Analysis of the treg cell population in the peripheral blood of ovarian cancer patients in relation to the long-term outcomes.

Objectives: There is growing evidence that Treg cell infiltration into the cancer nest is associated with poor prognosis. How- ever, the Treg cell population in the peripheral blood may change when a different type of anticancer therapy is applied. Since Treg cells may support tumor growth by enhancing the suppressive profile of the cancer microenvironment, the assessment of Treg cells can bring to light important information regarding prognosis. Thus we decided to analyze the Treg cell population in the peripheral blood in relation to long-term outcomes in the group of patients with ovarian cancer.

Material And Methods: The 80 patients included in the study were treated surgically followed by chemiotherapy for ovar- ian cancer between October 2010 through May 2011.The peripheral blood samples from the patients were collected directly prior to chemotherapy. Information on any patients who died was retrieved from the database of the Cuiavia-Pomerania Regional Office of the National Health System of Poland. CD4+CD25+FOXP3+ lymphocytes T were assed by flow cytometry. We have analyzed the long term outcomes of treatment regarding to the level of Treg cells in peripheral blood.

Results: We found that patients with serous adenocarcinomas had significantly higher Treg levels compared to those patients with non-serous types. Patients who had a higher percentage of Treg cells within the CD4+ cell population prior to the beginning of the treatment had worse long-term outcomes from the applied therapy.

Conclusions: The assessment of Treg levels prior to the start of chemotherapy is clinically useful and may predict overall survival in ovarian cancer patients.