{"entity":{"id":"idea-crc-screening-uptake-and-age-extension","kind":"idea","name":"Treat screening uptake, not test sensitivity, as the thing to optimise, and settle the age extension with a trial rather than a model","aka":[],"tldr":"The only randomised trial of screening colonoscopy cut bowel cancer by 18 percent because only 42 percent of the people invited turned up. A test that is 20 percent more sensitive but is taken by the same people buys far less than an invitation that 20 percent more people accept.","summary":"NordICC randomised invitations rather than procedures, and reported a ten-year colorectal cancer risk of 0.98 against 1.20 percent, a number needed to invite of 455, and no difference in all-cause mortality; 11,843 of 28,220 invited (42.0 percent) attended. Nottingham had already shown the same pattern with a cheaper test: 40.4 percent of the screening group never completed a single kit, and 400 of 893 cancers in that arm presented in non-responders. Kaminski's data add the second half: an endoscopist's adenoma detection rate, not the offer itself, determines whether the colonoscopy that follows a positive test prevents anything.\n\nThe screening age is the other live question. The United States moved to 45 in 2021 on the strength of Siegel's birth-cohort analysis, and 20 percent of United States cases are now in people under 55. No randomised evidence exists for the extension; the decision rested on modelling, and the capacity cost falls on the same endoscopy services that are already the constraint.","asOf":"2026-09-24","links":[{"label":"Bretthauer et al.: NordICC (N Engl J Med 2022)","url":"https://europepmc.org/article/MED/36214590"},{"label":"Kaminski et al.: quality indicators and interval cancer (N Engl J Med 2010)","url":"https://europepmc.org/article/MED/20463339"},{"label":"ClinicalTrials.gov NCT00883792","url":"https://clinicaltrials.gov/study/NCT00883792"}],"tags":["colorectal-evidence"],"related":["colorectal-roadmap","early-detection-roadmap"],"cancers":["colorectal","early-onset-colorectal"],"sections":["early-detection","prevention"],"technologies":["colorectal-screening","colonoscopy","cologuard","liquid-biopsy","ai-endoscopy-detection"],"targets":[],"drugs":[],"companies":[],"institutions":[],"pathways":[],"terms":["fit-test"],"trials":["nordicc"],"people":[],"bottlenecks":["b-early-detection","b-prevention-adoption","b-global-access","b-workforce"],"keyPapers":["paper-bretthauer-nordicc-colonoscopy-screening-nejm-2022","paper-hardcastle-nottingham-faecal-occult-blood-lancet-1996","paper-kaminski-adenoma-detection-rate-interval-cancer-nejm-2010","paper-imperiale-multitarget-stool-dna-screening-nejm-2014","paper-siegel-colorectal-cancer-statistics-ca-2023"],"journals":[],"dependsOn":[],"notes":[],"hypothesis":"Uptake interventions with an established effect in other programmes (general practice endorsement, pre-invitation letters, text reminders, kit design, targeted outreach in the lowest-participation deciles) raise colorectal cancer screening participation by at least 10 percentage points, and deliver a larger reduction in colorectal cancer mortality per pound spent than lowering the starting age by five years.","rationale":"Programme effect is the product of test performance and participation, and participation is the term with the most headroom and the lowest marginal cost. An age extension adds the least dense part of the risk distribution to a service whose binding constraint is colonoscopy capacity.","test":"A cluster-randomised trial within a national programme comparing an uptake bundle against usual invitation, with participation at one round as the primary outcome and stage distribution and colorectal cancer mortality as long-term outcomes; alongside it, a stepped-wedge rollout of the age extension by region, so the incremental yield, the colonoscopy demand and