AR and breast cancer: Another study indicated that combining BCG or anti‐PD‐L1 therapy with ADT enhanced the efficacy of immunotherapy in vivo.[103] BC patients who received 5α‐reductase inhibitors had fewer cancer‐specific deaths than those who did not.[147] The AR‐mediated reduction in TCF7 and TCF1 expression in CD8+ T cells may lead to T cell exhaustion, contributing to an immunosuppressive TME and reduced immunotherapy efficacy in BC.[44b] Furthermore, neutrophils have been implicated in the AR‐induced progression of BC.