Blood Adv. 2024 Apr 15. pii: bloodadvances.2023011771. [Epub ahead of print]
Romy Elise van Weelderen,
Christine J Harrison,
Kim Klein,
Yilin Jiang,
Jonas Abrahamsson,
Todd Alonzo,
Richard Aplenc,
Nira Arad-Cohen,
Emmanuelle Bart-Delabesse,
Barbara Buldini,
Barbara De Moerloose,
Michael N Dworzak,
Sarah Elitzur,
José M Fernández Navarro,
Alan S Gamis,
Robert B Gerbing,
Bianca F Goemans,
Hester A de Groot-Kruseman,
Erin M Guest,
Shau Yin Ha,
Henrik Hasle,
Charikleia Kelaidi,
Helene Lapillonne,
Guy Leverger,
Franco Locatelli,
Takako Miyamura,
Ulrika Noren-Nystrom,
Sophia Polychronopoulou,
Mareike Rasche,
Jeffrey E Rubnitz,
Jan Stary,
Anne Tierens,
Daisuke Tomizawa,
Michel C Zwaan,
Gertjan J L Kaspers.
Comprehensive international consensus on cytogenetic risk-group stratification of KMT2A-rearranged (KMT2A-r) pediatric acute myeloid leukemia (AML) is lacking. This retrospective (2005-2016) International Berlin-Frankfurt-Münster Study Group study on 1,256 children with KMT2A-r AML aimed to validate the prognostic value of established recurring KMT2A fusions and additional cytogenetic aberrations (ACAs), and secondly, to define additional, recurring KMT2A fusions and ACAs, evaluating their prognostic relevance. Compared to our previous study, three additional, recurring KMT2A-r groups were defined: Xq24/KMT2A::SEPT6, 1p32/KMT2A::EPS15, 17q12/t(11;17)(q23;q12). Across 13 KMT2A-r groups, 5-year event-free survival probabilities varied significantly (21.8% to 76.2%; P<0.01). ACAs occurred in 46.8% of 1,200 patients with complete karyotypes, correlating with inferior overall survival (56.8% vs 67.9%; P<0.01). Multivariable analyses confirmed independent associations of 4q21/KMT2A::AFF1, 6q27/KMT2A::AFDN, 10p12/KMT2A::MLLT10, 10p11.2/KMT2A::ABI1, and 19p13.3/KMT2A::MLLT1 with adverse outcomes, but not those of 1q21/KMT2A::MLLT11 and trisomy 19 with favorable and adverse outcomes, respectively. Newly identified ACAs with independent adverse prognoses were monosomy 10, trisomies 1, 6, 16, and X, add(12p), and del(9q). Among patients with 9p22/KMT2A::MLLT3, the independent association of French-American-British-type M5 with favorable outcome was confirmed, and those of trisomy 6 and measurable residual disease at end of induction with adverse outcomes were identified. We provide evidence to incorporate the five adverse-risk KMT2A fusions into the cytogenetic risk-group stratification of KMT2A-r pediatric AML, to revise the favorable-risk classification of 1q21/KMT2A::MLLT11 to intermediate risk, and to refine risk-stratification of 9p22/KMT2A::MLLT3 AML. Future studies should validate the associations between the newly identified ACAs and outcome, and unravel the underlying biological pathogenesis of KMT2A fusions and ACAs.