TY - JOUR T1 - Chronic neutrophilic leukaemia JF - Journal of Clinical Pathology JO - J Clin Pathol SP - 680 LP - 684 DO - 10.1136/jclinpath-2015-203060 VL - 68 IS - 9 AU - Guldeep Uppal AU - Jerald Gong Y1 - 2015/09/01 UR - http://jcp.bmj.com/content/68/9/680.abstract N2 - Chronic neutrophilic leukaemia (CNL) is a rare type of myeloproliferative neoplasm (MPN) characterised by sustained leucocytosis (≥25×109/L) with neoplastic proliferation of neutrophilic granulocytes in blood and bone marrow. In contrast to chronic myeloid leukaemia, the disease primarily involves neutrophilic lineage with persistent proliferation of mature forms of neutrophils. No consistent cytogenetic changes have been reported. Known recurrent genetic changes in other MPNs such as JAK2, MPL, CALR, BCR-ABL1, PDGFRA, PDGFRB and FGFR1 are mostly absent. Recently, mutations in colony stimulating factor 3 receptor (CSF3R) have been reported in high frequency in CNL. This discovery has provided more insight into its pathogenesis and opened up possible treatment options. In this article, we review the clinical findings, morphology, pathobiology and differential diagnosis of CNL and treatment implications of CSF3R mutations. ER -