Efficacy and Safety of Apatinib as Third-line Therapy for Primary Pulmonary Lymphoepithelioid Carcinoma

Inclusion Criteria:

* patients aged from 18 to 75;
* ECOG PS: 0 \~ 2 points;
* lung lymphoepithelioid carcinoma;
* Inoperable stage IV or stage III-B patients who had undergone second-line chemotherapy and had a measurable lesion (according to the RECIST 1.1 standard, the long diameter of the tumor lesion was 10mm in CT scan, the short diameter of the lymph node lesion was 15mm in CT scan, and the lesion was measured without local treatment such as radiotherapy and freezing).
* Life expectancy ≥3 months;
* the main organs are functioning normally:

  1. HB≥80 g/L(no blood transfusion within 14 days); ANC≥1.5×109 /L； PLT≥100×109 /L； WBC≥3×109 /L；
  2. TBIL≤1.5×ULN (upper limit of normal value); ALT and AST ≤2.5×ULN；
  3. creatinine ≤ 1.25 ULN; The clearance rate of creatinine ≥ 60mL/min.
  4. 24-hour urinary protein quantification \< 1.0g;
* women of reproductive age (15 to 49 years old) must undergo a urinary pregnancy test within 7 days before starting treatment and the results must be negative. Women are willing to use appropriate methods of contraception;
* Subjects signed the informed consent voluntarily.

Exclusion Criteria:

* Histologically proved to be other types of lung cancer, patients with nasopharyngeal lymphatic epithelial carcinoma with lung metastasis should be excluded.
* Imperfection of upper gastrointestinal physiology, or absorption disorder syndrome, or inability to tolerate oral drugs, or active peptic ulcer;
* Participated in other clinical trials within 4 weeks before the start of the study;
* patients with hypertension who cannot control well through single antihypertensive medication (systolic blood pressure \> 140mmhg, diastolic blood pressure \> 90mmhg), myocardial ischemia or myocardial infarction, arrhythmia (including QT interval \> 440 ms) or cardiac insufficiency;
* Allergic to any ingredient in the drug;
* Patients with abnormal coagulation function, receiving thrombolysis or anticoagulation therapy, bleeding tendency or have clear gastrointestinal bleeding concerns;
* Hyperactive/venous thrombosis events, such as cerebrovascular accident (including transient ischemic attack), deep venous thrombosis and pulmonary embolism occurred in 6 months before the start of the study;
* Wound or fracture has not been healed for a long time;
* urinary protein was greater than ++ and 24-hour urinary protein quantification \>1.0 g.
* Severe or uncontrolled infections;
* Substance abuse or mental disorder;
* Objective evidence of a history of pulmonary fibrosis, interstitial pneumonia, pneumoconiosis, radioactive pneumonia, drug-related pneumonia, and severe impairment of pulmonary function;
* Immunodeficiency, including being HIV-positive, or having other acquired, congenital immunodeficiency diseases, or having a history of organ transplantation;
* Other malignant tumors within 5 years, except cured basal cell carcinoma of the skin and orthotopic carcinoma of the cervix;
* Who have received VEGFR inhibitors, such as sorafenib and sunitinib, etc.;
* pregnant or lactating women;
* the researchers considered it unsuitable for inclusion.