Neutrophil elastase mutations and risk of leukaemia in severe congenital neutropenia

Summary Severe congenital neutropenia (SCN) is a heterogeneous bone marrow failure syndrome predisposing to myelodysplastic syndrome and acute myeloid leukaemia (MDS/AML). We studied 82 North American and Australian SCN patients enrolled in the Severe Chronic Neutropenia International Registry who were on long‐term treatment with granulocyte colony‐stimulating factor and for whom the neutrophil elastase (ELA2) gene was sequenced. There was no significant difference in the risk of MDS/AML in patients with mutant versus wild‐type ELA2: the respective cumulative incidences at 15 years were 36% and 25% (P = 0·96). Patients with either mutant or wild‐type ELA2 should be followed closely for leukaemic transformation.