[Comparative study of hypersensitive quantitative fecal immunochemical test and qualitative fecal occult blood test for colorectal cancer and advanced adenoma].

ABSTRACT

Objective: To evaluate the screening performance of hypersensitive quantitative fecal immunochemical test (hs-qFIT) and qualitative fecal occult blood test (FOBT) for colorectal cancer and advanced adenoma. Methods: Consecutive participants scheduled to undergo colonoscopy from April 2020 to April 2021 in Qilu Hospital of Shandong University were included in the study. All the participants were 50-75 years old and at moderate to high risk for colorectal cancer. Participants completed hs-qFIT and two kinds of qualitative FOBTs (colloidal gold method and chemical-immunization method) before colonoscopy. The sensitivities and specificities of hs-qFIT and two qualitative FOBTs for colorectal cancer and advanced adenoma were compared. Results: A total of 910 participants were enrolled in the study, including 451 males and 459 females, aged (59.6±6.4) years. There were 22 cases (2.4%) of colorectal cancer, 61 cases (6.7%) of advanced adenoma, 276 cases (30.3%) of non-advanced adenoma, 194 cases (21.3%) of non-adenomatous polyp, 85 cases (9.3%) of other colorectal lesion and 272 cases (29.9%) of non-colorectal lesion. The sensitivities of hs-qFIT for detecting colorectal cancer increased from 72.7% (95%CI 49.6%-88.4%) to 100% (95%CI 81.5%-100%) with cut-off value decreasing from 200 ng/ml to 10 ng/ml, and the sensitivities of both colloidal gold method and chemical-immunization method were 63.6% (95%CI 40.8%-82.0%) (P=0.008). The detection stability of hs-qFIT for colorectal cancer was higher than colloidal gold method (P=0.016) and chemical-immunization method (P=0.031). The sensitivity for detecting advanced adenoma of hs-qFIT at 10 ng/ml was 52.5% (95%CI 39.4%-65.2%), which was significantly higher than that of colloidal gold method (13.1%, 95%CI 6.2%-24.8%, P<0.001) and chemical-immunization method (6.6%, 95%CI 2.1%-16.7%, P<0.001). Conclusions: The sensitivity and detection stability of hs-qFIT for detecting colorectal cancer was higher than qualitative FOBT. Moreover, the sensitivity for detecting advanced adenoma can be further improved using a lower cut-off value.