Treatment Outcome and Prognostic Factors in Children and Adolescents with Relapsed and Refractory Classic Hodgkin Lymphoma...

Background: Children with Hodgkin lymphoma (HL) achieve high cure rate 
around 80%, while 20% will ultimately relapse. Identifying reliable risk 
factors to guide treatment plans at relapse is essential. The purpose of this 
study is to evaluate the outcome and prognostic factors that affect the 
outcome of pediatric patients with relapsed and refractory classic HL.
Methods: A retrospective descriptive cohort study included all patients with 
relapsed and refractory classic HL at the Children's Cancer Hospital of Egypt 
(CCHE-57357) from July 2007 to December 2018.
Results: One hundred twenty-nine patients were eligible for the study. Male 
to female ratio was 1.9:1. The median age at relapse was 10.5 years. Time to 
relapse, stage at relapse, and response to salvage chemotherapy, all had a 
significant impact on survival outcomes. Overall survival (OS) and event-free 
survival (EFS) were 38.3% and 25% for those with refractory disease, while 
for early relapse were 68.0% and 49.6%, and 91.2% and 58.3% for those with 
late relapse, with p values of 0.001 and 0.001, respectively. At relapse, stage I 
patients had 100% OS and EFS and declined to 80% and 59.3%, respectively 
for stage II and 81.7% and 42.3% for stage III. The lowest OS and ES was 
observed in stage IV disease standing for 68% and 34.5%, respectively, with 
statistically significant differences for both OS and EFS (P values of 0.001). 
Patients who achieved negative positron emission tomography-computed 
tomography (PET-CT) after 2 cycles had OS and EFS of 91% and 70.1%, 
compared to 70% and 29.3% for those with positive PET-CT (p = 0.001 for 
both). Multivariate analysis identified two predictors of lower EFS: time to 
relapse and PET-CT response after salvage therapy. The 5-year OS and EFS 
rates for the cohort were 76% and 48.1%, respectively
Conclusions: The prognostic factors that have the most significant impact on 
the survival outcome of pediatric patients with relapsed and refractory classic 
HL are the time to relapse, and PET CT response after 2 cycles.