European LeukemiaNet 2017 risk stratification for acute myeloid leukemia: validation in a risk-adapted protocol

Abstract

The 2017 European LeukemiaNet (ELN 2017) guidelines for the diagnosis and management of acute myeloid leukemia (AML) have become fundamental guidelines to assess the prognosis and post-remission therapy of patients. However, they have been retrospectively validated in few studies with patients included in different treatment protocols. We analyzed 861 patients included in the CETLAM-12 risk-adapted protocol, which indicates cytarabine-based consolidation for patients allocated to the ELN 2017 favorable-risk group, while it recommends allogeneic stem cell transplantation as a post-remission strategy for the ELN 2017 intermediate- and adverse-risk groups. We retrospectively classified patients according to the ELN 2017, with 327 (48%), 109 (16%) and 245 (36%) patients allocated to the favorable, intermediate and adverse risk group, respectively. The 2 and 5 year-overall survival (OS) were 77 and 70% for favorable risk patients, 52 and 46% for intermediate risk patients, and 33 and 23% for adverse risk patients, respectively. Furthermore, we identified a subgroup of patients within the adverse group (inv(3)/t(3;3), complex karyotype and/or TP53 mutation/17p abnormality) with a particularly poor outcome, with a 2-year OS of 15%. Our study validates the ELN 2017 risk stratification in a large cohort of patients treated with an ELN-2017 risk-adapted protocol, based on alloSCT after remission for non-favorable ELN subgroups, and identifies a genetic subset with a very poor outcome which warrants investigation of novel strategies.