Colorectal Cancer Screening With Repeated Fecal Immunochemical Test Versus Sigmoidoscopy: Baseline Results From a Randomized Trial
Kristin Ranheim Randel, Anna Lisa Schult, Edoardo Botteri, Geir Hoff, Michael Bretthauer, Giske Ursin, Erik Natvig, Paula Berstad, Anita Jørgensen, Per Sandvei, Marie Ek Olsen, Svein Oskar Frigstad, Ole Darre-Næss, Espen R. Norvard, Nils Bolstad, Hartwig Kørner, Arne Wibe, Knut‐Arne Wensaas, Thomas de Lange, Øyvind Holme
Abstract
Background & AimsThe comparative effectiveness of sigmoidoscopy and fecal immunochemical testing (FIT) for colorectal cancer (CRC) screening is unknown.MethodsIndividuals aged 50–74 years living in Southeast Norway were randomly invited between 2012 and 2019 to either once-only flexible sigmoidoscopy or FIT screening every second year. Colonoscopy was recommended after sigmoidoscopy if any polyp of ≥10 mm, ≥3 adenomas, any advanced adenomas, or CRC was found or, subsequent to, FIT >15 μg hemoglobin/g feces. Data for this report were obtained after complete recruitment in both groups and included 2 full FIT rounds and part of the third round. Outcome measures were participation, neoplasia detection, and adverse events. Age-standardized detection rates and age-adjusted odds ratios (ORs) were calculated.ResultsWe included 139,291 individuals: 69,195 randomized to sigmoidoscopy and 70,096 to FIT. The participation rate was 52% for sigmoidoscopy, 58% in the first FIT round, and 68% for 3 cumulative FIT rounds. Compared to sigmoidoscopy, the detection rate for CRC was similar in the first FIT round (0.25% vs 0.27%; OR, 0.92; 95% confidence interval [CI], 0.75–1.13) but higher after 3 FIT rounds (0.49% vs 0.27%; OR, 1.87; 95% CI, 1.54–2.27). Advanced adenoma detection rate was lower in the first FIT round compared to sigmoidoscopy at 1.4% vs 2.4% (OR, 0.57; 95% CI, 0.53–0.62) but higher after 3 cumulative FIT rounds at 2.7% vs 2.4% (OR, 1.14; 95% CI, 1.05–1.23). There were 33 (0.05%) serious adverse events in the sigmoidoscopy group compared to 47 (0.07%) in the FIT group (P = .13).ConclusionsParticipation was higher and more CRC and advanced adenomas were detected with repeated FIT compared to sigmoidoscopy. The risk of perforation and bleeding was comparable. Clinicaltrials.gov, Number: NCT01538550. The comparative effectiveness of sigmoidoscopy and fecal immunochemical testing (FIT) for colorectal cancer (CRC) screening is unknown. Individuals aged 50–74 years living in Southeast Norway were randomly invited between 2012 and 2019 to either once-only flexible sigmoidoscopy or FIT screening every second year. Colonoscopy was recommended after sigmoidoscopy if any polyp of ≥10 mm, ≥3 adenomas, any advanced adenomas, or CRC was found or, subsequent to, FIT >15 μg hemoglobin/g feces. Data for this report were obtained after complete recruitment in both groups and included 2 full FIT rounds and part of the third round. Outcome measures were participation, neoplasia detection, and adverse events. Age-standardized detection rates and age-adjusted odds ratios (ORs) were calculated. We included 139,291 individuals: 69,195 randomized to sigmoidoscopy and 70,096 to FIT. The participation rate was 52% for sigmoidoscopy, 58% in the first FIT round, and 68% for 3 cumulative FIT rounds. Compared to sigmoidoscopy, the detection rate for CRC was similar in the first FIT round (0.25% vs 0.27%; OR, 0.92; 95% confidence interval [CI], 0.75–1.13) but higher after 3 FIT rounds (0.49% vs 0.27%; OR, 1.87; 95% CI, 1.54–2.27). Advanced adenoma detection rate was lower in the first FIT round compared to sigmoidoscopy at 1.4% vs 2.4% (OR, 0.57; 95% CI, 0.53–0.62) but higher after 3 cumulative FIT rounds at 2.7% vs 2.4% (OR, 1.14; 95% CI, 1.05–1.23). There were 33 (0.05%) serious adverse events in the sigmoidoscopy group compared to 47 (0.07%) in the FIT group (P = .13). Participation was higher and more CRC and advanced adenomas were detected with repeated FIT compared to sigmoidoscopy. The risk of perforation and bleeding was comparable. Clinicaltrials.gov, Number: NCT01538550.