Next-Generation Sequencing–Based Genomic Profiling of Children with Acute Myeloid Leukemia

Abstract

Pediatric acute myeloid leukemia (AML) represents a major cause of childhood leukemic mortality with only a limited number of studies investigating the molecular landscape of the disease. Here, we present an integrative analysis of cytogenetic and molecular profiles of 75 patients with pediatric AML from a multicentric, real-world patient cohort treated according to AML BFM protocols. Targeted next-generation sequencing (NGS) of 54 genes revealed 17 genes that were recurrently mutated in more than 5% of patients. Considerable differences were observed in the mutational profiles compared to previous studies as BCORL1, CUX1, KDM6A, PHF6 and STAG2 mutations were detected at a higher frequency than previously reported, whereas KIT, NRAS, and KRAS were less frequently mutated. Our study identified novel recurrent mutations at diagnosis in BCORL1 gene in 9% of the patients. Tumor suppressor gene (PHF6, TP53, WT1) mutations were found to be associated with induction failure and shorter event-free survival suggesting important roles of these alterations in resistance to therapy and disease progression. Comparison of the mutational landscape at diagnosis and relapse revealed an enrichment of mutations in tumor suppressor genes (16.2% vs. 44.4%) and transcription factors (35.1 vs. 55.6%) at relapse. Our findings shed further light on the heterogeneity of pediatric AML and identified previously unappreciated alterations that may lead to improved molecular characterization and risk stratification of pediatric AML.