CSF3R and chronic neutrophilic leukemia: In 2014, Tefferi et al. (5,6) proposed a revision ofthe WHO criteria, which included major and minor changes in the diagnosis of CNL, suchas i) a peripheral blood leukocyte level ≥13×109/L,ii) a peripheral blood neutrophil/band percentage distribution>80%, and iii) the presence of a CSF3R T618Imutation or other membrane proximal CSF3R mutation.