S490 Epidemiological Trends and Survival Outcomes of Early Onset Colon and Rectal Cancer: An Analysis of SEER 2018-2022 Data Among Patients Under 50 Years

Introduction: Early-onset colorectal cancer (CRC), defined as diagnosis before 50 years of age, has emerged as a significant clinical challenge despite traditionally lower incidence in younger populations. Understanding incidence rates and survival trends in this demographic is critical for targeted public health interventions and optimized clinical management. Methods: We analyzed data from the Surveillance, Epidemiology, and End Results (SEER) Program covering 2018–2022, focusing on colon and rectal cancers (including appendix) in patients under 50 years. Age-adjusted incidence rates per 100,000 population and 5-year relative survival trends were examined. Incidence rates included 95% confidence intervals (CI). Survival trends assessed average annual absolute changes with associated 95% CIs, highlighting directionality over a 22-year period (2000–2022). Results: The age-adjusted incidence rate for patients under 50 was 9.0 per 100,000 (95% CI: 8.9–9.1), representing 42,645 cases out of a total 319,746 SEER cases across all ages. Analysis of 5-year relative survival revealed a statistically significant decline, with an average annual decrease of –0.4% (95% CI: –0.7 to –0.2), indicating worsening survival outcomes in younger patients despite advances in cancer care. Conclusion: Our findings reveal a concerning rise in early-onset colorectal cancer incidence paired with a declining 5-year survival rate among patients under 50 years. This trend underscores the need for heightened awareness, earlier screening strategies, and tailored therapeutic approaches for this vulnerable group. Future research should explore biological, environmental, and socioeconomic factors contributing to these trends to improve outcomes.