Presence of the bcr/abl rearrangement in a patient with chronic neutrophilic leukaemia.

An 83 year old women presented with a myeloproliferative disorder involving the myeloid and megakaryocytic lines, and characterised by mature neutrophil leucocytosis. There was a high/normal neutrophil alkaline phosphatase activity and absence of the Philadelphia chromosome, features compatible with a diagnosis of chronic neutrophilic leukaemia (CNL). Southern blot analysis of the patient's DNA revealed the presence of the bcr/abl rearrangement. Combined with a previous report of detection of Ph1 chromosome in long term bone marrow cultures in a patient with CNL, this finding suggests that the bcr/abl hybrid gene might occasionally result in a myeloproliferative disorder with a phenotype closely resembling that of CNL.