Lung adenocarcinomas with EGFR Mut in exon 19 had a lower R-score* than ones with EGFR Mut in exon 21 in training dataset (−0.39 ± 1.35 vs. 0.27 ± 1.12, P = 0.000) and in validation dataset (−0.70 ± 1.25 vs. 0.23 ± 1.12, P = 0.000) (Table 3). This evidence concerns the gene EGFR and lung adenocarcinoma.