Abstract Background Colorectal cancer (CRC) remains a major public health burden. In 2015, a large-scale population-based CRC screening program was launched in Guangzhou for residents aged 45–74 years. This study assessed the program’s performance during 2015–2023 to inform future strategies. Methods A cross-sectional analysis was conducted by using data from 575,843 first-time participants. High-risk individuals were identified through a risk assessment questionnaire combined with fecal immunochemical test (FIT), with positives referred for colonoscopy. Statistical analyses were weighted according to the 2020 Guangzhou census population. Passive follow-up was performed via the Guangzhou Cancer Registration System, enabling estimation of true positives and false negatives. Group differences were examined by using the χ2 test, and factors associated with participation and lesion detection were analyzed by using multivariate logistic regression models. Results Of 575,843 participants, 83,590 (14.52%; weighted, 14.55%) were assessed as high-risk. Among them, 22,157 (26.51%; weighted, 28.17%) completed colonoscopy. Overall, 915 CRC cases were detected. Higher colonoscopy adherence was associated with higher education, family history of CRC, anorectal symptoms, and financial allowance. Lesions were found to be more common in older individuals, men, and those with positive FIT. More low-risk lesions and fewer early- and mid/late-stage CRCs were found during the second round of screening (2021–2023) than during the first round of screening (2015–2017). Passive follow-up identified 233 CRCs within 1 year among initially screening-negative participants. Conclusions This study demonstrated the feasibility of a two-step CRC screening strategy in Guangzhou and its effectiveness in detecting early lesions. However, poor adherence to follow-up colonoscopy remains a key limitation. Targeted interventions—including health education, system-level support, and appropriate financial incentives—are essential to improve compliance and overall program effectiveness.
Zhao et al. (Tue,) studied this question.