Global breast cancer rates surge, challenging treatments. Despite past therapies, relapse and metastasis persist. Promisingly, cancer vaccines offer new hope when combined with anti-HER2 antibodies or immune checkpoint blockade.

Globally, breast cancer ranks as the most frequently diagnosed cancer, accounting for approximately 2.3 million new cases in 2020. It is characterized by its heterogeneity, with clinical classification primarily based on estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2) status. Despite significant progress in endocrine and anti-HER2 therapies, breast cancer relapse and metastasis challenges require innovative treatments. Recent studies have highlighted the relevance of tumor-infiltrating lymphocytes (TILs) in treatment response and prognosis, particularly in breast cancer patients. This, coupled with the success of immune checkpoint blockade (ICB) in various solid tumors, has spurred interest in breast cancer immunotherapy.

Immunotherapeutic approaches encompass passive and active strategies. Passive immunotherapy includes anti-HER2 targeted therapies using monoclonal antibodies like trastuzumab and pertuzumab. In contrast, active immunotherapy revolves around cancer vaccines, designed to activate a patient’s immune cells, inducing an anti-tumor immune response for therapeutic benefits. This review delves into the principles, mechanisms, vaccine types, administration methods, and current clinical trial outcomes related to breast cancer vaccines. It also addresses present challenges and explores potential future directions in this evolving field.

Fundamentals of Breast Cancer Vaccination:

  • Immunoediting in Tumor Progression.
  • Immune Cells’ Recognition of Tumor Antigens.
  • Tumor Cells’ Strategies to Dampen Anti-Tumor Immunity.

Active breast cancer vaccines offer potential advantages like lower toxicity and durable, tumor-specific immunity. However, clinical trials have yielded limited benefits, possibly due to fading immune responses, immune tolerance, and tumor’s immunosuppressive environment. Optimizing dosing, delivery, and formulations, along with targeting specific tumor characteristics, are essential. Despite challenges, the concept of mobilizing the immune system against cancer remains promising, with ongoing efforts to enhance vaccine efficacy as cancer immunology understanding advances.


  1. Source: Zhu SY, Yu KD. Breast cancer vaccines: disappointing or promising?. Frontiers in Immunology. 2022 Jan 28;13:828386.
  2. Frontiers Media S.A.