Retrospective study of treatment distributions, treatment responses, toxicities, survival and factors affecting these in patients aged 60 and over with diffuse large B-cell lymphoma

Introduction: Non-Hodgkin lymphomas (NHL) are the most common hematologic malignancies. Diffuse large B-cell lymphoma (DLBCL) is the most common subtype within the NHL group, accounting for approximately 30-40% of NHL cases. Advanced age is a poor prognostic factor for DLBCL. In the elderly patient group, the treatment modality is determined considering the accompanying comorbidities. This study aims to contribute to identifying optimal treatment strategies for elderly patients diagnosed with DLBCL. Materials and Methods: This study was a single-center, retrospective analysis. It examined patients aged 60 and over diagnosed and treated for DLBCL between 2008 and 2023. The study analyzed the treatment regimens, response, toxicity, overall survival (OS), and progression-free survival (PFS) of patients considering their age, comorbidities, stage, performance status, prognostic scores, and immunohistochemical evaluations. Results: Data from 186 patients were evaluated. The median age at diagnosis was 71 years (range 60-90), and the median follow-up period was 19 months (range, 1-129 months). Among the 186 patients, 48.4% (n=90) were male and 51.6% (n=96) were female. The 5-year OS for the entire group was 75%, and the 5-year PFS was 70%. The median OS for the entire group was 70 months (range 1-129 months, 95% CI: 53-86). Patients were categorized into three age groups: 60-69, 70-79, and ≥80 years. There was a significant survival difference among these subgroups (p=0.001). Significant differences in survival were observed between the 60-69 age group and the other two groups (p=0.006 and p=0.001, respectively). There was no significant survival difference between the 70-79 and ≥80 age groups (p=0.207). Histological subtypes (Germinal center like and non germinal center) did not impact survival (p=0.159). Each year increase in age was associated with a 7% increase in mortality risk (HR 1.07, 95% CI: 1.04-1.11, p<0.001). The median OS for the ECOG 0-1 group was 104 months (range, 64-143 months), while for the ECOG ≥2 group, it was 22 months (range, 5-38 months) (p<0.001). The mortality risk for the LDH ≥250 U/L group was 2.9 times higher than the normal group (HR 2.90, 95% CI: 1.70-4.95, p<0.001). In the group with CRP >15 mg/dL, the median OS was 33 months (range, 5-60 months), compared to 95 months (range, 75-114 months) in the group with CRP <15 mg/dL (p=0.002). Cox regression analysis showed that the mortality risk for the CRP >15 mg/dL group was 2.2 times higher compared to the reference group (HR 2.16, 95% CI: 1.28-3.63, p=0.002). The mortality risk in the albumin <3.5 g/dL group was 2.45 times higher than in the albumin ≥3.5 g/dL group (HR 2.45, 95% CI: 1.49-4.03, p<0.001). There was a survival difference between the R-CHOP and R-CVP groups (p=0.021). The median OS was 78 months in the R-CHOP group (95% CI: 48-101) and 16 months in the R-CVP group (95% CI: 4-27). The median OS in the R-miniCHOP group was 28 months (95% CI: 23-40) (p=0.201). There was no difference in the incidence of side effects among treatment protocols (p=NS). Conclusion: In this study, it has been demonstrated that elevated LDH levels, the presence of advanced-stage disease, and increasing age reduce survival in elderly patients with DBBHL (Diffuse B-cell B-Lymphoma). The IPI, R-IPI, and NCCN-IPI scores, which are used to predict prognosis in all age groups, are anticipated to be insufficient in identifying poor prognostic patients in the elderly population. There is a need for prognostic modeling using more accessible and easier parameters in this context. In our study, the effects of CRP and albumin on survival were also shown, yet there remains a need for studies with larger patient cohorts to establish sufficient reliability for clinical use in predicting prognosis. Keywords: Diffuse Large B Cell Lymphoma (DLBCL), Eastern Cooporative Oncology Group (ECOG), Overall Survival (OS), Progression Free Survival (PFS)