PDCD1LG2 and breast cancer: In this study, the expression of PD-L1, CTLA4, PDCD1, PDCD1LG2 and HAVCR2 in high focus death score was found to increase, and combined with the results of the literature, it can be shown that immunotherapy in patients with PD-1/PD-L1-positive breast cancer has significant therapeutic advantages and clinical efficacy.