Figure 1.

Immunohistochemical staining for primary antibodies against CD4, CD8, Foxp3, programmed cell death ligand 1 (PD‐L1), PD‐L2, and HLA class I to characterize tumor‐infiltrating lymphocytes. Representative photographs are shown from the same patient who had human epidermal growth factor receptor‐2‐positive primary breast tumor (left column) and lung metastasis (right column). Original magnification, ×400.