Lack of cytoplasmic expression of a new marker programmed cell death ligand-1 in tumor cells is significant

Figure 1 Assessment of the severity of cytoplasmic programmed cell death protein 1 Ligand 1 expression in tumor cells. A: The percentage of tumor cells (TCs) without staining = 1, the percentage of TCs with weak staining = 0, the percentage of TCs with moderate staining = 2 and the percentage of TCs with strong staining = 1. The severity of cytoplasmic programmed cell death protein 1 ligand 1 (cPDCD1 LG1) expression in TCs = 8 (1 × 0 + 0 × 1 + 2 × 2 + 1 × 3); B: The percentage of TCs without staining = 0, the percentage of TCs with weak staining = 3, the percentage of TCs with moderate staining = 0 and the percentage of TCs with strong staining = 0. The severity of cPDCD1 LG1 expression in TCs = 3 (1 × 0 + 3 × 1 + 0 × 2 + 0 × 3); C: The percentage of TCs without staining = 1; the percentage of TCs with weak staining = 0; the percentage of TCs with moderate staining = 4; and the percentage of TCs with strong staining = 0. The severity of PDCD1 LG1 expression in TCs = 6 (1 × 0 + 0 × 1 + 3 × 2 + 0 × 3); D: The percentage of TCs without staining = 0; the percentage of TCs with weak staining = 0; the percentage of TCs with moderate staining = 1; and the percentage of TCs with strong staining = 3. The severity of PDCD1 LG1 expression in TCs = 11 (0 × 0 + 0 × 1 + 1 × 2 + 3 × 3). Staining with anti-PDCD1 LG1 antibodies. The scale bar is 200 μm.

Figure 2 Assessment of tumor-infiltrating programmed cell death protein 1 Ligand 1-positive immune cells. A: Cytoplasmic programmed cell death protein 1 ligand 1 (cPDCD1 LG1) + immune cell score ≥ 30%; B: PDCD1 LG1+ immune cell score < 10%. Staining with anti-PDCD1 LG1 antibodies. The scale bar is 200 μm.

Figure 3 Assessment of tumor-infiltrating lymphocytes. A: Tumor-infiltrating lymphocytes score < 5%; B: TIL score ≥ 10%. Staining with Mayer hematoxylin and eosin. The scale bar is 200 μm.

Figure 4 Cytoplasmic expression of programmed cell death protein 1 ligand 1 in nonneoplastic epithelium. A: Moderate cytoplasmic programmed cell death protein 1 ligand 1 (cPDCD1 LG1) expression in the normal ductal epithelium of the mammary gland; B: Moderate cytoplasmic PDCD1 LG1 expression in the epithelial cells lining cystic dilated ducts with apocrine metaplasia and intraductal secretion; C: Weak cytoplasmic expression in the atrophic epithelium lining cystic dilated ducts of the mammary gland; D: Pronounced cytoplasmic PDCD1 LG1 expression in the proliferating lobular epithelium. Staining with anti-PDCD1 LG1 antibodies. The scale bar is 200 μm.

Figure 5 Severity of cytoplasmic programmed cell death protein 1 ligand 1 expression in tumor cells according to estrogen receptor and progesterone receptor status. PD-L1: Programmed cell death-ligand 1; ER: Estrogen receptor; PR: Progesterone receptor; SE: Standard error.

Figure 6 Lack of cytoplasmic programmed cell death protein 1 ligand 1 expression in tumor cells. A: Lack of cytoplasmic programmed cell death protein 1 ligand 1 (cPDCD1 LG1) expression at the invasive edge of the tumor [in < 20% of tumor cells (TCs)]; B: Lack of cPDCD1 LG1 expression in the central part of the tumor (in ≥ 20% of the TCs); C: Lack of cPDCD1 LG1 expression in most of the tumor parenchyma; D: Severe basophilia and elongated shape of the TC nuclei in the absence of cPDCD1 LG1 expression. Staining with anti-PDCD1 LG1 antibodies, A-C: Scale bar is 200 μm, D: Scale bar is 50 μm.

Figure 7 Receiver operating characteristic curve. A: Receiver operating characteristic (ROC) curve for estrogen receptor status; B: ROC curve for progesterone receptor status; C: ROC curve for human epidermal growth factor receptor-2 status; D: ROC curve for the lack of cytoplasmic programmed cell death protein 1 ligand 1 expression in tumor cells; E: ROC curve for tumor-infiltrating programmed cell death protein 1 ligand 1-positive immune cell scores.