KDR and small cell lung carcinoma: As a small-molecule inhibitor of VEGFR-2 tyrosine kinase, Apatinib blocks the transmission of the signaling pathway of VEGF/VEGFR-2, and has shown efficacy against a variety of cancers, including SCLC.189 A retrospective study showed that apatinib displayed efficiency in patients with ES-SCLC after failure of more than two prior chemotherapy regimens.190 A prospective, single-arm, phase II study was conducted to evaluate the safety and efficacy of apatinib in combination with etoposide taken orally as a third or subsequent line of treatment for ES-SCLC.