Background: Telomerase activity is associated with most malignant tumors. The aim of this trial was to evaluate telomerase activity in multiple myeloma including prognostic potential of this marker. Design andsubject: We háve investigated tne prognostic significance of telomerase activity in multiple myeloma. CD 138+ myeloma cells were isolated from bone marrow of 130 patients with active multiple myeloma. Ten patients with monoclonal gammopathy of undertermined significance represent control group with low activity of disease. The analyses of telomerase activity were undertaken only on 34 samples with high purity of CD 138+ myeloma cells with medián 95,5 % (range 50,0-100,0%). There was heterogeneity in telomerase activity. Index for telomerase activity in multiple myeloma patients was 0.92 for CD138+ MM cells and 0.68 for CD138- cells (p=0,238). The corresponding indexes for newly diagnosed multiple myeloma and relapse only were 1.18 (CD138+) and 0.81 (CDÍ38-). In control group of monoclonal gammopathy of undertermined significance, the telomerase activity index (0.20) was markedly lower in comparison with the multiple myeloma patients (p=0,054), with very low activity of telomerase activity detectable in 2 of 10 patients only. No significant correlations with standard prognostic factors were observed. Similar was true for parameters of survival. Conclusion: The results háve shown that telomerase activity has a trend to correlate with activity of multiple myeloma. Unfortunately telomerase activity in marrow of multiple myeloma patients is not specific for CD138+ myeloma cells. This fact limits usefulness of telomerase activity for prognostic purpose in this diagnosis.

        Key words: multiple myeloma, prognosis, telomerase, telomerase activity