The impact of marginalization on diffuse large B-cell lymphoma overall survival: a retrospective cohort study

Abstract

The aim of this study was to describe the impact of marginalization on DLBCL overall survival (OS) within the Canadian setting. We conducted a population-based retrospective cohort study of adult patients with newly diagnosed DLBCL in Ontario between 1 January 2005 and 31 December 2017 receiving a rituximab-containing chemotherapy regimen with curative intent followed until 1 March 2020. Our primary exposure of interest was the Ontario Marginalization Index (ON-Marg). The primary outcome was 2-year OS, accounting for patient age, sex, cancer characteristics, comorbidity burden, and rural dwelling status. While two-year overall survival was inferior for individuals in the most deprived marginalization quintile (70.4% Q5 vs. 76.0% Q1), after adjustment for relevant covariates neither the composite ON-Marg nor any of its dimensions had a significant effect. Within the Canadian context, among patients who receive chemotherapy, marginalization may not have a significant association with overall survival when accounting for key patient covariates, lending support for preserved outcomes.

Keywords:

• Lymphoma
• health equity
• survival

Acknowledgments

Parts of this material are based on data and/or information provided and compiled by Cancer Care Ontario (CCO), Canadian Institute for Health Information (CIHI), and the Ontario Registrar General (ORG) information on deaths, the original source of which is Service Ontario. The views, analyses, and conclusions expressed herein are solely those of the authors and do not reflect those of the funding or data sources. No endorsement is intended or should be inferred.

Author contributions

SA contributed to conceptualization, methodology, investigation, formal analysis, visualization, and writing the manuscript. LM and MC contributed to conceptualization, methodology, investigation, supervision, and reviewing and editing. IG contributed to conceptualization, methodology, and reviewing and editing. NF and NL contributed to data curation, formal analysis, software, and reviewing and editing. SS and KC contributed to investigation, visualization, and reviewing and editing.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Role of the funder

Not applicable.

Additional information

Funding

This study was supported by ICES, which is funded by an annual grant from the Ontario Ministry of Health (MOH) and the Ministry of Long-Term Care (MLTC). Matthew Cheung receives funding from Marjorie and Roy Linden and Iris Sommer and Stephen Daly.