Yield of Different Quantitative Fecal Immunochemical Test Cut-Offs in the Colorectal Cancer Screening Program
[Purpose]To analyze the diagnostic yield of quantitative fecal immunochemical test(FIT)at different cut-offs in colorectal cancer(CRC)screening.[Methods]The sequential screening method was adapted in Jiashan CRC screening program for local residents aged 40~74 years old,which included a quantitative FIT and high-risk factor questionnaire for primary screening and subsequent colonoscopy for the diagnostic screening.Subjects who participated in quantitative FIT were included in this study between September,2021 and August,2023.The positive predictive values(PPVs)for colorectal neoplasms were calculated at the cut-offs of 100,120,140,160,180 and 200 ng/mL of FIT.The Cochran-Armitage trend test was performed to compare the trend of PPVs at different cut-offs.The effects of different starting age and FIT cut-offs on requirement of colonoscopy and advanced neoplasia detection were assessed.[Results]A total of 58 256 individuals completed the quantitative FIT,and 3 106 had fecal hemoglobin concentrations>100 ng/mL,among whom 2 186 underwent colonoscopic examination with a compliance rate of 70.38%.The colonoscopy detected 588 cases of non-advanced adenomas and 355 cases of advanced neoplasms(AN),in-cluding 30 cases of CRC and 325 cases of advanced adenomas.Progressively increasing the cut-off showed a decrease in PPVs of non-advanced adenomas and an increase of AN.The ratio of the rate of reduced requirement of colonoscopy to the missed rate of the progressive lesions was the smallest when the screening start age was 45 years old and the positive FIT threshold was set at 100 ng/mL.[Conclusion]There were significant differences in the diagnostic yield at different cut-offs of FIT.Increasing the cut-offs of FIT will elevate PPVs for the advanced neoplasms.