Fig. 6: High density of intra-tumoral CD39⁺PD-1⁺CD8⁺ but not total CD8⁺ T cells correlates with disease-free survival in human breast cancer.

a Representative images of 5-color multiplex immunofluorescence on human breast cancer. Staining shows epithelial cells (PanCK + EpCAM, yellow), CD8⁺ T cells (CD8, magenta), PD-1 (green), CD39 (red) and nuclear staining (DAPI, blue). Scale bar is 50 µm. b Disease-free survival of 54 patients with high or low number of intra-tumoral CD39⁺PD-1⁺CD8⁺ T cells. c Disease-free survival of 54 patients with high or low number of intra-tumoral CD8⁺ T cells. The threshold for separating patients with high and low CD39⁺PD-1⁺CD8⁺ T cell densities was defined using ROC curve analysis. Survival was compared for patients with high and low density of cells to be compared as indicated for the individual graphs by Kaplan–Meier curves. Confidence intervals are indicated as shaded areas surrounding survival curves. Significance was calculated by log-rank test. Patient numbers at risk are displayed for each 15 years of follow-up.