Uncommon Cytogenetic Abnormalities Identifying High-Risk Acute Myeloid Leukemia in Children

Abstract

Pediatric acute myeloid leukemia (AML) represents an aggressive disease and is the leading cause of childhood leukemic mortality. The genomic landscape of pediatric AML has been recently mapped and redefined thanks to large-scale sequencing efforts. Today, understanding how to incorporate the growing list of genetic lesions into a risk stratification algorithm for pediatric AML is increasingly challenging given the uncertainty regarding the prognostic impact of rare lesions. Here we review some uncommon cytogenetic lesions to be considered for inclusion in the high-risk groups of the next pediatric AML treatment protocols. We describe their main clinical characteristics, biological background and outcome. We also provide some suggestions for the management of these rare but challenging patients and some novel targeted therapeutic options.

High-Risk Acute Myeloid Leukemia: A Pediatric Prospective

“…In contrast, NUP98-NSD1 can be found in 3.8% cases of pediatric AML and is the most frequent NUP98 rearrangement. It is usually associated with other chromosomal abnormalities, particularly trisomy 8, and other genetic mutations, such as FLT3-ITD, WT1, and CEBPA, and appears to play a role in histone methylation and acetylation [ 22 ].…”

Exploiting Clonal Evolution to Improve the Diagnosis and Treatment Efficacy Prediction in Pediatric AML

“…This subtype of AML is highly peculiar and does not belong to any additional category, and its remission rates are >95% and overall survival is >80% [10], thanks to a target therapy consisting of all-trans-retinoic acid (ATRA) associated with arsenic trioxide (ATO), with the addition of the anti-CD33 gemtuzumabozogamicin in high-risk patients, defined as having WBC prior to treatment ≥10 × 109/L [9]. Other subtypes of pediatric AML, characterized by a favorable prognosis, are those involving core binding factor (CBF), accounting for approximately 20-25% of pediatric Other subtypes of pediatric AML, characterized by a favorable prognosis, are those involving core binding factor (CBF), accounting for approximately 20-25% of pediatric AML cases [11], such as t(8;21) (q22;q22) and inv (16),which lead to the fusion genes RUNX1-RUNX1T1 and CBFB-MYH11, respectively.…”

“…It represents a subgroup of pediatric AML with intermediate/unfavorable prognosis and for this reason, many specific drugs are in preclinical and clinical trials [ 14 ]. A subtype of pediatric AML with an unfavorable prognosis is that characterized by the fusion gene CBFA2T3-GLIS2 , caused by inv(16) (p13.3q24.3), which is present in 15–20% of pediatric non-Down syndrome acute megakaryoblastic leukemia (non-DS-AMKL) and about 7–8% of pediatric AML with normal karyotype [ 15 , 16 ], mostly found in infant patients (<3 years) [ 17 , 18 ]. AMKL occurs particularly in children with Down syndrome, however, in contrast to DS-AMKL which display 80% of overall survival rate, non-DS-AMKL is associated with extremely poor prognosis [ 19 , 20 ].…”

“…The concept of clonal evolution in cancer, which was first conceived in 1976 [ 28 ], appears to apply also to AML, as demonstrated by the pivotal work of Ding et al [ 29 ] in adult AML and also confirmed in the pediatric setting [ 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 ]. This term refers to the selection and expansion, over the course of the disease, of subclones that originate from a common ancestral clone but acquire different mutations that confer them a survival advantage, leading to genetic diversity within a cell lineage [ 2 ].…”