Socioeconomic Disadvantage, but Not Remote Location, Is Associated With Poorer Survival After Resection of Colon Cancer in Queensland Patients: A Population‐Based Retrospective Cohort Study

BACKGROUND: Previous studies have demonstrated a social gradient in survival outcomes for colorectal cancer. The aim of this study was to determine the effect of socioeconomic status and geographic remoteness on overall (OS) and cancer-specific survival (CSS) for patients with non-metastatic colon cancer in Queensland. METHODS: A population-based retrospective cohort study between 1 January 2001 and 30 December 2021 utilising data from the Queensland Oncology Repository. RESULTS: A total of 29 749 patients met the inclusion criteria, with a median follow up time of 71 months. Both OS and CSS for those that were socioeconomically disadvantaged were significantly lower than those who were middle SES and affluent at all-time points (p < 0.001). In multivariate Cox proportional hazards analysis, after accounting for age, stage, sex, ASA and geographic remoteness, the hazard ratio (HR) for overall and cancer-specific death in those that were disadvantaged compared to those that were affluent and middle SES was 1.13 (95% 1.01-1.25, p = 0.03) and 1.18 (95% CI 1.01-1.39, p = 0.04), respectively. Patients who were socioeconomically disadvantaged were less likely to be from a major city than those who were middle SES and affluent (32.8% vs. 70.2% and 97.1%, respectively, p < 0.001). Geographic remoteness itself had no effect on OS or CSS in multivariate analysis. CONCLUSION: Despite significant advances in healthcare, socioeconomic disadvantage remains a predictor of poor prognosis for patients with non-metastatic colon cancer in Queensland. Further efforts are needed to ensure equitable provision of services to improve outcomes in this vulnerable population.