Heterogeneous cytogenetic subgroups and outcomes in childhood acute megakaryoblastic leukemia: a retrospective international study

Inaba et al (2015) Blood                                                               

Link to abstract: http://www.bloodjournal.org/content/126/13/1575

This international retrospective study (including COG, St Jude’s, and BFM data) included 490 patients (age ≤18 years) with non–Down syndrome AMKL diagnosed from 1989 to 2009. This AML subtype occurred in 7.8% of pediatric AML. Five-year event-free (EFS) and overall survival (OS) were 49.0% ± 2.7% in the cohort from 2000 to 2009 - significantly lower than for other AML subtypes. It was noted that patients treated in 2000 to 2009 received higher cytarabine doses and had better EFS and OS than those diagnosed in 1989 to 1999. The authors classified AMKL into 3 risk groups based on cytogenetics:

  • Good risk—7p abnormalities (5 year EFS 74%, 5 year OS 77%)
  • Intermediate risk—others including t(1;22)(p13;q13)/OTT-MAL (RBM15-MKL1) and 11q23/MLL except t(9;11). (5 year EFS 50%, 5 year OS 56%)
  • Poor risk—normal karyotypes, –7, 9p abnormalities including t(9;11)(p22;q23)/MLL-MLLT3, –13/13q-, and –15 (5 year EFS 22%, 5 year OS 24%)

*This risk stratification might help tailor treatments to each subgroup better.