Trends in the improvement in survival among patients with diffuse large B-cell lymphoma (DLBCL).

Abstract

147 Background: Advances in treatment for patients with DLBCL have led to improved patient outcomes, but whether disparities exist with regards to improved survival outcomes remains understudied. We sought to describe changes in DLBCL survival rates over time and explore potential differential survival patterns by patients’ race and age. Methods: We utilized the Surveillance, Epidemiology, and End Results (SEER) database to identify patients diagnosed with DLBCL from 1980-2009 and determined 5-year survival rates for all patients, categorizing patients by year of diagnosis. We used descriptive statistics and logistic regression, adjusting for stage and year of diagnosis, to describe changes in 5-year survival rates over time by race/ethnicity and age. Results: We identified 43,564 patients with DLBCL eligible for this study (median age 67 years [ages: 18-64 = 44.2%, 65-79 = 37.1%, 80+ = 18.7%], 53% male, 40% stage III/IV). Most were White race (81.4%), followed by race/ethnic groups of Asian/Pacific Islander (API) (6.3%), Black (6.3%), Hispanic (5.4%), and American Indian/Alaska Native (AIAN) (0.05%). Overall, the 5-year survival rate improved from 35.1% in 1980 to 52.4% in 2009 across all patients (odds ratio (OR) for 5-year survival with increasing year of diagnosis = 1.05, p <.001). Patients in race/ethnic minority groups (API: OR = 0.86, p <.0001; Black: OR = 0.57, p <.0001; AIAN: OR = 0.51, p =.008) and older adults (ages 65-79: OR = 0.43, p <.0001; ages 80+: OR = 0.13, p <.0001) had worse 5-year survival rates adjusting for race, age, stage, and diagnosis year. We found consistent improvement in the odds of 5-year survival for year of diagnosis across all race and ethnicity groups (White: OR = 1.05, p <.001; API: OR = 1.04, p <.001; Black: OR = 1.06, p <.001; Hispanic: OR = 1.05, p <.005; AIAN: OR = 1.05, p <.001) and age groups (ages 18-64: OR = 1.06, p <.001; ages 65-79: OR = 1.04, p <.001; ages 80+: OR = 1.04, p <.001). Conclusions: In this analysis of SEER data, we found that patients with DLBCL experienced improvements in 5-year survival rates from 1980 to 2009, despite ongoing disparities demonstrating worse survival among patients in race/ethnic minority groups and older adults. Notably, we did not find differential improvement in the odds of 5-year survival within subgroups of race and age, underscoring the need for ongoing investigations to address disparities in cancer care delivery and outcomes.