The presence of circulating plasma cells in patients with multiple myeloma is considered as a marker for highly proliferative disease and associated with a worse prognosis.

Plasma cell counting is conventionally done by means of peripheral blood film morphology using light microscopy. However, this manual method is laborious as well as imprecise due to the low number of cells counted, and inter-observer variability. Flow cytometry with monoclonal antibodies is unsuitable as a screening test. The procedure is not automated, and it is expensive and time consuming. Therefore, new rapid, effective and inexepensive methods are needed for risk-stratification in patients with multiple myeloma.

Automated antibody-synthesizing or secreting cells counting from routine haematology systems (XN-1000/20) without sample preparation and in less than 1 minute will further reduce the workload in haematology laboratories and it can be used for counting circulating plasma cells in peripheral blood in patients with multiple myeloma.