Standard treatment or active comparator group contains a platinum drug and a topoisomerase inhibitor. Platinum drug=cisplatin 75 mg/m2 iv on day 1; topoisomerase inhibitor=etoposide 120 mg/m2 iv day 1-3, 3 weeks a cycle, total numbers of cycles 6.Used drugs=cisplatinum and etoposide.

Apatinib treatment or experimental group contains standard chemotherapy and apatinib, a VEGF tyrosine kinase inhibitor. It contains a platinum drug, a topoisomerase inhibitor and a VEGF-TKI. Platinum drug=cisplatin 75 mg/m2 iv on day 1; topoisomerase inhibitor=etoposide 120 mg/m2 iv day 1-3, 3 weeks a cycle, total numbers of cycles 6.Used drugs=cisplatinum and etoposide. Numbers of cycles 6. In addition to this, subjects will receive VEGF-TKI=apatinib, 500 mg, oral daily after chemotherapy, until disease progression or death or un-tolerated toxicites. Used drugs=cisplatinum and etoposide and apatinib.

The recommended regimen is cisplatin plus etoposide. cisplatin 75 mg/m2 iv on day 1, etoposide 120 mg/m2 iv on day 1-3, 3 weeks a cycle, total for 6 cycles is allowed.

from the date of randomization to disease progression