Racial and ethnic disparities in outcomes of diffuse large B cell lymphoma in adolescent and young adults: a SEER database analysis

Data regarding racial disparities in the incidence, treatment, and outcomes of diffuse large B-cell lymphoma (DLBCL) is limited in the adolescent and young adult (AYA) population. We utilized the surveillance, epidemiology, and end-result (SEER) registry research plus database to evaluate racial/ethnic disparities in 8605 AYA patients with DLBCL. Race/ethnicity was categorized into three main subsets: non-Hispanic Whites (NHW), non-Hispanic Blacks (NHB), and 'other races' that included Hispanics (H), American Indian/Alaskan Native (AI/AN), Asian or Pacific Islander (A/PI). NHB were more likely to present with advanced stage disease (p < 0.001) and B symptoms (p < 0.001) and were less likely to receive chemotherapy (p < 0.001) compared to non-Hispanic white (NHW) patients and other races respectively. NHB patients had inferior 5-year disease specific survival (DSS) (70% vs 85% vs 80%, p < 0.001) and 5-year overall survival (OS) (66% vs 82% vs 77%, p < 0.001) compared to NHW and other races respectively. Black race was independently associated with both inferior DSS (HR 1.55, 95% CI 1.17-2.05, p = 0.002) and OS (HR 1.41, 95% CI 1.10-1.83, p = 0.007) after adjusting for age, gender, stage, presence of B symptoms, receipt of chemotherapy and radiation. NHB-DLBCL patients also had a lower 1-year relative survival rate (RSR) compared to NHW and other races. The low RSR in NHB patients persisted up to 5 years from diagnosis unlike NHW and other races. Our study shows that despite significant therapeutic advances in DLBCL over the last two decades, NHB AYA patients with DLBCL continue to have inferior survival outcomes compared to other ethnic and racial groups with disparities arising as early as the first year of diagnosis.