Application analysis of quantitative fecal immunochemical test in opportunistic screening of colorectal cancer / 中华消化杂志

ABSTRACT

Objective:To analyze and evaluate the application of quantitative fecal immunochemical test(FIT) in opportunistic screening of colorectal cancer in asymptomatic population undergoing health checkups.Methods:From January 1, 2018 to December 31, 2021, at the Health Management Center of the First Affiliated Hospital of Soochow University, 53 319 subjects who underwent routine health checkups and with quantitative FIT opportunistic screening for colorectal cancer were selected. Those with positive quantitative FIT results and received colonoscopy were enrolled in the FIT positive group, and those with negative quantitative FIT results and received colonoscopy were enrolled in the FIT negative group. The participation rate and positive rate of quantitative FIT were analyzed. The results of colonoscopy and pathological findings were taken as the gold standard, including normal, non-polyposis lesions, polyposis (hyperplastic and(or) inflammatory polyps, non-advanced adenoma, advanced adenoma), and colorectal cancer, the detection rates of various lesions of the FIT positive and negative groups, the quantitative FIT measurement value of subjects, and the sensitivity and negative predictive value of quantitative FIT for colorectal cancer and advanced adenoma were analyzed. The receiver operating characteristic curve (ROC) was drawn and the area under the curve (AUC) was calculated, the screening efficacy of quantitative FIT for colorectal cancer and advanced adenoma was evaluated. Chi-square test or Fisher exact probability method and Wilcoxon rank sum test were used for statistical analysis.Results:A total of 51 420 cases had completed quantitative FIT, and the total participation rate was 96.44% (51 420/53 319). Quantitative FIT was positive in 2 483 cases (4.83%). The participation rate of colonoscopy in FIT positive group was 26.22% (651/2 483), of which 540 cases were enrolled in FIT positive group. The colonoscopy participation rate of FIT negative group was 1.18% (576/48 937), of which 523 cases were enrolled in the FIT negative group. The detection rates of colorectal cancer and advanced adenoma in FIT positive group were both higher than those of the FIT negative group(3.9%, 21/540 vs. 0, 0/523; 16.1%, 87/540 vs. 3.3%, 17/523), and the differences were statistically significant(Fisher exact probability method and χ2=49.79; both P<0.001). Populations with quantitative FIT values from high to low were those with colorectal cancers, advanced adenomas, non-polyp lesions, non-advanced adenomas, normal, and hyperplastic and (or) inflammatory polyps (1 052.0 ng/mL(390.5 ng/mL, 3 058.0 ng/mL); 294.5 ng/mL (116.8 ng/mL, 951.8 ng/mL); 131.5 ng/mL (10.5 ng/mL, 327.3 ng/mL); 97.0 ng/mL (11.0 ng/mL, 238.0 ng/mL); 20.0 ng/mL (0.0 ng/mL, 175.3 ng/mL); 14.0 ng/mL (0.0 ng/mL, 171.0 ng/mL)), and the difference was statistically significant( H=120.53, P<0.001). The sensitivities(95% confidence interval (95% CI)) of quantitative FIT in colorectal cancer and advanced adenoma were 100.0%(80.8% to 100.0%) and 83.6%(74.8% to 89.9%), respectively. The negative predictive values (95% CI) were 100.0%(99.1% to 100.0%) and 96.7%(94.7% to 98.0%), respectively. The results of ROC analysis showed that the AUCs(95% CI) of quantitative FIT in colorectal cancer and advanced adenoma were 0.874(0.820 to 0.928) and 0.723(0.675 to 0.770), respectively. Conclusions:In this study, the participation rate of quantitative FIT is high. More patients with advanced adenomas and colorectal cancers are found in the high risk popolation with positive quantitative FIT. Quantitative FIT has a good sensitivity and a negative predictive value for colorectal cancer and advanced adenoma. Therefore, positive quantitative FIT-colonoscopies sequential screening should be advocated in population undergoing health checkups for colorectal cancer screening, and it may be applicable to large-scale population screening in China.