OnCo
ideasIdea

Offer the blood test for bowel cancer only to people who refuse stool tests or colonoscopy

Blood tests for bowel cancer miss most precancerous polyps, so they should not replace stool tests. But for the third of people who never do any screening, a blood test may beat nothing.

Shield (Guardant) is FDA-approved with about 83% sensitivity for colorectal cancer but around 13% for advanced adenomas; the concern is substitution away from FIT and colonoscopy. Propose a randomised trial in persistent non-responders: blood test offer versus repeat FIT offer, endpoint stage I-II cancers detected per 1,000 invited.

Hypothesis
Offering a blood test to non-responders raises participation by at least 20 percentage points and yields more early-stage cancers per 1,000 invited than a further FIT invitation.
Rationale
Uptake, not test accuracy, drives population benefit; a moderately sensitive test with high uptake beats an excellent test nobody takes.
What would test it
Run a 20,000-person RCT in a programme with good registry linkage.
Maturity
early clinical
Who has to act
payer
Cost to try
Medium ($1M to $50M)
Years to first evidence
3
Bottlenecks it attacks

Connected

8top

Pages like this

not linked directly; found by shared links