Population based registry study on large B-cell lymphoma mortality and morbidity in Finland.

Abstract

Background: Large B-cell lymphomas (LBCLs) form a notable subgroup of lymphomas; however, their associated long-term comorbidities and mortality rates remain under-researched in real-world settings.

Material and methods: This nationwide Finnish population-based matched cohort study included virtually all LBCL patients (N = 7,019) diagnosed from 2008 to 2019, alongside age, sex, and region-matched controls (1:1 ratio) without lymphoma. Diagnoses of LBCLs were obtained from the Finnish Cancer Registry, with data linked to additional nationwide registries. Baseline characteristics were summarised using descriptive statistics. Overall survival (OS) was estimated using the Kaplan-Meier method, while Cox regression was used to analyse factors associated with OS and evaluate the risk and associated factors of comorbidities considering the competing risk of death.

Results: The 5-year survival rate for LBCL patients, median age 70.7 years and 52.7% male, was 50.0% (95% Confidence Interval [CI] 48.7% - 51.3%), compared to 82.6% (95% CI 81.5% - 83.6%) for controls. Among LBCL patients, older age and a higher Charlson comorbidity index were associated with increased mortality. Conversely, female sex, later diagnosis year, and radiation therapy were associated with improved survival. Patients with LBCL exhibited an elevated risk of long-term comorbidities, including solid tumours, hematological and skin cancers, lung and thyroid diseases, mental and behavioral disorders, and cardiovascular diseases. After 12 years of follow-up, lymphoma accounted for the primary cause of death in approximately 43% of LBCL patients.

Interpretation: Large B-cell lymphomas are linked with significant long-term comorbidities and elevated mortality rates.