[Achievements and Future Directions of the National Colorectal Cancer Screening Program in Korea].

Colorectal cancer (CRC) is one of the most common malignancies worldwide and the second leading cause of cancer-related death. In South Korea, the incidence of CRC has increased alongside rapid socioeconomic development and westernized lifestyles, but it has recently shown a gradual decline, largely due to the National Cancer Screening Program (NCSP). The NCSP, first launched in 1999 and expanded in 2004 to include CRC screening, has reduced the incidence and mortality of colorectal cancer significantly, while improving the five-year relative survival rate. The Korean Colonoscopy Screening Pilot Study (K-COSPI) reported the feasibility, safety, and high acceptability of colonoscopy as a primary screening tool, suggesting the potential to transition to colonoscopy-based national screening. Nevertheless, challenges persist in increasing participation and maintaining high-quality performance because the adenoma detection rate remains a critical indicator of screening effectiveness. Continuous efforts to strengthen public awareness, enhance the quality control of colonoscopy, and develop evidence-based, risk-stratified screening strategies will be essential for sustaining and advancing this exemplary public health achievement.