In a meta-analysis, Mao and colleagues showed an ORR of 3% (6/210) in patients with mutant KRAS NSCLC and of 26% (287/1125) in KRAS wt lung cancers, fulfilling the hypothesis that KRAS mutations represent negative predictive biomarkers for tumor response in NSCLC patients treated with EGFR-TKIs [131]. This evidence concerns the gene EGFR and non-small cell lung carcinoma.