PGR and metastatic malignant neoplasm in the lymph nodes: Our results revealed that higher histological grade and lymph node metastasis were associated with higher PD-L1 expression in tumor and immune cells, and that PD-L1 expression in only tumor cells was associated with larger tumor size, higher histological grade, ER negativity, PR negativity, HER-2 negativity, and TNBC.