Association between Comorbidity and Relative Dose Intensity in Patients with Diffuse Large B-Cell Lymphoma

Comorbidities among cancer patients are becoming more common. Comorbidity and relative dose intensity (RDI)are 2 major host-dependent prognostic factors for diffuse large B-cell lymphoma(DLBCL), but the clinical evidence demonstrating a relationship between those 2 factors is limited.

We retrospectively analyzed the clinical records of patients with de novo DLBCL treated with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisolone(R-CHOP) therapy at the Okitama Public General Hospital between January 2010 and October 2018 to evaluate the relationship between comorbidity and RDI.

A total of 104 patients with a median age of 73 years(range, 36-90 years)were included. More than half of the patients(n=58, 55.8%)had at least one comorbidity. 3-year progression-free survival(p=0.043)and 3- year overall survival(p=0.049)were lower in the comorbidity group than in the no comorbidity group. The RDI was also lower in the comorbidity group than in the no comorbidity group(p=0.011). Univariate analysis of various factors influencing the RDI revealed that the presence of comorbidity was associated with insufficient RDI(p=0.016), but multivariate analysis revealed that only age ≥75(p<0.001)was independently associated with insufficient RDI.

Our results demonstrated that the presence of comorbidity was associated with insufficient RDI and poor treatment outcome in DLBCL patients treated with R-CHOP. To optimize the RDI maintenance to achieve better outcomes for DLBCL patients, further investigation of comorbidities is required.