EGFR and non-small cell lung carcinoma: In the present study, serum IGFBP-3 levels measured before EGFR-TKI treatment and after the development of EGFR-TKI resistance in 20 NSCLC patients showed no significant changes (1815.3±94.6 ng/mL before treatment vs. 1778.9±87.8 ng/mL after EGFR-TKI resistance).