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

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.