Rationale for immunological approaches to breast cancer therapy

Despite great advances in early detection, as well as surgical resection of breast tumours, breast cancer remains the deadliest cancer for women worldwide. Moreover, its incidence is without pair, accounting for twice as many new cancer cases as the second most prevalent cancer, colorectal carcinoma. There is therefore a strong need for new therapeutic approaches to breast cancers. Immunotherapies are novel treatment modalities which aim to use immune mediators to attack cancerous cells. Recent clinical results show that these may not only mediate tumour regressions but also cures in some cases. In this review, we discuss the relevance of the immune system in the development of new carcinomas, as well as its importance in mediating cancer regression. We also dissect the known different approaches to harness the immune system to attack breast tumours. Namely, therapies using the passive transfer of either tumour-specific antibodies or cytotoxic cells have been researched and in some cases are already standard of care. Additionally, therapeutic vaccines and immune checkpoint blockade have recently demonstrated great therapeutic efficacy and have generated great excitement for the development of new treatments. Immunotherapies have the potential to generate tumour specific responses, as well as long-lasting remissions, which is why studying those approaches is crucial for the future of cancer medicine.