Clinical Study of Combined Radical Operation With Postoperative Adjuvant Chemotherapy and Prophylactic Cranial Irradiation in pT1-2N0M0 Stage of Small Cell Lung Cancer

Inclusion Criteria:

* Signed informed consent;
* Ability to follow research programs and follow-up procedures;
* \* Patient age ≥ 18 years old;
* Histology or cytology confirmed as SCLC, chest enhancement ct, liver and adrenal ct, skull MRI, pet-ct/whole body bone scintigraphy, ebus puncture biopsy, etc. clearly as the t1-2n0 period of the initial treatment of patients (according to the UICC 2009 version of the phased standard);
* Radical resection of the leaf, the postoperative confirmed margin negative, pathological stage of t1-2n0 stage of small cell lung cancer;
* 4-week EP or EC regimen for adjuvant chemotherapy after surgery;
* Physical status ECOG assessment is divided into 0\~1;
* Life expectancy at least 12 weeks;
* The following laboratory tests conducted within 21 days of the end of the 4th cycle of chemotherapy confirmed that the patient's bone marrow, liver and kidney function met the requirements for participation in the study:
* Hemoglobin ≥9.0 g/dl (can be maintained or exceeded by blood transfusion);-Neutrophil absolute Count (ANC) ≥1.5x109;
* Platelet count ≥100x109/mm3;
* Total bilirubin ≤ 1.5 times times normal value upper limit;
* Alt and Straw transaminase ≤ 2.5 times times the normal value of the upper limit;
* creatinine ≤ 1.5 times times the upper limit of normal value and creatinine clearance rate ≥60ml/min; -prothrombin Time International standardized ratio (INR) ≤1.5, and part of the clotting activity Time (APTT) ≤ 1.5 times times the normal value limit.
* Patients who received a full or parenteral anticoagulation treatment had a minimum dose of anticoagulant for at least 2 weeks before entering clinical studies, and the results of the coagulation test were available for clinical trials within the limits of local treatment.
* Women of childbearing age must be tested in pregnancy for 7 days prior to initiation of treatment and negative results.
* Men and women of the appropriate age are required to use a reliable method of contraception until 30 days after withdrawal from the study before entering the trial. Reliable contraceptive methods will be judged by the principal researcher or designated person.

Exclusion Criteria:

* Patients who have conducted any systemic anticancer therapy for SCLC, including cytotoxic drug therapy, targeted drug therapy and experimental therapy.
* Localized radiotherapy for SCLC;
* Patients with cancer other than SCLC in the five years prior to the start of the study.
* Except for cervical in situ carcinoma, cured basal cell carcinoma, bladder epithelial tumor \[including TA and tis\];
* Any unstable systemic disease (including active infections, uncontrolled high blood pressure, unstable angina pectoris, onset of angina in the last 3 months, congestive heart failure (≥ "NYHA" Grade II), cerebral infarction (6 months before the group), severe arrhythmia requiring medical treatment, Diagnosis with liver, kidney or metabolic disease;
* Has or is currently suffering from interstitial lung disease;
* Lack of full control of ocular inflammation or eye infections, or any condition that may cause such ocular diseases;
* Known human immunodeficiency virus (HIV) infection;
* Allergy to any kind of research drug;
* Patients undergoing major surgery or severe trauma within 2 months prior to the first medication;
* any negative absorption;
* Pregnant or lactating women;
* Other researchers do not think fit into the group.