Survival by Race and Ethnicity in Pediatric and Adolescent Patients With Hodgkin Lymphoma: A Children's Oncology Group Study.

Abstract

Population-based studies of children and adolescents with Hodgkin lymphoma (HL) report a survival disadvantage in nonwhite-non-Hispanic black (NHB) and Hispanic-patients. Whether disparities persist after adjustment for clinical and treatment-related variables is unknown. We examined survival by race/ethnicity in children receiving risk-based, response-adapted, combined-modality therapy for HL in contemporary Children's Oncology Group trials. This pooled analysis used individual-level data from 1,605 patients (younger than age 1 to 21 years) enrolled in phase III trials for low-risk (AHOD0431), intermediate-risk (AHOD0031), and high-risk (AHOD0831) HL from 2002 to 2012. Event-free survival (EFS) and overall survival (OS) were compared between non-Hispanic white (NHW) and nonwhite patients. Cox proportional hazards for survival were estimated for both de novo and relapsed HL, adjusting for demographics, disease characteristics, and therapy. At median follow up of 6.9 years, cumulative incidence of relapse was 17%. Unadjusted 5-year EFS and OS were 83% (SE, 1.2%) and 97% (SE, < 1%), respectively. Neither differed by race/ethnicity. In multivariable analyses for OS, nonwhite patients had a 1.88× higher hazard of death (95% CI, 1.1 to 3.3). Five-year postrelapse survival probabilities by race were as follows: NHW, 90%; NHB, 66%; and Hispanic, 80% (<i>P</i> < .01). Compared with NHW, Hispanic and NHB children had 2.7-fold (95% CI, 1.2 to 6.2) and 3.5-fold (95% CI, 1.5 to 8.2) higher hazard of postrelapse mortality, respectively. In patients who were treated for de novo HL in contemporary Children's Oncology Group trials, EFS did not differ by race/ethnicity; however, adjusted OS was significantly worse in nonwhite patients, a finding driven by increased postrelapse mortality in this population. Additional studies examining treatment and survival disparities after relapse are warranted.