Appraisal of immune response in lymphoproliferative syndromes: a systematic review

In lymphoproliferative syndromes, tumoural-immune cell interactions depend on a number of factors related to tumoural and immune cells. Recent gene expression data tend to confirm the decisive role of the reactive microenvironment in the development and clinical behaviour of lymphoproliferative syndromes, and encourage particular interest in the role of T cells and accessory cells. This systematic review brings together the accumulated knowledge about "immune signatures" in Hodgkin and non-Hodgkin lymphomas. Extracted results revealed that the presence of T lymphocytes, regulatory T cells and non-activated CTL in the reactive microenvironment appear commonly to be related with a favourable outcome in the majority of lymphoproliferative syndromes, whereas the presence of TAM, NK cells and activated CTLs appear more usually related with a poor prognosis. The direct involvement of these "immune signatures" in the histopathological morphology, classification, clinicobiological characteristics and outcome of affected patients stimulates the search for new and more appropriate immunotherapeutic strategies.