CEBPA and acute myeloid leukemia: The ELN classification was then modified in 2017 by combining two intermediate groups into one, recommending mutation analysis to be performed in all patients, not only those with cytogenetically normal AML (CN-AML), considering only biallelic CEBPA mutations as prognostically favorable, requiring determination of high and low allelic ratios for internal tandem duplications of FLT3 (FLT3-ITD), and adding ASXL1, RUNX1 and TP53 mutations as adverse-risk markers [25].