Prognostic implication of leucocyte subpopulations in diffuse large B-cell lymphoma

BACKGROUND Recent studies have suggested that variables related to host adaptive immunity and the tumor microenvironment may predict the outcome in patients with non-Hodgkin's lymphoma. This study was undertaken to determine the prognostic value of peripheral blood leucocyte subpopulations in diffuse large-B-cell lymphoma patients. METHODS We prospectively analyzed the 16 leukocyte subpopulations using Cytodiff flow cytometric technique in a cohort of 45 diffuse large-B-cell lymphoma patients at a single institution between February and December 2014. The Cox proportional hazards model was used to evaluate prognostic factors for overall survival and progression free survival. RESULTS Diffuse large-B-cell lymphoma patients had decreased cytotoxic and non-cytotoxic NK&T cells as well as increased CD16+ monocytes, CD16- monocytes and mature neutrophils. The decreased CD16- monocyte/CD16+ monocyte ratio and increased mature neutrophil/cytotoxic NK&T cell ratio were related to poor progression-free and overall survival outcome in single and multivariate analysis. The co-constructed model using International Prognostic Index and mature neutrophil/cytotoxic NK&T cell ratio can also help discriminate the clinical outcome. CONCLUSIONS The decreased CD16-monocyte/CD16+monocyte ratio and increased mature neutrophil/cytotoxic NK&T cell ratio predict poor prognosis in diffuse large-B-cell lymphoma patients. This finding provides a strong rationale for the study of cellular immunotherapy in B-cell lymphoma.