Clinical efficacy of Apatinib combined with Epidermal growth factor receptor - tyrosine kinase inhibitor (EGFR-TKI) in nonsmall cell lung cancer after EGFR-TKI resistance

To evaluate the efficacy and safety of Apatinib combined with epidermal growth factor receptor - tyrosine kinase inhibitor (EGFR-TKI) in the treatment of patients with non-small cell lung cancer (NSCLC) and acquired EGFR-TKI resistance.