Emerging evidence suggests that the incidence of colorectal cancer is increasing among individuals under the age of 50 years. However, the pattern of disease presentation in young patients remains under investigation. This is a retrospective cohort study of patients diagnosed with colorectal cancer (CRC) between 2004 and 2015. Data was acquired from the Surveillance, Epidemiology, and End Results 18 program registries. A total of 269,398 patients who met the inclusion criteria were included in the final analysis. The primary outcomes were the likelihood of metastatic disease at diagnosis and survival. Of the 269,389 patients diagnosed with CRC, 11.8% of the patients were young (20 to 49 years), 45.6% were middle-aged (50 to 69 years), and 42.6% were elderly (70 years or older). Individuals in the middle-aged and elderly cohorts were significantly less likely to present with metastatic disease as compared to the young cohort (middle-aged adjusted odds ratio (aOR) = 0.73, 95% confidence interval (CI) = 0.70 to 0.75, elderly aOR = 0.49, 95% CI = 0.47 to 0.50). However, overall survival was longest in the young cohort. We conclude that young individuals with colorectal cancer have an increased risk of presenting with distant metastases as compared to the middle-aged and elderly, but, nevertheless, exhibit prolonged survival.
Keywords: cohort; colorectal cancer; metastatic; surveillance epidemiology and end results; survival; young.