In atezolizumab monotherapy, TMB, PD-L1 on both cancer cells and APCs, Teff density as well as Teff/Treg ratio in tumor were significantly higher in responders, whereas T cell PD-1 expression and atezolizumab cross-arm binding efficiency (χ) were not significantly different between responders and NRs (figure 4A). Here, PDCD1 is linked to cancer.