nature.com/bjc

Received: 1 December 2020 Revised: 4 December 2020 Accepted: 5 January 2021 real hope that many of the restrictions can be lifted at some point in 2021. But even an optimistic assessment would be that cancer screening in many countries will have been disrupted for at least 15 months. Might trade-offs be made between screening programmes so that resources are shifted towards breast cancer and away from cervical screening? Probably not. In practice, the screening, diagnostic and treatment pathways between the three cancers share few common resources. Some of the assumptions about the numbers of deaths that screening might prevent (for breast cancer, about the same number as estimated for the UK, which is three times larger), impacts on inequalities, and age ranges should also be considered by countries applying Kregting's analysis to their own populations.

While the risk and responses to coronavirus are rapidly changing, there is a universal need to rapidly inform recovery of cancer screening as part of the spectrum of cancer control activities. Kregting and colleagues offer both a helpful practical framework of the options together with estimates of the resources that each might require and their impacts of cancer outcomes.

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Effects of cancer screening restart strategies after COVID-19 disruption

David Morrison is sole author.

Ethics approval and consent to participate Not applicable.

Data availability Not applicable.

The author declares no competing interests.