Superior outcomes with paediatric protocols in adolescents and young adults with aggressive B-cell non-Hodgkin lymphoma.

Survival disparities by locus of care (LOC; paediatric versus adult) among adolescents and young adults (AYA) with acute lymphoblastic leukaemia (ALL) are well documented. Whether similar disparities exist among AYA with aggressive mature B-cell non-Hodgkin lymphoma (B-NHL) is unknown. We identified all Ontario, Canada AYA aged 15-21 years at diagnosis of B-NHL between 1992 and 2012. Demographic, disease, treatment and outcome data were chart abstracted. The impact of LOC on event-free (EFS) and overall survival (OS) were determined, adjusted for patient and disease covariates. Among 176 AYA with B-NHL, 62 (35·2%) received therapy at paediatric centres. The 5-year EFS and OS [± standard error (SE)] for the overall cohort were 72·2 [3·4]% and 76·1 [3·2]% respectively. Both EFS and OS were superior among paediatric centre AYA [EFS (± SE) 82·2 (4·9)% vs. 66·7 (4·4)%, P = 0·02; OS 85·5 (4·5)% vs. 71·1 (4·3)%, P = 0·03]. Adjusted for histology, stage and time period, adult centre AYA had inferior EFS [hazard ratio (HR) 2·4, 95% confidence interval (CI) 1·1-4·9, P = 0·02] and OS (HR 2·5, 95% CI 1·1-5·7, P = 0·03). Sensitivity analyses restricted to the latest time period, when most adult centre AYA received rituximab, demonstrated similar disparities. Similar to AYA with ALL, AYA with B-NHL may benefit from being treated with paediatric protocols. Studies prospectively validating these results are warranted.