As for the multivariable analysis adjusting for age and stage, PD-1 still predicted better survival for BC patients (HR = 0.71, 95% CI 0.50–0.99, P = 0.045) but PD-L1 showed no significant relation (HR = 0.99, 95% CI 0.71–1.37, P = 0.934). Here, PDCD1 is linked to breast cancer.