Recent Progress in Chronic Neutrophilic Leukemia and Atypical Chronic Myeloid Leukemia

Purpose of Review: We reviewed recent diagnostic and therapeutic progress in chronic neutrophilic leukemia (CNL) and atypical chronic myeloid leukemia (aCML). We summarized recent genetic data that may guide future efforts towards implementing risk-adapted therapy based on mutational profile and improving disease control and survival of affected patients. Recent Findings: Recent genetic data in CNL and aCML prompted modifications to the World Health Organization (WHO) diagnostic criteria, which have improved our understanding of how CNL and aCML are different diseases despite sharing common findings of peripheral granulocytosis and marrow myeloid hyperplasia. The overlap of recurrently mutated genes between aCML and CMML support considering CSF3R-T618I mutated cases as a distinct entity, either as CNL or CNL with dysplasia. Ongoing preclinical and clinical studies will help to further inform the therapeutic approach to these diseases. Summary: Our understanding of CNL and aCML has greatly advanced over the last few years. This will improve clarity for the diagnosis of these diseases, provide a strategy for risk stratification, and guide risk-adapted therapy.