Burden and forecast of colorectal cancer in the selected East Asian countries (1990-2036): a systematic analysis based on the global burden of disease study 2021.

[BACKGROUND] Colorectal cancer (CRC) is a leading global cause of cancer morbidity and mortality, yet how its burden has shifted during rapid demographic and lifestyle change in East Asia remains poorly characterized. This study fills that gap by examining long‑term trends and drivers of CRC burden in the selected East Asian countries-China, Japan, North Korea, South Korea, and Mongolia-between 1990 and 2021, and by projecting future burden through 2036.

[METHODS] We obtained data from the Global Burden of Disease (GBD) Study 2021 on CRC-related prevalence, incidence, mortality, years lived with disability (YLDs), years of life lost (YLLs), and disability-adjusted life years (DALYs) in the selected countries, further assessed by age and sex. We quantified contributions of population growth, aging and epidemiological change decomposition analysis, characterized temporal trends with Joinpoint and age-period-cohort analysis, and generated forecasts to 2036 using Autoregressive Integrated Moving Average and Bayesian age-period-cohort approaches.

[RESULTS] Although absolute CRC burden rose across the region-driven largely by population aging-with China exhibiting the highest numbers and Japan exhibiting the highest age‑standardized rates. Older adults bore the greatest share of burden. Decomposition and modeling indicate that demographic shifts have been the predominant force behind increasing CRC counts, and projected trends suggest the regional burden will remain substantial without targeted action.

[CONCLUSIONS] This study provides novel, region‑specific evidence that demographic aging is the principal driver of rising CRC burden in East Asia. The findings highlight an urgent need for tailored prevention, screening and resource planning focused on aging populations to alter the projected trajectory.