Impact of comorbidity and relative dose intensity on outcomes in diffuse large B-cell lymphoma patients treated with R-CHOP

Background Comorbidity and relative dose intensity (RDI) have been associated with survival in diffuse large B-cell lymphoma (DLBCL) patients, but both relationships remain unaddressed in the same patients. Methods A retrospective review of consecutive DLBCL patients treated from January 2010 to October 2018 was performed. Data for the clinical characteristics of the patients, including the Charlson Comorbidity Index (CCI) and RDI, on their outcomes were evaluated. Results A total of 211 patients with a median age of 72 years (range 19-90 years) were analyzed. CCI >= 2 was associated with poor event-free survival (EFS) and overall survival (OS). RDI < 70% was associated with worse EFS and OS. A multivariate analysis revealed that RDI < 70% was only a poor risk factor for the reduction of OS in elderly DLBCL patients (65 years <) and independent from the presence of CCI. The relationship between CCI and RDI in elderly patients was analyzed in four groups, based on CCI >= 2 or less and RDI >= 70% or less. The group with CCI >= 2 and RDI < 70% had a poorer OS and EFS, as compared to the other three groups. The group with CCI < 2 and RDI >= 70% had a superior OS but an identical EFS, as compared to the two groups with CCI < 2 and RDI < 70% and CCI >= 2 and RDI >= 70%. Conclusions CCI >= 2 was associated with a poorer outcome, but maintaining RDI >= 70% may improve the outcome, especially in elderly DLBCL patients.