We found that IGFBP7 expression was significantly elevated in EGFR-TKI-resistant cells, and that high plasma IGFBP7 levels or IGFBP7 IHC-positive tumors in patients with lung cancer were correlated with shorter PFS when EGFR-TKI was used as the first-line treatment. The gene discussed is EGFR; the disease is lung cancer.