Early-onset vs. late-onset colorectal cancer trends among veterans

The purpose of this study was to evaluate trends in the incidence and mortality of early-onset CRC (age at diagnosis < 50), vs. late-onset CRC (age at diagnosis = 50). A secondary objective is to compare characteristics and outcomes among Black and White Veterans among patients with early-and late-onset CRC. This study was a retrospective analysis of a national cohort of Veterans identified in the Veterans Administration (VA) Oncology database with a diagnosis of CRC between 2012 and 2017. The PRECEDE model was used to guide this study. Descriptive statistics were used to compare characteristics among early-onset and late-onset patients and evaluate Black and White differences within both groups of CRC patients. Chi-square analyses, logistic regression, and Kaplan-Meier methods were the statistical analyses used to answer the research questions. In this cohort of 13,940 patients, early-onset accounted for approximately 4% (N=604) and remained consistent each year, while late-onset represented approximately 96% (N=13336) of patients and remained stable over the years. The sample was majority male (96.06%). The females were majority early-onset (12.09%) compared to 3.01% late-onset. The Black-White race distribution was (28.48%/71.52%) in early-onset and (19.84%/80.16%) for late-onset. The following predisposing factors (age, race, marital status, tobacco history, health conditions, and BMI) and the enabling factors treatment and additional health insurance were statistically significant among early-versus late-onset CRC (all p<0.0001). Findings from this study emphasize the importance of distinguishing between early-onset CRC and late-onset CRC to understand the unique characteristics of early-onset disease better, and factors contributing to racial differences in both early-and late-onset CRC