Abstract
Breast cancer, being the most common type of cancer globally, stands out as the primary malignant tumor affecting females. With the advent of breast cancer immunotherapy, inhibitors targeting immune checkpoints such as anti-PD-1 (Programmed cell death protein 1) / PD-L1 (Programmed cell death-Ligand 1) and CTLA-4 (Cytotoxic T Lymphocyte-Associated Antigen-4) have demonstrated promising outcomes for breast cancer patients across all molecular subtypes, particularly those with advanced breast cancer and triple-negative breast cancer (TNBC). Our current focus lies in accurately predicting the prognosis of breast cancer patients and the effectiveness of immunotherapy. This article provides a review of emerging biomarkers for breast cancer, encompassing immune-related markers, metabolic indicators, and potential prognosis-related markers. The primary emphasis of the article is to review immune-related tumor biomarkers in breast cancer. Our goal is to summarize relevant studies capable of forecasting breast cancer prognosis and immunotherapy effectiveness. Lastly, we delve into the future directions of breast cancer immunotherapy development.