Abstract
OBJECTIVE: To improve the efficacy of colorectal cancer (CRC) screening, decreasing the occurrence of interval cancers is essential. Most interval CRCs develop from fecal immunochemical test (FIT)-negative CRC. This study examined the clinical characteristics of FIT-negative advanced neoplasms (AN) and sessile serrated lesions (SSL), which are main candidate precursors of FIT-negative CRC, and the eligibility criteria for total colonoscopy (TCS) screening following negative FIT. METHODS: Asymptomatic participants in their 50s were divided into two groups. The FIT-negative group underwent TCS following negative FIT, and the TCS-only group underwent TCS without FIT. One endoscopist reviewed the endoscopic images. Plausible risk factors for colorectal polyps were extracted. The clinical features of AN and SSL were compared between the groups. RESULT: Of 2,437 participants, 56.2% were included in the FIT-negative group. No between-group differences were recorded for the prevalence of different colorectal polyp types. By multivariate analysis, a significantly lower adjusted odds ratio (AOR) of AN was shown in women, and significantly higher AORs of AN were found for aging, smoking, and a family history of CRC. The AOR of SSL was higher for smokers. The proportion of AN in the right colon was higher in the FIT-negative group. No between-group differences were recorded for SSL. CONCLUSION: FIT screening was less likely to detect CRC and certain precancerous lesions in the right colon. Combining annual FIT with TCS for the high-risk population based on a scoring system, may detect FIT-negative CRC and colorectal polyps, thus, reducing interval cancer.