Impact of Body Mass Index at Diagnosis on Outcomes of Pediatric Stage III and IV Mature B-Cell Non- Hodgkin Lymphomas at South Egypt Cancer Institute: A Prospective Cohort Study.

Background and aim of the study: Nutritional status impacts treatment
outcomes in pediatric cancers. This study evaluated the impact of body mass
index (BMI) on clinical outcomes and survival in children with stage III and IV
mature B-cell non-Hodgkin lymphomas (B-NHL).
Methods: A prospective cohort study enrolled pediatric patients with advanced
CD20-positive mature B-NHL at South Egypt Cancer Institute (SECI), Assiut
University from 2020-2025. Patients were risk-stratified by the BFM-95
protocol and categorized by BMI. Treatment response (at the end of treatment),
event-free survival (EFS), and overall survival (OS) were assessed.
Results: A total of 65 newly diagnosed pediatric patients with stage III and IV
mature B-cell NHL were enrolled in the study. The mean age was 7.35 ± 3.9
years (median 6 years) with a male predominance (75.4%). Patients with stage
III disease were (69.2%), and 58.4% were classified in the highest risk group
(R4). The average BMI was 16.51 ± 2.9 kg/m², with nearly half (49.2%) being
of normal weight while undernutrition was identified in 44.7% of cases.
Multivariate analysis revealed that each unit increase in BMI was independently
associated with a 21% reduction in the hazard of mortality, while it had
insignificant effect on OS in univariate analysis as while as EFS.
Conclusions: These findings suggest that BMI is a significant prognostic factor
in stage III and IV pediatric mature B-cell lymphomas and should be considered
during risk stratification and supportive care planning. Improved nutritional
status appears linked to better treatment tolerance and survival outcomes in this
aggressive malignancy.