Clonality of chronic neutrophilic leukaemia associated with myeloma: analysis using the X-linked probe M27 beta.

AIMS

To determine whether myeloid proliferation was monoclonal or polyclonal in a woman with chronic neutrophilic leukaemia and myeloma.

METHODS

The X-linked probe, M27 beta was used to determine the clonality of the neutrophil population by analysis of restriction fragment length polymorphisms and X inactivation pattern.

RESULTS

A polyclonal pattern of X inactivation was obtained for the neutrophil population in this patient.

CONCLUSION

The myeloid expansion in chronic neutrophilic leukaemia associated with myeloma represents a polyclonal reactive response to the plasma cell clone rather than a co-existent myeloproliferative disorder.