[Immuno Phenotypic Characteristics of Bone Marrow Monocytes and Its Clinical Significance in Patients with Multiple Myeloma].

Objective: To explore the characteristics of the immunophenotypic expression of bone marrow monocytes (M) and its clinical significance in patients with multiple myeloma (MM).

Methods: The monocyte immunophenotypes expression of 67 MM and 30 anemic patients (control group) were detected by flow cytometry. The immunophenotypes that exhibited statistical differences from the control group were screened out. Further univariate and multivariate regression was used analyze the risk factors affecting the prognosis. The effect of monocyte immunophenotype on the prognosis of MM was analyzed. The correlation of CD38⁺ monocytes with clinical features was explored.

Results: The percentages of CD138⁺ monocytes (CD138⁺ M%), CD27⁺ monocytes (CD27⁺M%), and CD56⁺ monocytes (CD56⁺M%) in the MM group were significantly higher than that in the control group(P <0.05), but the percentages of CD38⁺ monocytes (CD38⁺ M%) and HLA-DR⁺ monocytes (HLA-DR⁺M%) were significantly lower than that in the control group (P < 0.01). The median progression-free survival (PFS) was shorter in the low CD38⁺ monocyte proportion (LCD38⁺ M%) group compared to the high CD38⁺ monocyte proportion (HCD38⁺M%) group. Additionally, the median overall survival (OS) was significantly shorter in the low CD138⁺ monocyte proportion (LCD138⁺M%), low CD27⁺ monocyte proportion (LCD27⁺M%), low CD38⁺ monocyte proportion (LCD38⁺M%), and low HLA-DR⁺ monocyte proportion (LHLA-DR⁺M%) groups. Cox regression analysis showed that the low CD38⁺M% was an independent risk factor for OS. The LCD38⁺M% group had significantly higher proportions of involved/uninvolved free light chain ratios ≥100 and 1q21⁺ compared to the HCD38⁺M% group (P < 0.05). Moreover, the proportion of CD38^- myeloma cells was significantly higher in the LCD38⁺M% group than that in the HCD38⁺M% group (P < 0.05).

Conclusion: The expression of CD38⁺ monocytes in bone marrow of MM patients is closely related to the prognosis and clinical characteristics. CD38⁺ monocytes maybe used to predict prognosis and guide treatment decisions.