Effect of fecal immunochemical test cut-off levels on adenoma detection rate: a systematic review and meta-analysis

Abstract

Background Adenoma detection rate (ADR) is higher after a positive fecal immunochemical test (FIT) compared to direct screening colonoscopy. Objective This meta-analysis evaluated how ADR, the rates of advanced adenoma detection (AADR), colorectal cancer detection (CDR), and sessile serrated lesion detection (SSLDR) are affected by different FIT positivity thresholds. Methods We searched MEDLINE, EMBASE, CINAHL, and EBM Reviews databases for studies reporting ADR, AADR, CDR, and SSLDR according to different FIT cut-off values in asymptomatic average-risk individuals aged 50–74 years old. Data were stratified according to sex, age, time to colonoscopy, publication year, continent, and FIT kit type. Study quality, heterogeneity, and publication bias were assessed. Results Overall, 4280 articles were retrieved and fifty-eight studies were included (277,661 FIT-positive colonoscopies; mean cecal intubation 96.3%; mean age 60.8 years; male 52.1%). Mean ADR was 56.1% (95% CI 53.4 − 58.7%), while mean AADR, CDR, and SSLDR were 27.2% (95% CI 24.4 − 30.1%), 5.3% (95% CI 4.7 − 6.0%), and 3.0% (95% CI 1.7 − 4.6%), respectively. For each 20 μg Hb/g increase in FIT cut-off level, ADR increased by 1.54% (95% CI 0.52 − 2.56%, p < 0.01), AADR by 3.90% (95% CI 2.76 − 5.05%, p < 0.01) and CDR by 1.46% (95% CI 0.66 − 2.24%, p < 0.01). Many detection rates were greater amongst males and Europeans. Conclusions ADRs in FIT-positive colonoscopies are influenced by the adopted FIT positivity threshold, and identified targets, importantly, proved to be higher than most current societal recommendations.