Risk-Adapted Starting Age for Personalized Colorectal Cancer Screening: Validated Evidence From National Population-Based Studies

A one-size-fits-all approach to colorectal cancer (CRC) screening that does not account for CRC risk factors is not conducive to personalized screening. On the basis of the principle of equal management of equal risks, we aimed to tailor and validate risk-adapted starting ages of CRC screening for individuals with different CRC risk factors.A multi-center community-based population cohort (N = 3,165,088) was used to evaluate the starting age of CRC screening with comprehensive consideration of risk factors. Age-specific 10-year cumulative risk curves were used to determine when individuals at greater risk for CRC reached the same risk level as the 50-year-old general population, which is currently the recommended starting age for CRC screening in China.During the study follow-up period (2013-2021), 4,840 incident CRCs were recorded. Family history of CRC, adverse lifestyle, and comorbidities demonstrated heterogeneous associations with CRC risk (hazard ratios, 1.05-1.55; P < .05). Men and women with CRC family history and at least 2 risk factors reached the standard benchmark risk (0.28%) for screening at the age of 40, 10 years earlier than their peers without risk factors in the general population. Proposed starting ages for CRC screening were validated in an independent community-based population cohort (N = 1,023,367).We determined a risk-adapted CRC screening starting age for individuals with various CRC risk factors. Earlier, personalized screening based on these findings could allow for scarce health resources to be dedicated to individuals who benefit most.