Breast Cancer Immunotherapy

Although unlikely to replace current standard of care therapies, immunotherapy is emerging as a critical component of breast cancer treatment. Despite initial setbacks, clinical benefit is now evident through immunomodulation and cancer vaccines. Over the past decade, passive immunotherapeutic strategies such as anti-HER2 monoclonal antibody (mAb) therapy have significantly improved the prognosis in HER2 overexpressing breast cancers. Novel active immunotherapeutic strategies include checkpoint blockade modifiers, also a mAb therapy. Although non-specific, checkpoint blockade modifiers show great promise in clinical trials. A form of active and specific immunotherapy, cancer vaccines may be used alone or in conjunction with these aforementioned mAb therapies. While there is significant initial promise, the complexities of the host immune system-tumor interaction and the vast array of potential immune targets require the field of cancer immunotherapy to be further developed. Here, we briefly discuss the field of breast immunotherapy to date and its implications for the future of breast cancer care.