Clinical Significance of Circulating Neutrophils and Lymphocyte Subsets in Newly Diagnosed Patients with Diffuse Large B-cell Lymphoma

Lymphocytes play crucial roles in tumor surveillance in diffuse large B-cell lymphoma (DLBCL). Neutrophil-to-lymphocyte ratio (NLR), a biomarker for systematic inflammation, has been confirmed to be a prognostic factor for many malignant diseases. Herein, we conducted a systemic in-depth study of circulating neutrophils and lymphocyte subsets in DLBCL patients and their dynamics along with chemoimmunotherapy. A total of 61 patients with DLBCL were enrolled. Detection of lymphocyte subsets by flow cytometry was conducted at diagnosis and after 2/4/6/8 cycles' treatment of R-CHOP. Clinical significance, including incidence of infection, curative effect and disease-free survival (DFS), was analyzed based on the patients' clinical data and the quantity of lymphocyte subsets. The absolute numbers of neutrophils in stage III-IV DLBCL patients were obviously increased (p = 0.012), while the absolute numbers of lymphocytes were decreased (p = 0.025). Consequently, DLBCL patients had significantly higher NLR than healthy controls (p < 0.001). Further analysis of lymphocyte subsets showed a significantly reduced CD4 + T cells in DLBCL patients (p = 0.001). Patients with a lower lymphocyte counts (< 1.26*10E9/L) were more susceptible to infection (p < 0.001). NK cells were much higher in patients achieving complete remission than those of non-complete remission (p = 0.032). Higher neutrophils and NLR were closely associated with poorer DFS (p = 0.001 and p = 0.045, respectively). Circulating cells in DLBCL patients were dysregulated, featured with increased neutrophils and reduced lymphocytes. Higher NK cells before treatment predicted better therapeutic outcome. Higher neutrophils and NLR can be regarded as inferior prognostic predictors for DLBCL patients at diagnosis.