Korean Colorectal Cancer Screening Guidelines for Asymptomatic, average-Risk Adults: The 2025 Revision.

[PURPOSE] To develop the 2025 update to the Korean colorectal cancer (CRC) screening guidelines by systematically assessing recent evidence, integrating domestic data, and addressing changes since the 2015 guideline revision, and accordingly, provide an evidence-based standard for clinicians and policymakers.

[MATERIALS AND METHODS] A multidisciplinary committee developed the guidelines using the Grading of Recommendations, Assessment, Development and Evaluation methodology. The process involved establishing three Key Questions (KQs) focused on efficacy, accuracy, and optimal age and interval for screening. A systematic review of international guidelines and primary literature (327 studies included) was conducted. A utility-based analysis using the Markov model was also performed to determine optimal screening ages and intervals.

[RESULTS] The review identified high-certainty evidence for Fecal Immunochemical Test (FIT) in reducing CRC mortality and moderate-certainty evidence for colonoscopy. Evidence for CT colonography (CTC) and stool DNA testing showed very low certainty. Based on this synthesis and cost-utility analysis, the committee conditionally recommends screening for asymptomatic, average-risk adults aged 45-74 years using either colonoscopy every 10 years or FIT every 1-2 years. CTC and stool DNA testing were not recommended owing to insufficient evidence.

[CONCLUSION] The 2025 Korean Guidelines for Colorectal Cancer Screening provide the latest evidence-based recommendations tailored to the domestic context. By conditionally adopting both colonoscopy and FIT for individuals aged 45-74 years, these guidelines aim to optimize public health outcomes and reduce the colorectal cancer burden in South Korea.