Colorectal cancer screening by invitations to fecal immunochemical testing (FIT) or colonoscopy
Castells A et al, Lancet. 2025;405(10486):1231-1239
In a large Spanish randomized trial, participation in screening was higher among individuals invited to FIT screening than colonoscopy screening. On the basis of participation observed in this study, a FIT-based program was non-inferior to a colonoscopy-based program in terms of colorectal cancer-related mortality after 10 years.
Background: Colonoscopy and the faecal immunochemical test are accepted strategies for colorectal cancer screening in the average-risk population (i.e., people aged ≥ 50 years without personal or family history of colorectal cancer). The aim of this trial was to compare whether invitation to screening with faecal immunochemical test was non-inferior to colonoscopy in a screening programme.
Methods: COLONPREV was a pragmatic, randomised, controlled, non-inferiority trial done at 15 tertiary hospitals across 8 regions of Spain. Eligible participants were presumptively healthy and aged between 50 years and 69 years without a personal history of colorectal cancer, adenoma or inflammatory bowel disease, family history of hereditary or familial colorectal cancer (i.e., 2 or more first-degree relatives with colorectal cancer or 1 diagnosed before age 60 years), severe comorbidities, or previous colectomy. Participants were randomly assigned (1:1) to one-time colonoscopy or biennial faecal immunochemical test before invitation to screening. The primary endpoint was colorectal cancer mortality at 10 years, assessed in the intention-to-screen population. An absolute difference of less than 0.16 percentage points was required to show non-inferiority.
Findings: Between June 1, 2009, and December 31, 2021, 57,404 individuals were randomly assigned to receive an invitation for colonoscopy (n = 28,708) or the faecal immunochemical test (n = 28,696). The intention-to-screen population consisted of 26,332 individuals in the colonoscopy group and 26,719 in the faecal immunochemical test group. In the intention-to-screen population, participation in any form of screening was 31.8% in the colonoscopy group and 39.9% in the faecal immunochemical test group (risk ratio [RR] = 0.79 [95% confidence interval [CI]: 0.77–0.82]). Faecal immunochemical testing was non-inferior to colonoscopy with regard to the risk of colorectal cancer mortality at 10 years: the risk was 0.22% (55 deaths) in the colonoscopy group and 0.24% (60 deaths) in the faecal immunochemical test group (risk difference -0.02 [95% CI: -0.10 to 0.06]; RR = 0.92 [95% CI: 0.64–1.32]; pnon-inferiority = 0.0005).
Interpretation: Participation in screening was higher among individuals invited to faecal immunochemical test screening than colonoscopy screening. On the basis of participation observed in this study, a faecal immunochemical test-based programme was non-inferior to a colonoscopy-based programme for colorectal cancer-related mortality.