A previous study reported the IPS as a predictor of the response to ICI therapy, which was constructed based on 4 gene categories: effector cells, suppressive cells, MHC-related molecules and immunomodulators.[16] Since the cohort with ICI therapy in breast cancer was not available, we used IPS as a surrogate of the breast cancer patients’ response to ICI. This evidence concerns the gene HLA-C and breast cancer.