THE RELATIONSHIP BETWEEN AREA-LEVEL MARGINALIZATION AND THE OVERALL SURVIVAL OF SOFT-TISSUE SARCOMA PATIENTS IN ONTARIO: A RETROSPECTIVE COHORT STUDY

Socioeconomic status and community marginalization can be a predictor of overall survival and functional outcome in patients with a cancer diagnosis. However, this association has yet to be determined in patients with soft tissue sarcoma (STS) within Canada. The primary aim of this study was to determine the impact of marginalization on STS 5-year overall survival. We conducted a retrospective cohort study of patients presenting with primary or locally recurrent STS and who underwent surgical resection between January 2010 and December 2021. Marginalization was determined using the Ontario Marginalization Index (ON-Marg), and patients were stratified into quintiles (Q1-Q5), with Q1 representing individuals living in the least marginalized communities, and Q5 representing the most marginalized. Three subdomains of the ON-Marg included in this study were Ethnic Concentration, Material Resources, and Household Dwelling. The association between marginalization and overall survival was determined using Kaplan-Meier curves and a multivariate cox proportional hazards model. When adjusted for age and grade of disease, 5-year overall survival was not impacted by Ethnic Concentration (75.2% Q1 vs. 80.5% Q5). However, 5-year overall survival was significantly affected by increasing marginalization within Material Resources (81.9% Q1 vs 69% Q5) and Household Dwelling (82.2% Q1 vs 69.6% Q5). Additionally, there were no significant differences across quintiles with regards to 1-year functional outcomes, measured using the Toronto Extremity Salvage Score and the Musculoskeletal Tumor Society Score-93. This study is the first to demonstrate that marginalization is an independent risk factor adversely impacting 5-year overall survival of STS in Canada's single payer universal healthcare system. Social risk factors should be considered when devising a treatment plan for STS.