Аннотация
Background.Multiple myeloma (MM) is a heterogeneous hematologic malignancy with variable clinical course and response to therapy [1,2]. Unfortunately, MM is still an incurable disease, and the difference in overallsurvival(OS) and progressive free surviva l (PFS) rates in patients varies depending on the risk group. Due to the limited access to high-tech molecular genetic studies for risk group stratification, it remains relevant to study more accessible prognostic markers, in particular based on flow cytometry data [1,8].Aim.In our study, our goal was to evaluate the level of CD56 expression on pathological plasma cells and their effect on the frequency of objective response to induction therapy and overall survival rates in patients with newly diagnosed MM.Materials and Methods.We conducted a retrospective single-center analysis of 26 newly diagnosed MM patients treated at the National Research Oncology Center in Astana, Kazakhstan. For immunophenotyping of plasma cells, we employed multicolor flow cytometry following the standardized EuroFlow protocol with its recommended antibody panels[7,17]. Only patients with ≥10% clonal plasma cells and an aberrant immunophenotype were included, in accordance with international recommendations [4,7,13]. Patients were stratified according to CD56 expression level. All patients received VCD induction therapy. Response was evaluated according to IMWG criteria, and OS was analyzed using Kaplan–Meier curves [3,11]. Results.High objective response rates and 100% overall survival at 24 months were observed in patients with CD56 expression ≤30%, while patients with negative CD56 expression and those with CD56 expression >30% were more likely to experience primary refractoriness and a tendency toward lower overall survival. However, in our study, the differences did not reach statistical significance (p=0.31), possibly due to the limited patient sample, but we do see a trend toward worse outcomes.Conclusion.CD56 expression is an accessible additional prognostic marker and may be used for treatment personalization in patients with multiple myeloma.Keywords:multiple myeloma, CD56, flow cytometry, immunophenotyping, prognosis.