Revisiting the Starting Age of Colorectal Cancer Screening for Average-Risk Asian Population: a cost-effectiveness analysis.

Background And Aims: One of the most prevalent and fatal tumors, colorectal cancer (CRC) has a significant impact on the use of healthcare services. Although Hong Kong's CRC screening program has been successful, it does not prioritize preventing early-onset colorectal cancer in people under 50. This study aimed to assess the cost-effectiveness of different starting ages for colorectal cancer (CRC) screening among an Asian population.

Methods: We conducted a simulation study involving 100,000 individuals in Hong Kong who were screened using either fecal immunochemical test (FIT) or colonoscopy as primary screening methods at ages 40, 45, and 50 until age 75. The performance of different strategies was evaluated based on life-years gained, and cost-effectiveness was measured using the incremental cost-effectiveness ratio (ICER).

Results: The ICERs for initiating FIT screening at age 50, screening starting at age 45, and screening starting at age 40 were USD 53,262, USD 67,892, and USD 86,554, respectively. For colonoscopy, the ICERs for initiating screening at ages 50,45 and 40 were USD 267,669, USD 312,848, and USD 372,090, respectively, respectively. Overall, the FIT strategy was found to be less costly. At 70%, 80% and 90% compliance rates, FIT at age 45 gained 2,135, 2,296 and 2,438 life years respectively; colonoscopy at age 45 gained 2,725, 2,798 and 2,855 life-years respectively. With increased compliance rates, FIT could save a similar number of life years as colonoscopy with lower cost.

Conclusions: Initiating CRC screening at age 45 using FIT in Hong Kong was determined to be a well-balanced and cost-effective strategy. This approach demonstrated a cost advantage over starting screening at age 40 and resulted in more lives saved compared to screening at age 50.