Global Burden and Future Trends of Gastrointestinal Cancers in Adolescents and Young Adults, 1990-2045: A Predictive Analysis.

[PURPOSE] Gastrointestinal (GI) cancers significantly contribute to the global cancer burden, yet their epidemiological trends among adolescents and young adults (AYAs: aged 15-39 years) remain understudied. This study provides the first comprehensive analysis of global burden, temporal trends (1990-2021), and projections to 2045 for GI cancers in AYAs.

[METHODS] Using the Global Burden of Disease (GBD) 2021 dataset, we analyzed age-standardized incidence rates (ASIR), death rates (ASDR), disability-adjusted life-years (DALYs), and estimated annual percentage changes (EAPC). Bayesian age-period-cohort modeling was employed for projections to 2045.

[RESULTS] In 2021, there were 156,033 new GI cancer cases, 84,623 deaths, and 4.9 million DALYs among AYAs globally. From 1990 to 2021, ASIR for colorectal and gallbladder cancers increased (EAPCs:0.55[95%CI:0.44, 0.67] and 0.13[0.05, 0.20], respectively), while ASIR for other GI cancers declined (e.g., stomach cancer:-2.75 [- 2.94, - 2.57]). East Asia bore the highest burden. Projections suggest a stabilization of overall ASIR and ASDR by 2045, though liver and gallbladder cancers are expected to rise.

[CONCLUSIONS] The burden of GI cancers among AYAs remains substantial and is projected to persist, highlighting the need for targeted early-detection strategies and age-specific prevention programs, especially in high-risk regions.