Background: For Diffuse large B-cell lymphoma (DLBCL), the International Prognostic Index is the major tool for prognostication and considers an age above 60 years as a risk factor. However, there are several indications that increasing age is associated with more biological complexity, resulting in differences in DLBCL biology depending on age.
Methods: We conducted a registry-based retrospective cohort study of all Swedish DLBCL patients diagnosed 2000-2013, to evaluate the importance of age at diagnosis for survival of DLBCL patients.
Results: In total, 7166 patients were included for further analysis. Survival declined for every 10-year age group and every age group above the age of 39 had a statistically decreased survival compared to the reference group of 20-29 years. In an analysis of relative survival, and in a multifactorial model adjusted for stage, ECOG performance status, serum lactate dehydrogenase and involvement of extranodal sites, each age group above age 39 had a significantly higher risk ratio (p=0.01) compared to the reference group.
Conclusion: This is one of the largest population-based studies of DLBCL published to date. In this study, age persisted as a significant adverse risk factor for patients as young as 40 years, even after adjustment for other risk factors.