Survival Trends Among Very Elderly Patients with Advanced Diffuse Large B-Cell Lymphoma - a Population Based Study
Authors: Shah Binay K. , Ghimire Krishna B , Pendharkar Dinesh 
Published: November 2019

Abstract
Background
Rituximab became commercially available in Novermber 1997. It was FDA approved in February 2006 for the first line treatment of patients with advanced diffuse large B cell lymphoma (DLBCL). The incidence of diffuse large B cell lymphoma increases with age, with >100 cases per 100000 persons aged >80 years. There is a limited data on survival very elderly patients with DLBCL. This study was conducted to evaluate survival trends of very elderly (≥80 years) patients with advanced DLBCL in the United States.
Methods
We selected very elderly patients (age ≥80 years) diagnosed with Stage III and IV DLBCL from the Surveillance, Epidemiology, and End Results (SEER) 18 database. We calculated 1- and 2- year relative survival rates of the patients during 1992-1997 (Pre-rituximab era) and 1998-2009 (post –rituximab era). We also analyzed survival rates of patients diagnosed before (1998 – 2005) and after (2006-2009) FDA approval of rituximab for the first line treatment of DLBCL. We used SEER Stat software to calculate relative survival (RS) rates.
Results
There were 2709 advanced DLBCL patients reported during 1992-2009. Overall median survival of the group was 6±0.240 months. The 1- and 2- year relative survival rates of the patients improved significantly from pre-rituximab era to post-rituximab era (1 year RS: 30±2.0 vs 38.9±1.2; Z value 4.16 and 2 year RS: 19.7±1.8 vs 32.8±1.2; Z 5.16). The survival rates were higher in the post-rituximab era for all the cohorts except the Blacks and Others. However, there was no difference in the survival rates of the patients diagnosed during 2006-2009 compared to those diagnosed during 1998-2005 (Table).
Conclusion
Our population based study showed that the survival rates of very elderly patients with advanced DLBCL have improved in the post-rituximab era for all groups except the Blacks and Others. There is no significant improvement in survival of patients before- and after approval of rituximab in the post-rituximab era.
Abstract 2640. Table: Advanced DLBCL relative survival rates in elderly (age ≥ 80 years) Cohorts Survival 1992-1997 1998-2009 1998-2005 2006-2009 Z value (92-97 vs 98-09) Zvalue (98-05 vs 06-09) N RS ± SE% N RS ± SE% N RS ±SE % N RS ± SE% Male & Female 12 mo 633 30±2.0 2,076 38.9±1.2 1,274 38.1±1.5 802 40.1±1.9 4.159 0.796 24 mo 19.7±1.8 2,076 32.8±1.2 31.2±1.5 35.3±1.9 5.162 1.166 Male 12 mo 263 30.6±3.1 950 39.7±1.7 583 38.3±2.2 367 41.0±2.8 2.798 0.632 24 mo 18.6±2.7 950 33.7±1.8 30.6±2.2 38.4±3.0 3.750 1.304 Female 12 mo 370 29.5±2.5 1,126 38.2±1.5 691 37.4±2.0 435 39.4±2.5 3.036 0.478 24 mo 20.4±2.3 1,126 32.1±1.6 31.7±2.0 32.7±2.5 3.620 0.335 White 12 mo 572 29.8±2.0 1,786 39.8±1.3 1,101 38.5±1.6 685 41.8±2.0 4.145 1.106 24 mo 19.9±1.9 1,786 33.7±1.3 32.0±1.6 36.4±2.1 5.029 1.266 Black 12 mo 20 21.0±9.4 77 27.0±5.4 46 30.9±7.3 31 21.2±7.8 1.499 -1.030 24 mo 17.3±9.2 77 23.6±5.5 25.1±7.0 19.5±8.0 1.476 -0.894 Other 12 mo 41 36.1±7.8 211 35.4±3.5 126 36.3±4.5 85 34.1±5.4 0.349 0.029 24 mo 16.7±6.3 211 28.1±3.4 25.4±4.1 31.7±5.4 1.114 0.631
N: Number of patients

Disclosures
No relevant conflicts of interest to declare.