Association Between Socioeconomic Position and Diagnosis, Treatment and Survival of Patients With Stage I-III Rectal Cancer in the Netherlands.

Socioeconomic position (SEP) influences cancer care and outcomes, even in countries with government-funded healthcare. This population-based study examined associations between SEP, rectal cancer care and survival of patients in the Netherlands. Data from 25,995 patients with Stage I-III rectal cancer diagnosed between 2015 and 2023 were obtained from the Netherlands Cancer Registry. SEP was categorised as lower, intermediate or higher using income-based postal code data. Associations between SEP and detection method, treatments, and outcomes were analysed using multivariable logistic regression. Relative survival and relative excess risk (RER) of death were calculated using a generalised linear model. Compared to lower SEP, higher SEP patients were younger (median age 66 vs. 71 years), more often male (65% vs. 59%), had better performance status (71% vs. 52% PS0), fewer comorbidities (63% vs. 50% CCI 0) and lower obesity rates (15% vs. 23%). Higher rates of Stage I tumours (34% vs. 30%), screen-detection (45% vs. 38%), laparoscopic surgery use (93% vs. 90%), and lower rates of colostomies (64% vs. 71%) and adverse in-hospital outcomes (44% vs. 55%) were observed among higher SEP patients (all p < 0.001). Five-year relative survival improved with increasing SEP (79.5% lower, 82.4% intermediate, 84.9% higher SEP; p < 0.001), with lower excess mortality for higher SEP patients (RER 0.90, 95% CI 0.81-0.99). SEP-related differences were observed in screening, stage at diagnosis, surgical treatment and survival. Although several disparities were partly explained by comorbidity and BMI, others persisted, highlighting the need for targeted strategies to reduce differences between SEP groups in rectal cancer management and outcomes.