Advancing the Evaluation of Risk-Stratified Colorectal Cancer Screening by Simulating Quantitative Fecal Hemoglobin...

Area of Science:

• Oncology
• Gastroenterology
• Biostatistics

Background:

• Prior fecal hemoglobin (f-Hb) concentrations from fecal immunochemical tests (FITs) can predict future colorectal cancer (CRC) and advanced neoplasia.
• Current CRC screening models lack the ability to simulate quantitative f-Hb, hindering the evaluation of risk-based screening strategies.
• This limitation prevents the optimization of screening protocols based on individual f-Hb levels.

Purpose of the Study:

• To extend the MISCAN-Colon microsimulation model to simulate quantitative f-Hb concentrations.
• To enable the evaluation of risk-based CRC screening strategies tailored to individual f-Hb levels.
• To compare the effectiveness of uniform versus risk-based screening intervals.

Main Methods:

• A new module simulating quantitative f-Hb concentrations was integrated into the MISCAN-Colon model.
• The module utilized a zero-inflated negative binomial mixed-effect model, calibrated and validated with Dutch CRC screening program data (2014-2020).
• The updated model was applied to compare uniform biennial screening with risk-based intervals determined by f-Hb levels.

Main Results:

• The updated MISCAN-Colon model accurately reflected real-world positivity rates, CRC detection rates, and f-Hb distributions.
• Risk-based screening resulted in a slight increase in CRC cases (+5%) and deaths (+11%) compared to biennial screening.
• However, risk-based screening significantly reduced FITs (-28%) and colonoscopies (-13%).

Conclusions:

• The integration of an f-Hb module into MISCAN-Colon allows for explicit modeling of f-Hb concentrations.
• This advancement facilitates the evaluation of risk-based screening strategies based on prior f-Hb concentrations.
• Risk-based screening holds potential for optimizing CRC screening efficiency and resource allocation.