Inclusion Criteria:
1. Adult patients aged ≥ 18 years and ≤ 75 years with expected survival time \> 12 months;
2. Patients with systemic Myasthenia gravis;
3. AChR Antibody positive;
4. MGFA Type II- IV;
5. Clinical diagnosis of Neoplasm of thymus by enhanced chest CT (clinical stage: Masaoka-Koga Stage I-IVa);
6. Patients with American Society of Anesthesiologists (ASA) classification of 1-2;
7. Subjects have no dysfunction of major organs; blood routine, lung, liver, kidney function and cardiac function are basically normal; laboratory test indicators must meet the following requirements: Blood: White cells \> 4.0 x 109/L, absolute count of neutrophils (ANC) ≥ 2.0 x 109/L, Thrombocyte count \> 100 x 109/L, Hemoglobin \> 90 g/L; Lung function: FEV1 ≥ 1.2 L, FEV1% ≥ 50% and DLCO ≥ 50%. Note: FEV1: Forced vital capacity measured value (liter). FEV1%:% of Forced vital capacity observed/predicted. DLCO%: measured/predicted value% of diffusion capacity of the CO in one breath; Liver function: Serum bilirubin less than 1.5 times the maximum normal value; ALT and AST less than 1.5 times the maximum normal value; Renal function: blood creatinine (SCr) ≤ 120 µmol/L, creatinine clearance (CCr) ≥ 60 ml/min;
8. Understand the study and sign the informed consent form.
Exclusion Criteria:
1. Patients whose imaging investigation suggests that the tumor has already had hematogenous metastasis (clinical stage: Masaoka-Koga IVb);
2. Patients with ocular muscular myasthenia gravis (OMG);
3. Patients who have received median sternotomy ;
4. Documented history of congestive cardiac failure; poorly controlled drug therapy on Anginal pain; electrocardiogram (ECG) documented transmural myocardial infarction; poorly controlled hypertensive; clinically significant heart valve disorders; or high-risk uncontrolled arrhythmia;
5. Patients with a loss of more than 5 Kg within the past month; severe uncontrolled systemic intercurrent illness such as active Infection or poorly controlled Diabetes mellitus; patients with combined Hemorrhagic disorder and Haemorrhagic diathesis; patients with abnormal coagulation function, having haemorrhagic diathesis or receiving thrombolysis or anticoagulant therapy; and patients with grade II-IV myelosuppression.
6. Serum pregnancy test positive or lactating females, as well as males and females of childbearing potential who are unwilling to take adequate contraception measures during treatment;
7. History of organ transplant (including autologous bone marrow Transplant and peripheral Stem cell transplant);
8. Patients with peripheral nervous system disorders or significant history of Mental disorder and central nervous system disorders;
9. Concurrent participation in other clinical investigators.
10. Patients who cannot tolerate one-lung ventilation in the Surgery; patients with severe cardiac complications, cardiovascular compensatory dysfunction, cardiac pacemaker implantation;
11. Patients with acute Inflammation due to bacterial, viral or other pathogenic microorganism Infection; known Immunodeficiency virus (HIV), Hepatitis B virus (HBV) or Hepatitis C virus (HCV) active Infection or known HIV seropositivity;
12. Patients who previously underwent Thoracic operation for Tuberculous pleurisy, Mesothelioma, Pulmonary disorder, diaphragmatic disease, ipsilateral Atelectasis involving one lobe or more than one lobe;
13. Serum IgG level \< 6 g/L;
14. Received biologic agents such as rituximab or eculizumab within 6 months; IV Immunoglobulins or Plasma exchange within 1 month;
