Background. The aim of this study was to evaluate significance of CD 38++45-54+, CD 38++45-56+ and CD
38++45-138+ cells counts in peripheral blood of patients with multiple myeloma for monitoring of the minimal
Methods and Results. A triple-color flow cytometric analysis was used for this purpose. Peripheral blood of
29 patients with multiple myeloma who underwent high dose chemotherapy and autologous stem cells transplantation
was repeatedly analysed. Counts of myeloma cells in peripheral blood were compared to serum monoclonal
immunoglobulin concentration, serum calcium level, serum C - reactive protein, serum b2microglobulin, and number
of myeloma cells in bone marrow (morphology). From 29 patients in this study, 5 patients have relapsed. Patients
in relapse had significantly higher counts of CD 38++45-54+, CD 38++45-56+ and CD 38++45-138+ cells in
peripheral blood than patients in remission (geometrical average: 12,41; 6,20; 14,45 cells/ ml versus 4,08; 2,87; 2,58
cells/ml). The number of these cells correlated well with serum monoclonal immunoglobulin level and counts of
myeloma cells in bone marrow.
Conclusion. The authors conclude that the longitudinal multi-color flow cytometric analysis of CD 38++45-54+,
CD 38++45-56+ and CD 38++45-138+ cells in peripheral blood of patients with multiple myeloma is a useful method
for evaluation of the disease activity. Significance of peripheral myeloma cells count for prediction of the relapse
of the multiple myeloma remains to be evaluated.
minimal residual disease, multiple myeloma, flow cytometry.