The KEYNOTE-001 study showed that in patients with PD-L1 overexpression (i.e., tumor proportional score [TPS] > 50%), pembrolizumab was less effective in EGFR-mutant tumors than in EGFR wild-type tumors (median overall survival = 6.5 vs. 15.7 months, respectively) [63, 64]. Here, EGFR is linked to neoplasm.