Tumor-Infiltrating Lymphocytes in Breast Cancer. Association with Clinical and Pathological Parameters

Abstract

In patients with primary resectable breast cancer, a positive correlation between the age and the count of CD16⁺ lymphocytes and a negative correlation of this parameter with the number of regulatory CD4⁺CD25⁺CD127^— cells and proliferative activity of Ki-67 tumor cells were revealed. Higher level of Ki-67 was associated with reduced number of effector lymphocytes (CD8⁺ and CD16⁺) and elevated content of regulatory CD8⁺CD11b^—CD28^— T cells. The absence of expression of estrogen receptors was associated with reduced cytotoxic potential of CD8⁺ T cell in comparison with ER⁺ breast cancer. The percentage of CD8⁺ lymphocytes (CD3⁺CD8⁺ and CD8⁺CD11b⁺CD28⁺) among lymphocytes infiltrating the tumor was higher in PR⁺ breast cancer than in PR^— tumors. With increasing the tumor load, the number of lymphocytes expressing CD16 marker and their cytotoxic potential decreased.