Income Level and Survival After Resection of Liver Metastases: A Population-Based Study

This study aimed to investigate whether socioeconomic factors are associated with an improved long-term survival after colorectal cancer liver metastases (LM) resection.

A retrospective nationwide population-based cohort study. All patients who underwent hepatectomy in Sweden between 2002 and 2011 were identified in the Swedish Hospital Discharge Registry using their unique personal identification numbers. This cohort was linked to the National Cancer Registry (cancer diagnosis), the National Registry of Causes of Death, and the Migration Registry. Survival analysis by the Kaplan-Meier method was performed to assess long-term outcome. A Cox regression model was used to analyze risk factors affecting long-term survival.

In total, 2874 liver resections were performed in 2327 patients who were included in the study. In the group, 1362 (59%) were male and the median age was 65 (3-89) years. Patients that had more than one resection, the time was counted from the last resection. The main resection was a local resection that was performed in 60% of patients. The overall 5-year survival rate was 48%. In the univariate analysis, there was a significant association in overall survival for age, comorbidity, sex, income, and education level. In the adjusted multivariate logistic regression analysis, there was a significant relation with (higher OS, for lower age (HR 1.46 (95% CI: 1.23-1.72) and p < 0.001), lower comorbidity (HR 0.78 (95% CI: 0.66-0.92) and p < 0.003), female sex (HR 1.24 (95% CI: 1.05-1.47) and p = 0.01), and higher income (HR 0.84 (95% CI: 0.71-0.99) and p = 0.045)).

Patients that underwent surgery for LM from mainly colorectal disease and who have a low-income experience shorter overall survival. Further findings showed that patients with lower age and comorbidity and female sex had longer overall survival.