Haematological and renal toxicity of radiation therapy in neuroblastoma paediatric patients

Purpose The objective of this study was to evaluate the renal and hematologic toxicity in paediatric patients with adrenal high-risk neuroblastoma who have received radiation therapy (RT) as part of radical treatment. Material and methods Pediatric patients diagnosed with high-risk adrenal neuroblastoma who received RT as part of the definitive treatment between January 2004 and May 2020 in a single institution were selected. Complete blood counts (CBC) and creatinine clearance (CrCl) pre-RT and post-RT were compared through the Wilcoxon signed-rank test and correlated with survival analysis by Cox regression. Results Forty-two children with a median age of 3 years at diagnosis and 2.8 years of follow-up were selected. A significant and acute decrease in lymphocytes was found ( p = 0.002) 1 month from RT. Patients with a drop higher than 50% of the previous value experimented a significant reduction in overall survival (55 vs 10%; p = 0.031). At the end of the follow-up, a significant increase in all blood counts was observed. With respect to renal function, an acute and significant decrease in CrCl was observed tin patients younger than 4 years who received RT ( p = 0.013). However, it was not clinically relevant. Conclusion Our data suggest that acute lymphopenia occurs after RT and could be associated with a poorer prognosis. Other blood counts are reduced after RT and all of them are in physiological range at the end of follow-up. Our cohort presented excellent renal outcomes without any case of chronic renal dysfunction.