A randomised comparison of two faecal immunochemical tests in population-based colorectal cancer screening
Mené aux Pays-Bas auprès de 19 291 personnes invitées à un programme de dépistage du cancer colorectal (âge médian : 61 ans), cet essai compare, du point de vue notamment du taux de participation, du taux de détection de lésions cancéreuses et de la valeur prédictive positive, la performance de deux tests immunochimiques de recherche de sang occulte dans les selles
Objective : Colorectal cancer screening programmes are implemented worldwide; many are based on faecal immunochemical testing (FIT). The aim of this study was to evaluate two frequently used FITs on participation, usability, positivity rate and diagnostic yield in population-based FIT screening.
Design : Comparison of two FITs was performed in a fourth round population-based FIT-screening cohort. Randomly selected individuals aged 50–74 were invited for FIT screening and were randomly allocated to receive an OC -Sensor (Eiken, Japan) or faecal occult blood (FOB)-Gold (Sentinel, Italy) test (March–December 2014). A cut-off of 10 µg haemoglobin (Hb)/g faeces (ie, 50 ng Hb/mL buffer for OC-Sensor and 59 ng Hb for FOB-Gold) was used for both FITs.
Results : In total, 19 291 eligible invitees were included (median age 61, IQR 57–67; 48% males): 9669 invitees received OC-Sensor and 9622 FOB-Gold; both tests were returned by 63% of invitees (p=0.96). Tests were non-analysable in 0.7% of participants using OC-Sensor vs 2.0% using FOB-Gold (p<0.001). Positivity rate was 7.9% for OC-Sensor, and 6.5% for FOB-Gold (p=0.002). There was no significant difference in diagnostic yield of advanced neoplasia (1.4% for OC-Sensor vs 1.2% for FOB-Gold; p=0.15) or positive predictive value (PPV; 31% vs 32%; p=0.80). When comparing both tests at the same positivity rate instead of cut-off, they yielded similar PPV and detection rates.
Conclusions : The OC-Sensor and FOB-Gold were equally acceptable to a screening population. However, FOB-Gold was prone to more non-analysable tests. Comparison between FIT brands is usually done at the same Hb stool concentration. Our findings imply that for a fair comparison on diagnostic yield between FIT's positivity rate rather than Hb concentration should be used.
Gut , résumé, 2016