EGFR and lung adenocarcinoma: The inclusion criteria were as follows: (1) stage IIIB-IV lung adenocarcinoma confirmed by histopathology; (2) patients of EGFR mutations with confirmed 19del or 21L858R; (3) no treatments received prior to EGFR TKIs therapy; (4) the EGFR-TKIs therapy was used as the first-line treatment; (5) with complete CT images within 2 weeks before EGFR-TKIs treatment.