Evaluation of long-term benefits and cost-effectiveness of nation-wide colorectal cancer screening strategies in China in 2020-2060: a modelling analysis.

Background: Evidence on the long-term benefits and cost-effectiveness of colorectal cancer (CRC) screening strategies in China remains limited. This modelling study aims to address this issue for various CRC screening strategies in China between 2020 and 2060.

Methods: Using a previously developed microsimulation model (MIMIC-CRC) with Chinese epidemiological data, we evaluated four CRC screening strategies targeting population aged 45-74 years: no screening, colonoscopy every 10 years, biennial faecal immunochemical testing (FIT), and a roll-out FIT screening strategy. Screening coverage (invitation) rates from 5% to 100% were analysed. Single-cohort analysis of 100,000 individuals was conducted to estimate the relative cost-effectiveness of each strategy. A multiple-cohort analysis of 100,000 people aged 40+ over 2020-2060 was conducted to project nation-wide long-term benefits and cost-effectiveness.

Findings: In single-cohort analysis, all strategies yielded reductions in CRC incidence and mortality compared to no screening, with colonoscopy outperforming FIT-based strategies at the same invitation rates. In multiple-cohort analysis, among people over 40 years of age in China over 2020-2060, compared to no screening, at invitation rate of 5%, screening by colonoscopy, biennial FIT and roll-out FIT-based approach were estimated to avert 1.2, 0.4, and 0.3 million incident CRCs and 0.2, 0.1, and 0.1 million CRC-related deaths, respectively, compared to no screening (25.4 million incident CRCs and 4.4 million CRC-related deaths), and this preventive effect enlarged as the screening coverage rate increased. At full coverage, colonoscopy achieved the largest reductions (38.2% lower incidence and 43.2% lower mortality) but required the most resources. Biennial FIT and roll-out FIT-based approach screening was slightly less effective but had significant reduced colonoscopy needs (reduction of 83.8% and 85.2%, respectively) and overall cost (reduction of 23.4% and 37.8%, respectively) compared to colonoscopy screening.

Interpretation: Nation-wide implementation of screening would be effective in reducing the burden of CRC in China. Biennial FIT and roll-out FIT-based screening strategies could prevent incident CRC cases and CRC-related deaths with considerably fewer resources than colonoscopy screening. Efforts should be made to increase the screening coverage in China.

Funding: Chinese Academy of Medical Science Innovation Fund for Medical Science (2022-I2M-1-0031); National Natural Science Foundation of China (82173606; 82273726); Beijing Nova Program of Science and Technology (20230484397).