Differences in characteristics and outcomes between early-onset colorectal cancer and late-onset colorectal cancers

Introduction: Colorectal cancer (CRC) represents a significant health burden worldwide, with a notable increase in early-onset colorectal cancer (EOCRC) cases, defined as those diagnosed before the age of 50 years. Materials and methods: Using data from Taiwan's national cancer registry and a retrospective cohort from Chang Gung Memorial Hospital, this study analyzed CRC cases diagnosed between 2008 and 2019. The analysis compared the EOCRC and late-onset CRC (LOCRC) groups in terms of clinicopathological characteristics, prediagnostic symptoms, and survival outcomes. Results: The analysis revealed a continuous increase in the annual incidence of EOCRC, with colon cancer and rectal cancer rising by 3.2 % and 3.3 %, respectively. Patients with EOCRC presented with more aggressive disease characteristics, such as signet-ring cell adenocarcinoma, mucinous adenocarcinoma, and poorly differentiated grade. Advanced stages at diagnosis, stages III and IV, were more common with EOCRC (62.4 %) than with LOCRC (50.3 %). Patients with EOCRC reported rectal bleeding, changes in bowel habits, and abdominal pain more frequently than those in the LOCRC group. There is a strong association between stool-related symptoms and left-sided CRC. Despite similar surgical outcomes, the 5-year cancer-specific survival rate of patients with stage IV EOCRC was significantly lower than that of patients with LOCRC (32.8 % vs. 51.9 %, p = 0.012). Conclusion: This study highlights a persistent rise in the incidence of EOCRC, with patients presenting with more aggressive disease and experiencing inferior survival. These findings underscore the importance of heightened awareness and early detection strategies for CRC, especially in younger populations, to improve the prognosis.