Hum Pathol. 2020 Aug 13. pii: S0046-8177(20)30150-7. [Epub ahead of print]
Acute myeloid leukemia with myelodysplasia-related changes (AML-MRC) generally confers poor prognosis; however, clinical outcome remains heterogeneous. We sought to further stratify this sub-entity of AML by performing a retrospective analysis of 179 adult AML-MRC patients diagnosed at our institution. Based on 2016 WHO diagnostic criteria, 44 (25%) had multilineage dysplasia alone (AML-MRC-M), 74 (41%) had history of MDS or MDS/MPN (AML-MRC-H), and 61 (34%) had MDS-related cytogenetics (AML-MRC-C). AML-MRC-M and hematopoietic stem cell transplantation (HSCT) were associated with prolonged EFS (P=0.0051 and P<0.0001, respectively) and OS (P=0.0015 and P<0.0001, respectively) while AML-MRC-C and age ≥60 years were associated with shorter EFS (P=0.028 and P=0.015, respectively) and OS (P=0.021 and P=0.013, respectively). Of note, NPM1mut did not affect patient outcome. Multivariable analysis confirmed HSCT and AML-MRC-C as independent predictors for EFS (P<0.0001 and P=0.0342, respectively) and OS (P<0.0001 and P=0.0295, respectively). AML-MRC-M was an independent predictor for OS (P=0.0449). When compared to a control group of 105 AML not otherwise specified with normal karyotype (NK-AML-NOS), AML-MRC-M patients had similar EFS and OS (P=0.99 and P=0.91, respectively). However, AML-MRC-H and AML-MRC-C were associated with shorter EFS and OS (P=0.0002 and P<0.0001, respectively) when compared to the same control group. In a subset of patients, NGS analysis showed AML-MRC-M was associated with ASXL1 mutation compared to NK-AML (56% vs 6%). In conclusion, AML-MRC-M demonstrates superior clinical outcome compared to the rest of AML-MRC. They have comparable outcome to NK-AML-NOS and this data suggests AML-MRC-M may be considered not to be classified in the same group as other AML-MRC patients.
Keywords: ASXL1 mutation; NPM1 mutation; acute myeloid leukemia; clinical outcome; multilineage dysplasia; myelodysplasia related changes