Background: Diffuse large B cell lymphoma (DLBCL) is the most common non-Hodgkin lymphoma. The treatment response and overall survival (OS) improved after incorporating rituximab with chemotherapies. Yet, available evidence as to whether women and men may benefit similarly from rituximab have not been adequately addressed, particularly in the real-world setting. The objective of this study was to examine sex differences in the clinical outcomes of rituximab in DLBCL patients using the Taiwan Cancer Registry Database and National Health Insurance Research Database.
Materials and methods: All DLBCL patients aged 20 years and older during 2009-2013 were identified (n = 4490; women = 2048). Cox proportional hazard models were used to compare the results.
Results: The baseline characteristics were similar between women and men with DLBCL, except that women had lower Charlson comorbidity index (CCI), and that fewer women underwent R-CHOP. In the survival analysis, women had better OS and longer time to treatment failure. The multivariate analysis of OS showed that the female sex remained to be an independent favorable prognostic factor regardless of Ann Arbor stages, age, treatments, CCI, and practice settings. In the subgroup analysis, the female advantage was only significant in the patients receiving rituximab-CHOP chemotherapy instead of in those receiving other rituximab-containing or non-rituximab therapies. This advantage diminished when rituximab dose was higher.
Conclusion: From our population-based study, women demonstrated more survival benefits from the use of rituximab-containing induction chemotherapies for DLBCL.
Keywords: Taiwan Cancer Registry Database; diffuse large B cell lymphoma; rituximab; sex difference.