Objective: To assess the outcome of the measurement of apoptotic index in myeloma patients treated by conventional chemotherapy and novel drugs with biological mechanism of action, thalidomide and bortezomib.
Patients and methods: In a cohort of 189 patients with newly diagnosed multiple myeloma from November 1997 through February 2008, we assessed the prognostic significance of plasma cell apoptotic index (PC-AI) using annexin-V. The whole group was subsequently divided according to treatment approach (conventional chemotherapy only vs. inclusion of novel drugs, thalidomide and bortezomib), and curves of overall survival were constructed.
Results: In the whole group (n = 189), low levels of PC-AI <4.5% significantly separated patients with unfavorable prognosis (median OS 16 vs. 38 months, P = 0.004). In patients treated with conventional chemotherapy only (n = 139) the results were similar (median OS 10 vs. 25 months, P = 0.02), and the apoptotic index maintained its significance even within the group of 50 patients treated also with novel drugs (median OS 30 vs. 54 months, P = 0.027). PC-AI was found to be independent on both Durie-Salmon staging system and the International Prognostic Index.
Conclusion: Presented results suggest the use of apoptotic index by flow cytometry measurement as a fast and accessible method for prognostic stratification of myeloma patients in routine practice.