Klin Onkol 2008; 21(Suppl 1): 254-257.
Backgrounds: Multicolor fl ow cytometry is a sensitive tool for the analysis of plasma cell population. It can differentiate between normal and malignant plasma cells and enables their quantifi cation.
Design and Subjects: We have used fl ow cytometry for quantifi cation and immunophenotyping of plasma cells from 25 patients with monoclonal gammopathy of undetermined signifi cance and 78 those with multiple myeloma aiming to identify and characterize markers that distinguish between the two conditions.
Methods and Results: The expression of surface antigens CD38, CD138, CD45, CD56 and CD19 was analysed on bone marrow plasma cells.
As compared to MM patients, MGUS patients had higher proportion of residual CD19+ plasma cells (p<0,001) and lower counts of pathologic CD56+ plasma cells (p=0,004) in the bone marrow.
Conclusions: The number of CD19+ plasma cells appeared to be an unequivocal marker that distinguishes monoclonal gammopathy of unknown signifi cance from all stages of multiple myeloma. Immunophenotyping of plasma cell can thus contribute to the differential diagnosis of both diseases. It has also been suggested that flow cytometric analysis should be useful for prognostic evaluation and for the study of minimal residual disease.
