Advances in Immunotherapy for the Treatment of Metastatic Breast Cancer: A Comprehensive Review

• DOI: https://doi.org/10.22533/at.ed.1594922414106

• Palavras-chave: Immunotherapy; Metastatic Breast Cancer; PD-L1 Inhibition; TripleNegative Breast Cancer; Cancer Vaccines

• Keywords: Immunotherapy; Metastatic Breast Cancer; PD-L1 Inhibition; TripleNegative Breast Cancer; Cancer Vaccines

• Abstract: INTRODUCTION The introduction focuses on the evolving landscape of metastatic breast cancer treatment, highlighting the limitations of traditional therapies and the potential of immunotherapy. It introduces key concepts such as immune checkpoints, the tumor microenvironment, and the heterogeneity of breast cancer subtypes. The section emphasizes the importance of biomarker-driven therapies and sets the stage for discussing the current status and challenges of immunotherapy in breast cancer, particularly in triplenegative cases. OBJETIVE To explore the recent advancements in immunotherapy, including checkpoint inhibitors, CAR-T cell therapy, and cancer vaccines, and their impact on the treatment of metastatic breast cancer. METHODS This is a narrative review which included studies in the MEDLINE – PubMed (National Library of Medicine, National Institutes of Health), COCHRANE, EMBASE and Google Scholar databases, using as descriptors: “Immunotherapy” AND “Metastatic Breast Cancer” OR “Checkpoint Inhibitors” OR “Triple-Negative Breast Cancer” OR “Tumor Microenvironment” in the last years. RESULTS AND DISCUSSION The results and discussion sections delve into the efficacy of immunotherapy, particularly checkpoint inhibitors like pembrolizumab and atezolizumab, in metastatic triple-negative breast cancer. Clinical trials such as IMpassion130 and KEYNOTE-355 are reviewed, along with the challenges of immunotherapy resistance and the variability of responses based on biomarkers. Combination therapies are explored, including immunotherapy with chemotherapy, PARP inhibitors, and radiation. The section also addresses immune-related adverse events and the complexities of managing these treatments in a clinical setting. CONCLUSION The conclusion highlights immunotherapy as a breakthrough in metastatic breast cancer treatment, especially in triple-negative subtypes. It acknowledges the current limitations, such as biomarker variability and treatment resistance, but emphasizes the potential of combination strategies and personalized medicine to expand the benefits of immunotherapy. The section also calls for further research to optimize treatment protocols and reduce adverse effects, positioning immunotherapy as a cornerstone of future breast cancer treatment strategies