Pediatric AML (pAML) is characterized by the blockage of differentiation of myeloid elements and the accumulation of immature blasts that express myeloid lineage markers, including myeloperoxidase, non-specific esterase, CD11c, CD14, and CD64. Although the French-American-British (FAB) AML classification is still used, the World Health Organization (WHO) proposed an extended classification based on clinical, morphological, immunophenotypical, cytogenetic, and molecular characteristics.¹ At the initial diagnosis of AML, genomic profiling based on cytogenetics (karyotype and FISH), PCR-based methods, and targeted sequencing remains the gold standard.² Chromosomal abnormalities are detected in 75 to 80% of pAML cases and are important in diagnosis and an independent prognostic indicator. The most frequent cytogenetic abnormalities in pAML are balanced chromosomal rearrangements, leading to the formation of chimeric fusion genes, however, unbalanced abnormalities are less frequent in pAML compared to adult AML.^1,3 Mutation detection is also important in risk stratification, particularly in patients with normal karyotype. Furthermore, determining the mutation origin (germline vs. somatic) is important, especially considering the possibility of intrafamily donors for bone marrow transplantation, because a substantial number of pAML cases have underlying germline mutations.

The prognosis of pAML is significantly better than that of adult AML, likely due to the better prognostic genetic markers associated with pediatric patients.¹ For example, TP53 loss or mutation, a common poor marker in adult AML, is rarely seen in pAML. In addition, pAML is typically treated with more intensive chemotherapy regimens than adult AML due to the higher tolerance of children.