Outcomes of cardiac diffuse large B-cell lymphoma (DLBCL) in the rituximab era

Background Cardiac diffuse large B-cell lymphoma (cDLBCL) is an extremely rare disease. Introduction of rituximab has significantly improved survival in non-cardiac DLBCL, but there is limited data regarding the effects on outcomes in cDLBCL. We sought to evaluate the outcomes of cDLBCL in both pre- and rituximab eras. Methods We identified all cDLBCL cases in the Surveillance, Epidemiology and End Results (SEER) registry from 1975 to 2016. We compared survival (overall and lymphoma-specific) of patients diagnosed prior to versus after rituximab approval in 2006. Results A total of 106 patients were included in the final analysis. Median age was 69.5 years, 67% of the patients were white and 64% had local stage I/II disease. 67% of the patients were diagnosed after 2006 and thus belonged to the rituximab era group. Overall, 77% received chemotherapy, 24% had surgery and 15% had radiotherapy. Median overall survival (OS) for the entire cohort was 22 months. Median OS was 16 months (95% CI, 0.55-31) for the pre-rituximab group, versus 26 months (95% CI, 7.5-45) for the rituximab group (p = 0.34). Median lymphoma-specific survival (LSS) was 30 months (95% CI, 8.0-52) for the pre-rituximab group versus 36 months (95% CI, 16-158) for the rituximab group (p = 0.30). OS and LSS were also not significantly different between the two era groups when stratified by chemotherapy. In multivariable analysis, both OS and LSS were associated with lymphoma stage, insurance status and age but not with diagnosis era or chemotherapy. Conclusions Cardiac DLBCLs are rare and affecting mostly the elderly. Younger age, limited disease stage, and having health insurance but not lymphoma diagnosis era were associated with better outcomes.