Identifying the optimal strategy for screening of advanced colorectal neoplasia

Abstract

Background and aim: To guide selection of optimal screening strategies for advanced colorectal neoplasia (ACRN), we evaluated the screening performances of sigmoidoscopy, fecal immunochemical test (FIT), and the Asia-Pacific Colorectal Screening (APCS) system, as well as combinations of these techniques.

Methods: We reviewed the records of participants who had undergone a colonoscopy and FIT as part of a comprehensive health-screening program. Results of sigmoidoscopy were estimated from lesions under colonoscopic examination. The screening strategies were classified as sigmoidoscopy-based, FIT-based, and APCS-based. The sensitivity and reduction of number needed to colonoscope (NNScope) of each screening strategy were assessed.

Results: Of 23 023 participants, 398 (1.7%) had ACRN. To predict the presence of ACRN, sigmoidoscopy was the most effective method (odds ratio [OR]: 22.96, 95% confidence interval [CI]: 18.26-29.07), followed by FIT (OR: 7.18, 95% CI: 5.28-9.68) and APCS (high risk [≥4] OR: 2.59, 95% CI: 1.87-3.58; moderate risk [2-3] OR: 1.66, 95% CI: 1.28-2.17). Regarding sigmoidoscopy-based strategies, "sigmoidoscopy positive alone" and "sigmoidoscopy positive or APCS ≥4" were optimal strategies (reduction of NNScope: 79-86%; sensitivity: 73-78%). In the case of FIT-based strategies, "FIT positive or APCS ≥4" was the optimal strategy (reduction of NNScope: 72%; sensitivity: 37%). With regard to the APCS system only, "APCS ≥2" and "APCS ≥4" were recommended as sensitivity-preferred and reduction in NNScope-preferred strategies, respectively.

Conclusions: The performance in ACRN prediction differs among screening methods (sigmoidoscopy, FIT, and APCS). Among the various single or combined screening strategies, several specific strategies can be chosen depending on medical resources, financial budgets, and screenee preference.

Keywords: Asia-Pacific Colorectal Screening; advanced colorectal neoplasia; colorectal cancer; fecal immunochemical test; screening; sigmoidoscopy.