Factors associated with advanced colorectal cancer differ between young and older adults in England: a population-based cohort study.

Aim: Advanced stage presentation of colorectal cancer is associated with poorer survival outcomes, particularly among young adults. This study aimed to determine whether demographic risk factors for advanced stage presentation differed between young and older adults. Methods: Individual-level data on all incident colorectal cancer cases aged 20 years and above were extracted from the National Cancer Registration and Analysis Service database between 2012 and 2015. Patients were divided into two cohorts: young-onset colorectal cancer (YOCC) if aged 20-49 years and older-onset colorectal cancer (OOCC) if aged 50 years and above. Logistic regression was used to identify risk factors for advanced stage presentation, defined as TNM stage III or IV, in each cohort. Results: There were 7075 (5.2%) patients in the YOCC cohort and 128,345 (94.8%) patients in the OOCC cohort. Tumours in the YOCC cohort were more likely to be advanced stage (67.2% vs. 55.3%, p< 0.001) and located distally (63.7% vs. 55.4%, p< 0.001). No demographic factor was consistently associated with advanced stage presentation in the YOCC cohort. Among the OOCC cohort, increased social deprivation [Odds Ratio (IMD quintile 5 vs. 1) = 1.11 (95%Confidence Interval 1.07-1.16), p< 0.001], Black/Black British ethnicity [OR (baseline White) = 1.25 (95%CI 1.11-1.40), p< 0.001], and residence in the East Midlands [OR (baseline London) = 1.11 (95%CI 1.04-1.17), p=0.001] were associated with advanced stage presentation. Conclusion: Demographic factors associated with advanced disease were influenced by age. The effects of social deprivation and ethnicity were only observed in older adults and mirror trends in screening uptake. Targeted interventions for high risk groups are warranted.