Lung adenocarcinoma subgroup analysis showed that in patients receiving second cytotoxic chemotherapy, there were no significant differences in PFS between patients with low-CEA compared with those with high-CEA, but Positive-sHGF at pre-treatment or at response-evaluation predicted poor PFS (35.0 vs. 132.0; P < 0.01, 50.0 vs. 215.0; P < 0.01, respectively). The gene discussed is CEACAM5; the disease is lung adenocarcinoma.