Anlotinib has been approved as a third-line treatment for advanced non-small-cell lung cancer. A phase II clinical studies of small cell lung cancer (ALTER-1210) also showed that, compared with placebo, Anlotinib could improve the patients survival and had less toxic side effects after 2-3 line therapy. The purpose of this multicenter, randomized, prospective study is to investigate the efficacy and safety of Anlotinib as the maintenance therapy for Extensive-stage small cell lung cancer after combined with etoposide and cisplatin chemotherapy.

Inclusion Criteria:

• Histologic or cytologic diagnosis of small cell lung caner

• Advanced small cell lung cancer who had no prior cisplatin-based chemotherapy or radiotherapy,at least one measurable lesion (by RECIST1.1)

• Males or females between 18 Years to 75 Years.

• Performance status of 0～2 on the ECOG criteria.

• Main organs function is normal

• Expected survival is above three months.

• with asymptomatic brain metastases.

• At least one measurable lung tumor lesion (according to RECIST criteria, the application of conventional technology, diameter length of the lesion >= 20mm or spiral CT >=10mm).

• Adequate hematologic (Leukocyte count >= 4.0×109/L, neutrophil count>=2.0×109/L, hemoglobin>=95g/L, platelets>=100×109/L), hepatic function (aspartate transaminase (AST) & alanine transaminase(ALT)

  =<upper normal limit(UNL) x1.5, bilirubin level =< UNL x 1.5).

• Patient can take oral medicine.

• Patients have the ability to understand and voluntarily sign the informed consent, and allow adequate follow-up.

Exclusion Criteria:

• History of cardiovascular disease: congestive heart failure (CHF) > New York Heart Association (NYHA) II, active coronary artery disease(patients with myocardial infarction six months ago can be recruited), arrhythmias need to be treated (allow taking beta blockers or digoxin).
• Serious clinical infection (> NCI-CTCAE version 4.0 ,infection standard II).
• Patients with epilepsy who need to take medicine (such as steroids or anti epilepsy agents).
• The patients had accepted allogeneic organ transplantation.
• Bleeding tendency or coagulation disorders.
• patients who need renal dialysis.
• suffered from other tumor within 5 years( Except: cervical carcinoma in situ, cured basal cell carcinoma, cured bladder epithelial tumor).
• uncontrolled hypertension (systolic pressure>150 mmHg , or diastolic pressure> 90 mmHg).
• thrombosis or embolism(cerebrovascular accidents including transient ischemic attack within the last 6 months).
• pulmonary hemorrhage >CTCAE grade 2 within 4 weeks before first use of drugs.
• Other organ hemorrhage >CTCAE grade 3 within 4 weeks before first use of drugs.
• severe uncured wounds, ulcers or fracture.
• uncured dehydration.
• Drugs abuse and medical, psychological or social conditions may interfere with the patient's participation in research or the results of the evaluation effect.
• Patients are allergic to drugs used in research.
• Factors influencing the safety and compliance of patients.
• Inability to comply with protocol or study procedures.
• Pregnant or breast-feeding.
• The researcher believe that the Patient is not suitable to participate in the study.