Correlation between circulating blood and microenvironment T lymphocytes in diffuse large B-cell lymphomas

Aims: Diffuse large B-cell lymphoma (DLBCL) is characterised by marked clinical and biological heterogeneity, attributable to the tumour cells and their microenvironment. Methods: In this study, we investigated circulating subsets of blood lymphocytes and monocytes and their relationship with T cells in the tumour microenvironment (TME) in chemoresistant and chemosensitive patients with DLBCL. Results: The study showed that (1) absolute lymphocyte count (ALC) and CD3+ and CD4+ cells were reduced in chemoresistant patients compared with chemosensitive patients; (2) lymphocyte:monocyte ratio (LMR) showed a positive correlation with peripheral blood CD3+ and CD4+ cells; (3) ALC, LMR, peripheral blood CD3+ and CD4+ cells showed a positive correlation with T cells in the TME. Conclusions: Overall, these data suggest that DLBCL with high TME T cells display a pre-existing antitumour immune response. In the rituximab-containing regimen, TME T cells are stimulated further to participate in the immune response against lymphoma cells. In contrast, DLBCL lymphomas with low T-cell infiltration reflect the absence of a pre-existing antitumour immunity and have a lower likelihood of obtaining an optimal response to therapy.