the interval cancer rate are measured rather than modelled.","maturity":"being-tested-at-scale","actor":"policy","cost":"large","horizonYears":6},"route":"/ideas/idea-crc-screening-uptake-and-age-extension/","neighbours":{"roadmap":[{"id":"colorectal-roadmap","kind":"roadmap","name":"Colorectal cancer roadmap: from the adenoma-carcinoma sequence and the first screening trials to total mesorectal excision, oxaliplatin, RAS testing, immunotherapy for mismatch repair-deficient disease, ctDNA-guided treatment and organ preservation","route":"/roadmaps/colorectal-roadmap/"},{"id":"early-detection-roadmap","kind":"roadmap","name":"Early detection roadmap: organ screening → blood tests for many cancers","route":"/roadmaps/early-detection-roadmap/"}],"cancer":[{"id":"colorectal","kind":"cancer","name":"Colorectal cancer","route":"/cancers/colorectal/"},{"id":"early-onset-colorectal","kind":"cancer","name":"Early-onset colorectal cancer (under 50)","route":"/cancers/early-onset-colorectal/"}],"section":[{"id":"early-detection","kind":"section","name":"Early Detection & Screening","route":"/fronts/early-detection/"},{"id":"prevention","kind":"section","name":"Prevention & Risk","route":"/fronts/prevention/"}],"technology":[{"id":"ai-endoscopy-detection","kind":"technology","name":"AI polyp detection in colonoscopy","route":"/technologies/ai-endoscopy-detection/"},{"id":"colorectal-screening","kind":"technology","name":"Colorectal cancer screening (colonoscopy, FIT, stool DNA, blood)","route":"/technologies/colorectal-screening/"},{"id":"liquid-biopsy","kind":"technology","name":"Liquid biopsy (ctDNA)","route":"/technologies/liquid-biopsy/"}],"term":[{"id":"colonoscopy","kind":"term","name":"Colonoscopy","route":"/terms/colonoscopy/"},{"id":"fit-test","kind":"term","name":"Faecal immunochemical test (FIT)","route":"/terms/fit-test/"}],"drug":[{"id":"cologuard","kind":"drug","name":"Cologuard","route":"/drugs/cologuard/"}],"trial":[{"id":"nordicc","kind":"trial","name":"NordICC (Nordic-European Initiative on Colorectal Cancer)","route":"/trials/nordicc/"}],"bottleneck":[{"id":"b-global-access","kind":"bottleneck","name":"Most of the world has almost no cancer care","route":"/bottlenecks/b-global-access/"},{"id":"b-workforce","kind":"bottleneck","name":"Not enough oncologists, nurses, pathologists, physicists","route":"/bottlenecks/b-workforce/"},{"id":"b-prevention-adoption","kind":"bottleneck","name":"Prevention we already have is not deployed","route":"/bottlenecks/b-prevention-adoption/"},{"id":"b-early-detection","kind":"bottleneck","name":"The hardest cancers are found late","route":"/bottlenecks/b-early-detection/"}],"paper":[{"id":"paper-siegel-colorectal-cancer-statistics-ca-2023","kind":"paper","name":"Colorectal cancer statistics, 2023","route":"/key-papers/paper-siegel-colorectal-cancer-statistics-ca-2023/"},{"id":"paper-bretthauer-nordicc-colonoscopy-screening-nejm-2022","kind":"paper","name":"Effect of colonoscopy screening on risks of colorectal cancer and related death (NordICC)","route":"/key-papers/paper-bretthauer-nordicc-colonoscopy-screening-nejm-2022/"},{"id":"paper-imperiale-multitarget-stool-dna-screening-nejm-2014","kind":"paper","name":"Multitarget stool DNA testing for colorectal-cancer screening","route":"/key-papers/paper-imperiale-multitarget-stool-dna-screening-nejm-2014/"},{"id":"paper-kaminski-adenoma-detection-rate-interval-cancer-nejm-2010","kind":"paper","name":"Quality indicators for colonoscopy and the risk of interval cancer","route":"/key-papers/paper-kaminski-adenoma-detection-rate-interval-cancer-nejm-2010/"},{"id":"paper-hardcastle-nottingham-faecal-occult-blood-lancet-1996","kind":"paper","name":"Randomised controlled trial of faecal-occult-blood screening for colorectal cancer (Nottingham)","route":"/key-papers/paper-hardcastle-nottingham-faecal-occult-blood-lancet-1996/"}]}}