Surgery for Masaoka-Koga I-II Thymoma

Inclusion Criteria:

1. Thymoma was diagnosed by chest enhanced CT (clinical stage: Masaoka Koga I-II);
2. The patients whose tumor diameter was \<6 cm;
3. The patients with age ≥ 18 and ≤ 75 years old, the estimated survival time should be over 12 months;
4. ASA grade：1-2;
5. The patients should have no functional disorders in main organs.;
6. The patients should be able to understand our research and sign the informed consent.

Exclusion Criteria:

1. Imaging examination showed that the tumor had invasion of surrounding organs, pleural or pericardial dissemination, lymphatic or hematogenous metastasis;
2. Patients with myasthenia gravis;
3. Patients had undergone a sternotomy;
4. The patients have proved history of congestive heart failure, angina without good control with medicine; ECG-proved penetrating myocardial infarction; hypertension with bad control; valvulopathy with clinical significance; arrhythmia with high risk and out of control;
5. The patients have severe systematic intercurrent disease, such as active infection or poorly controlled diabetes; coagulation disorders; hemorrhagic tendency or under treatment of thrombolysis or anticoagulant therapy;
6. Female who is positive for serum pregnancy test or during lactation period;
7. The patients have history of organ transplantation (including autologous bone marrow transplantation and peripheral stem cell transplantation;
8. The patients have history of peripheral nerve system disorders, obvious mental disorders or central nerve system disorders;
9. The patients attend other clinical trials.