Comprehensive genomic profiling
CGP was performed using either FoundationOne® CDx or FoundationOne® Heme oncopanels (Foundation Medicine, Inc., Cambridge, MA, USA). Both are clinical-grade Clinical Laboratory Improvement Amendments (CLIA)-approved next-generation sequencing tests. FoundationOne® CDx interrogates 324 genes for single nucleotide variants, copy number alterations, indels, gene arrangements, tumor mutation burden (TMB), and microsatellite status (Table S1), while FoundationOne® Heme interrogates 406 genes and selected introns of 31 genes involved in rearrangements. Additionally, FoundationOne® Heme interrogates the RNA of 265 genes commonly rearranged in cancer to better identify known and novel gene fusions (Table S2). Therefore, FoundationOne® Heme is a more effective assay for pediatric patients with hematologic malignancies, sarcoma, and other solid tumors.