Prognostic significance of monocytes and monocytic myeloid-derived suppressor cells in diffuse large B-cell lymphoma treated with R-CHOP

Background/Aims: To evaluate the prognostic significance of monocytes and monocytic myeloid-derived suppressor cells (M-MDSCs) for patients with diffuse large B-cell lymphoma (DLBCL) under R-CHOP chemotherapy. Methods: Flow cytometry (FCM) was applied to measure M-MDSCs (CD14 ⁺ HLA-DR ^low/- M-MDSCs). Results: Analysis of 144 patients with DLBCL under R-CHOP treatment showed that the 5-year overall survival rate was 61.09% (95% CI: 43.72%-72.56%) and the average survival time of patients with monocytes (%) ≥ 8% was shorter than those with monocytes (%) < 8% (P = 0.0036). Further stratified analysis suggested that the average survival time of patients with monocytes (%) ≥ 8% was shorter than patients with monocytes (%) < 8% in the moderate outcome group (R-IPI = 1, 2) (P = 0.0168) and in the poorest outcome group (R-IPI > 2) (P = 0.0397), meanwhile, there was no significant difference in survival of patients with monocytes (%) ≥ 8% compared to patients with monocytes (%) < 8% in the best outcome group (R-IPI = 0) (P = 0.3106). Both of monocytes (%) and M-MDSCs were decreased in different R-IPI groups after 4-course of R-CHOP chemotherapy (P < 0.05). Conclusion: Our results indicated that monocytes (%) and M-MDSCs combined with R-IPI may be a simple and efficient immunological index to evaluate prognosis.