T-helper/T-regulator lymphocyte ratio as a new immunobiological index to quantify the anticancer immune status in cancer patients.

Background:Theevaluationoftheimmunestatus of cancer patients is not routinely included in clinical oncological practice mainly because of the great number of candidate immune parameters that could potentially be the bestindexofthestatusofanticancerimmunity.Untilrecently, the T-helper/T-suppressor lymphocyte ratio (CD4/CD8) was considered to be an index of immunosuppression in cancer patients. Successive studies documented the existence of several subtypes of CD4 + lymphocytes, as well as showing that CD8 + cells were not in fact suppressive, but cytotoxic lymphocytes. More recently, the existence of a subtype of T-helper lymphocytes has been demonstrated provided by an evidentsuppressiveactivityonanticancerimmunity.Theseare the so-calledT-regulator (T-reg) lymphocytes, which may be detected as CD4 + CD25 + cells. Materials and Methods: A study was carried out to evaluate CD4 + /CD4 + CD25 + ratio, corresponding to the T-helper/T-reg cell ratio (TH/TR), in a group of 50 cancer patients in relation to their disease extension and in 20 healthy controls. Results: The mean TH/TR ratio observed in patients with metasy tases was significantlylowerwithrespecttothatfoundinbothpatients without metastases and controls. On the contrary, the absolute mean number of T-reg cells was higher in patients with metastases than in those without, but the difference was not statistically significant. Conclusion: The evaluation of T-reg cells in terms of their proportion with respect to T-helpercelltotalnumberseemstobemoreappropriatethan