Higher tumor mutational burden is associated with inferior outcomes among pediatric patients with neuroblastoma.

Abstract

Neuroblastoma is a pediatric malignancy with heterogeneous clinical outcomes. Our aim was to identify prognostic genetic markers for patients with neuroblastoma, who were treated with the Taiwan Pediatric Oncology Group (TPOG) neuroblastoma N2002 protocol, to improve risk stratification and inform treatment. Our analysis was based on 53 primary neuroblastoma specimens, diagnosed pre-chemotherapy, and 11 paired tumor relapse specimens. Deep sequencing of 113 target genes was performed using a custom panel. Multiplex ligation-dependent probe amplification was performed to identify clinical outcomes related to copy-number variations. We identified 128 variations associated with survival, with the number of variations being higher in the relapse than that in the diagnostic specimen (p=.03). The risk of event and mortality was higher among patients with a tumor mutational burden ≥10 than that in patients with a lower burden (p<.0001). Multivariate analysis identified tumor mutational burden, MYCN amplification, and chromosome 3p deletion as significant prognostic factors, independent of age at diagnosis, sex, and tumor stage. The 5-year event-free survival and overall survival rate was lower among patients with high tumor burden than in patients with low tumor burden. Furthermore, there was no survival of patients with an ALK F1147L variation at 5 years after diagnosis. Genome sequencing to determine the tumor mutational burden and ALK variations can improve the risk classification of neuroblastoma and inform treatment.