Cost-effectiveness analysis of colorectal cancer screening in Shanghai, China: a modelling study

Age, frequency, and strategy optimization for organized colorectal cancer screening: a decision analysis conducted in China for the years 2023-2038

BACKGROUND

The colorectal cancer mortality rate in China has exceeded that in many developing countries and is expected to further increase owing to multiple factors, including the aging population. However, the optimal policy for colorectal cancer screening is unknown.

METHODS

We synthesized the most up-to-date data using a 12-state Markov model populated with a cohort of Chinese men and women born during 1949-1988, and evaluated 16 conventional and 40 risk-tailored schemes for colorectal cancer screening, considering possible combinations of age (starting at 40 + years and ending at 75 years), frequency, and strategy (standard colonoscopy, fecal immunochemical testing with colonoscopy if positive, or risk-tailored). We projected the incidence and mortality of CRC, cost, and quality-adjusted life years for 2023-2038; and performed incremental cost-effectiveness, probability acceptability, and sensitivity analyses to identify the optimal scheme and the factors affecting this choice.

RESULTS

By 2038, all standard colonoscopy, colonoscopy following fecal immunochemical testing, and risk-tailored schemes were effective in reshaping China's colorectal cancer trajectory, with relative reductions in colorectal cancer incidence and mortality rates of up to 34% and 33.7%, respectively, versus no screening. Two standard colonoscopy, one colonoscopy following fecal immunochemical testing, and four risk-tailored schemes were efficient using a starting age of 40 years. Among these options, a risk-tailored scheme (standard colonoscopy every 5 years for high-risk and annual fecal immunochemical testing screening for moderate-to-low-risk) had a high probability (31.1%) of being optimal (with ≥ 40% uptake for a high-risk population, in particular), given China's present per capita gross domestic product, and would yield the highest gain in quality-adjusted life years in 17 of 31 provinces.

CONCLUSIONS

Our findings suggest the commencement of colorectal cancer screening at 40 years of age in China, and that risk-tailored and some conventional schemes would be effective and cost-efficient. These findings should be valuable for policy-making regarding cancer control and resource allocation.

Efficient organized colorectal cancer screening in Shenzhen: a microsimulation modelling study

BACKGROUND

Colorectal cancer (CRC) is a global health issue with noticeably high incidence and mortality. Microsimulation models offer a time-efficient method to dynamically analyze multiple screening strategies. The study aimed to identify the efficient organized CRC screening strategies for Shenzhen City.

METHODS

A microsimulation model named CMOST was employed to simulate CRC screening among 1 million people without migration in Shenzhen, with two CRC developing pathways and real-world participation rates. Initial screening included the National Colorectal Polyp Care score (NCPCS), fecal immunochemical test (FIT), and risk-stratification model (RS model), followed by diagnostic colonoscopy for positive results. Several start-ages (40, 45, 50 years), stop-ages (70, 75, 80 years), and screening intervals (annual, biennial, triennial) were assessed for each strategy. The efficiency of CRC screening was assessed by number of colonoscopies versus life-years gained (LYG).

RESULTS

The screening strategies reduced CRC lifetime incidence by 14-27 cases (30.9-59.0%) and mortality by 7-12 deaths (41.5-71.3%), yielded 83-155 LYG, while requiring 920 to 5901 colonoscopies per 1000 individuals. Out of 81 screening, 23 strategies were estimated efficient. Most of the efficient screening strategies started at age 40 (17 out of 23 strategies) and stopped at age 70 (13 out of 23 strategies). Predominant screening intervals identified were annual for NCPCS, biennial for FIT, and triennial for RS models. The incremental colonoscopies to LYG ratios of efficient screening increased with shorter intervals within the same test category. Compared with no screening, when screening at the same start-to-stop age and interval, the additional colonoscopies per LYG increased progressively for FIT, NCPCS and RS model.

CONCLUSION

This study identifies efficient CRC screening strategies for the average-risk population in Shenzhen. Most efficient screening strategies indeed start at age 40, but the optimal starting age depends on the chosen willingness-to-pay threshold. Within insufficient colonoscopy resources, efficient FIT and NCPCS screening strategies might be CRC initial screening strategies. We acknowledged the age-dependency bias of the results with NCPCS and RS.

Effectiveness of Colorectal Cancer (CRC) Screening on All-Cause and CRC-Specific Mortality Reduction: A Systematic Review and Meta-Analysis

(1) Background: The aim of this study was to pool and compare all-cause and colorectal cancer (CRC) specific mortality reduction of CRC screening in randomized control trials (RCTs) and simulation models, and to determine factors that influence screening effectiveness. (2) Methods: PubMed, Embase, Web of Science and Cochrane library were searched for eligible studies. Multi-use simulation models or RCTs that compared the mortality of CRC screening with no screening in general population were included. CRC-specific and all-cause mortality rate ratios and 95% confidence intervals were calculated by a bivariate random model. (3) Results: 10 RCTs and 47 model studies were retrieved. The pooled CRC-specific mortality rate ratios in RCTs were 0.88 (0.80, 0.96) and 0.76 (0.68, 0.84) for guaiac-based fecal occult blood tests (gFOBT) and single flexible sigmoidoscopy (FS) screening, respectively. For the model studies, the rate ratios were 0.45 (0.39, 0.51) for biennial fecal immunochemical tests (FIT), 0.31 (0.28, 0.34) for biennial gFOBT, 0.61 (0.53, 0.72) for single FS, 0.27 (0.21, 0.35) for 10-yearly colonoscopy, and 0.35 (0.29, 0.42) for 5-yearly FS. The CRC-specific mortality reduction of gFOBT increased with higher adherence in both studies (RCT: 0.78 (0.68, 0.89) vs. 0.92 (0.87, 0.98), model: 0.30 (0.28, 0.33) vs. 0.92 (0.51, 1.63)). Model studies showed a 0.62-1.1% all-cause mortality reduction with single FS screening. (4) Conclusions: Based on RCTs and model studies, biennial FIT/gFOBT, single and 5-yearly FS, and 10-yearly colonoscopy screening significantly reduces CRC-specific mortality. The model estimates are much higher than in RCTs, because the simulated biennial gFOBT assumes higher adherence. The effectiveness of screening increases at younger screening initiation ages and higher adherences.