We assessed the association between baseline tumor characteristics (TMB, PD-L1, CD4, and CD8) and clinical features and outcome in 38 patients with advanced NSCLC treated with pembrolizumab....Baseline tumor CD8 (but not CD4) infiltration was significantly higher in patients with longer PFS when assessed as a continuous variable (P = 0.026; Table 2; Fig. 2) and with longer OS when assessed as a categorical variable (P = 0.048)...