Heterogeneity in survival within age groups of early-onset colorectal cancer patients: A National Cancer Database analysis

Background: We aimed to identify predictors of and heterogeneity in survival among different age groups of patients with early-onset colorectal cancer (EOCRC). Methods: This retrospective cohort study used National Cancer Database data from 2004 to 2019. Differences in survival among CRC patients <50 years, subcategorized into age groups (<20, 20–29, 30–39, 40–49 years) were compared for demographic, clinical, and histologic features by univariate and multivariate analyses. Cox hazard regression and Kaplan Meier survival analysis were performed. Results: 134 219 of the 1 240 787 individuals with CRC (10.8%) were <50 years old; 46 639 (34.8%) had rectal and 87 580 (65.3%) had colon cancer. Within the colon cancer cohort, individuals aged between 30 and 39 years had the highest overall survival rate (66.7%) during a median follow-up of 47.6 months (interquartile range IQR 23.1–89.7). The same age group in the rectal cancer cohort had the lowest survival rate (31%) over a median follow-up of 54.5 (IQR 28.24–97.31) months. Leading factors affecting survival included tumor stage (HR 8.23 [4.64–14.6]; p < 0.0001), lymphovascular invasion (HR 1.88 [1.70–2.06]; p < 0.0001) and perineural invasion (HR 1.08 [1.02–1.15]; p = 0.001). Conclusion: Survival trends vary within age groups of patients affected with early onset colon cancer compared to rectal cancer. Tumor stage and unfavorable pathological characteristics are the strongest factors predicting survival.