Introduction

Multiple myeloma is a myeloproliferative disease of complex pathogenesis which is represented by a plasma cells compartment developing into the so-called tumour mass as well as osteoclast cells together with their initial forms, precursors, affecting the skeletal system. Both disease processes are closely related with each other through the influence of cytokines and interactions among plasma cells, osteoclasts and bone marrow stromal cells. Nevertheless, there is often a disproportion between the bone disease and proliferation of plasma cells. The aim of this study was to identify the precursors of osteoclasts by cytofluorimetry in the blood and bone marrow samples from patients with multiple myeloma. We also analyzed the dependence between subpopulations of mononuclear cells in the blood and bone marrow. We tried to refer our results to the development of the disease and destruction of the skeletal system.

Materials and methods

An immunophenotype analysis was carried out on cells of 14 patients with de novo multiple myeloma by a three-colour cytofluorimetry FACS Calibur.

Results

The percentage of neoplastic cells in the bone marrow was 8.1–21.3 (average 13.8±6.12) whereas that in the blood was 0.1–3.6 (average 0.45±0.94). The percentage of precursors of osteoclasts in the bone marrow was 0.955±0.572 whereas that in the blood was 0.454±0.972. Our analysis showed a negative correlation between the percentage of preosteoclasts in the bone marrow and the para-meters of the erythrocytic system and the number of platelets. We also noticed a positive correlation between the percentage of preosteoclasts in the blood and the percentage of plasma cells in the bone marrow.

Conclusions

Immunological markers of multiple myeloma activity correspond to the disease activity and correlate with the number of preosteoclasts. A high percentage of preosteoclasts in the blood is connected with a low destruction of bones which suggests that a fewer number of osteoclasts destroy the skeletal system.