Two case studies of chronic idiopathic neutropenia preceding acute myeloidleukaemia

Chronic idiopathic neutropenia is regarded as a benign disorder without ris k of malignant transformation, We present two patients with chronic idiopat hic neutropenia who showed disease progression to acute myeloid leukaemia. Sequence analysis of the granulocyte-colony stimulating factor receptor (G- CSFR) gene from leukaemic DNA did not reveal any mutations and microsatelli te analysis provided no evidence of microsatellite instability or loss of c onstitutional heterozygosity. These case studies suggest that chronic idiop athic neutropenia may constitute a preleukaemic condition in some patients. Alterations of the G-CSFR or defective DNA mismatch repair do not appear;t o be involved in malignant transformation.