Impact of Genomic and Clinical Factors on Outcome of Children =18 Months of Age with INSS Stage 3 Neuroblastoma with Unfavorable Histology without MYCN Amplification

Patients with INSS stage 3, MYCN–non-amplified, unfavorable histology neuroblastoma represent a rare subset of children with outcomes that are inferior to those of most patients with advanced locoregional disease, and superior to those of most high-risk patients. We evaluated the impact of clinical variables on outcome and used available tumor samples from subjects within this subgroup to correlate whole exome sequencing (WES) and RNA sequencing (RNASeq) profiles with outcome. We found that subjects with tumors harboring chromosome 11q losses had inferior outcomes and describe an expression profile with universally favorable outcomes. These findings provide a framework for a refined risk stratification where patients with 11q loss could be included with traditional high-risk groups and patients with a favorable expression profile could be considered to have non-high-risk disease. Overall design: Patients enrolled on Children's Oncology Group (COG) protocols A3973 (n=34) and ANBL0532 (n=27), and/or biology protocol ANBL00B1 (n=72) were analyzed. Tumors with available DNA (n=65) and RNA (n=42) were subjected to whole exome sequencing (WES) and RNAseq. WES analyses and gene expression profiling were evaluated for their impact on survival. Multivariate analyses of EFS and OS using significant factors from univariate analyses were performed.