Robot-assisted vs VATS for Thymoma

Inclusion Criteria: 1. ) The age of the subjects on the day of signing the informed consent was ≥ 18 years old and \< 75 years old, regardless of gender ; 2. ) Chest thin-layer CT and MR showed anterior mediastinal space-occupying lesions, combined with relevant hematological indicators, the patient was clinically diagnosed as a thymic epithelial tumor with or without myasthenia gravis ( MG ) symptoms. 3. ) need to accept thymectomy surgery ; 4. ) Clinical stage I to IIIA ( AJCC-UICC TNM staging system ) ; 5. ) The maximum diameter of the lesion \< 5cm ; 6. ) physical condition score 0 or 1 ( Eastern Cooperative Oncology Group ECOG scoring system ) ; 7. ) Have not received any anti-thymoma therapy before, including but not limited to systemic chemotherapy, radiotherapy, etc. ; 8. ) Preoperative major organ function meets the following criteria : Bone marrow function: hemoglobin ≥ 10.0 g / dL ( no blood transfusion within 28 days before hemoglobin examination ), absolute neutrophil count ≥ 1.5 × 109 / L, platelet count ≥ 100 × 109 / L ( no transfusion of apheresis platelets or IL-11 treatment within 14 days before platelet count examination ) ; coagulation function : INR and PT \< 1.5 × ULN, APTT ≤ 1.5 × ULN ; liver function: transaminase ( ALT and AST ) ≤ 2.5 × ULN; total bilirubin ≤ 1.5 × ULN ( Gilbert's syndrome or liver metastasis subjects total bilirubin ≤ 2.5 × ULN ) ; renal function: serum creatinine clearance rate ≥ 60 mL/min ( calculated according to the Cockcroft-Gault formula ) ; 9. ) voluntarily participated in and were able to undergo robot-assisted or thoracoscopic thymectomy, and complied with the study follow-up plan. Exclusion Criteria: 1. ) Patients with myasthenia gravis crisis ; 2. ) had undergone mediastinal surgery or cardiac surgery ; 3. ) body mass index ( BMI ) ≥ 30 ; 4. ) Patients with severe liver and kidney dysfunction ( ALT and/or AST more than three times the upper limit of normal, Cr more than the upper limit of normal ) ; 5. ) combined with severe chronic lung diseases such as COPD, asthma, or interstitial lung disease ; 6. ) suffering from uncontrolled heart, kidney, gastrointestinal, and infectious diseases and other complications ; 7. ) patients with other malignant tumors or hematological diseases ; 8. ) combined with chronic pain or preoperative use of opioid analgesics ; 9. ) patients with thoracic deformity or combined with pectus carinatum and pectus excavatum ; 10. ) have mental disorders, such as anxiety disorders ; 11. ) pregnant and/or lactating women ; 12. ) is currently participating in other interventional clinical studies.