https://orcid.org/0000-0001-9306-2945
KEY POINTS
∼20% of patients with DLBCL received second line treatment, with 5-year OS of 26%, influenced by age, relapse timing, and treatment intent
These findings highlight the ongoing need for effective, accessible therapies, and provide a benchmark for future studies
ABSTRACT
Given the rapidly evolving treatment landscape for diffuse large B cell lymphoma (DLBCL), we performed a contemporary analysis of survival outcomes in patients aged ≥18 years with DLBCL at the population level using linked administrative datasets in Ontario, Canada (ICES). Among 8,675 patients (median age 67, 44% female) treated with frontline rituximab-based therapy, 1,675 (19%) were treated with second-line therapy (2L). The 2-year and 5-year overall survival (OS) from 2L were 33% and 26%, respectively. Univariate analysis demonstrated that curative-intent therapy (autologous stem cell transplant [ASCT]) (58% of patients) was associated with better OS compared to palliative radiotherapy (hazard ratio [HR] 0.56, p<0.0001). Patients ≥60 years showed inferior OS compared to those <60 (age 60-69: HR 1.35, p=0.0002; age 70-79: HR 1.64, p<0.0001; age ≥80: HR 2.08, p<0.0001). Additionally, early relapse was associated with worse outcomes compared to relapses occurring after 2 years (<3 months: HR 1.45, p=0.0002; 3-6 months: HR 1.51, p=0.0001; 6-12 months: HR 1.88, p<0.0001). Multivariable analysis confirmed these associations, while accounting for LDH, comorbidity burden, frailty, and income. Exploratory analysis indicated that third-line chimeric antigen receptor T cell therapy (CAR-T) was associated with improved outcomes compared to a historical cohort of patients treated with palliative therapy prior to 2020 (2-year OS 56% vs. 21%). This population-based analysis suggests that curative intent therapy (ASCT and CAR-T) is associated with improved OS over conventional treatment approaches. The outcomes presented here provide benchmarks for future analyses aimed at assessing the effects of novel treatments in the 2L on outcomes.
Author notes
Data sharing: The data set from this study is held securely in coded form at ICES. While legal data sharing agreements between ICES and data providers (e.g., health care organizations and government) prohibit ICES from making the data set publicly available, access may be granted to those who meet prespecified criteria for confidential access, available at http://www.ices.on.ca/DAS (email: das@ices.on.ca).
NOVELTY
Population-based studies following the integration of CAR-T are limited. In this study of 8,675 patients with DLBCL, we show that curative-intent treatments including second-line ASCT and third-line CAR-T, improve survival compared to palliative-intent treatments. Advanced age and early relapse were additional factors associated with worse survival. Our study provides a benchmark for future research on the effectiveness of new therapies on outcomes in unselected patients with DLBCL.
