Tumour-infiltrating CD4 and CD8 T lymphocytes in breast cancer

Lymphocytes are cells circulating between the blood and tissues. It has been stated that a correlation exists between immune infiltrate and breast cancer. These tumours are infiltrated by T cells, B cells, natural killer cells and macrophages. The infiltrating T cells are of helper (CD4(+)) and cytotoxic (CD8(+)) phenotypes. Specific immunity mediated by cytolytic T lymphocytes is suspected of playing an anticancer role. It is widely known that regional lymph nodes are an important immunological defence or "barrier" against tumour expansion. Some authors have reported that in cancer patients natural killer (NK) cells and CD8(+) T cells are diminished in regional lymph nodes, particularly those involved by the tumour. In the presented study the authors review current knowledge on this problem and the possibility of using successful immunotherapy with monoclonal antibodies for breast cancer.