Survival Trends Among Very Elderly Patients with Advanced Diffuse Large B-Cell Lymphoma - a Population Based Study

Abstract

BackgroundRituximab 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.MethodsWe 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.ResultsThere 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).ConclusionOur 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)CohortsSurvival1992-19971998-20091998-20052006-2009Z value (92-97 vs 98-09)Zvalue (98-05 vs 06-09)NRS ± SE%NRS ± SE%NRS ±SE %NRS ± SE%Male & Female12 mo63330±2.02,07638.9±1.21,27438.1±1.580240.1±1.94.1590.79624 mo19.7±1.82,07632.8±1.231.2±1.535.3±1.95.1621.166Male12 mo26330.6±3.195039.7±1.758338.3±2.236741.0±2.82.7980.63224 mo18.6±2.795033.7±1.830.6±2.238.4±3.03.7501.304Female12 mo37029.5±2.51,12638.2±1.569137.4±2.043539.4±2.53.0360.47824 mo20.4±2.31,12632.1±1.631.7±2.032.7±2.53.6200.335White12 mo57229.8±2.01,78639.8±1.31,10138.5±1.668541.8±2.04.1451.10624 mo19.9±1.91,78633.7±1.332.0±1.636.4±2.15.0291.266Black12 mo2021.0±9.47727.0±5.44630.9±7.33121.2±7.81.499-1.03024 mo17.3±9.27723.6±5.525.1±7.019.5±8.01.476-0.894Other12 mo4136.1±7.821135.4±3.512636.3±4.58534.1±5.40.3490.02924 mo16.7±6.321128.1±3.425.4±4.131.7±5.41.1140.631 NNumber of patients DisclosuresNo relevant conflicts of interest to declare.