Immunology and immunotherapy of breast cancer

Abstract

It has become increasingly evident that immune cells can control the clinical progression of breast cancer. In addition, certain chemotherapeutic drugs and targeted therapies used for treatment of breast cancer have been shown to modulate immunity as part of their mechanism of action. Thus, analysis of tumor-infiltrating immune cells and their pro- and antitumor effects offers the hope of prognostic information and the identification of patients most likely to respond to immunotherapies. In this chapter, we discuss the role of the immune system in breast cancer, with a focus on the prognostic value of specific immune cell subsets and how these could be harnessed or inhibited for the treatment of certain types of breast cancer. Particularly, we discuss the large amount of preclinical and correlative data that associates immune infiltrates, cells, and immune gene signatures with prognosis and therapeutic efficacy in estrogen receptor-negative and HER2+ breast cancer.