Abstract
Recent progress in immunotherapy has led to the routine use of immune checkpoint inhibitors (ICIs) in TNBC therapy and significant improvement in clinical outcomes. Incorporation of ICI into HR+/HER2- or HER2+ breast cancer has been hindered by its poor immunogenicity, and many novel combination strategies aim to convert immune cold tumors into immune hot tumors and increase the immunogenicity of HR+/HER2- breast cancer. A few recent clinical trials have shown its potential promise in high-risk HR+/HER2- early-stage breast cancer, but there is insufficient evidence to support routine use of immunotherapy in HR+ breast cancer, and longer-term follow-up is required to understand its impact on survival. This review presents an overview of immunotherapies currently under clinical development and updated key results from clinical trials, with a focus on HR+/HER2- breast cacner.