title: Minimally invasive resection of thymomas with the da Vinci® Surgical System.
abstract: OBJECTIVE
  The resection of thymic tumours requires completeness and may be technically challenging due to the anatomical proximity of the delicate mediastinal structures. An open approach by sternotomy is still recommended in all cases with locally extended disease. Video-assisted thoracoscopic surgery is feasible, but limited by the two-dimensional vision and the impaired mobility of the instruments. We evaluated the da Vinci® Surgical System for the resection of various mediastinal pathologies, particularly thymomas.
  
  
  METHODS
  Among 105 patients operated on by robotic assisted thoracoscopic surgery (RATS) for mediastinal tumours between 27 August 2004 and 12 July 2011, 20 patients with thymomas were studied prospectively. Of these, 10 males with a median age of 53 years, with a well-circumscribed thymic lesion on computed tomography (CT) and a diameter of <6 cm were resected by RATS alone, and selected ones (n = 3), with a diameter of >6 cm, underwent a hybrid procedure with a contralateral thoracotomy on the side of the main tumour extension. A regular follow-up with chest CT scans was performed every 6 months.
  
  
  RESULTS
  Thymoma resection was complete in all patients. Partial pericardial resection was needed in five and pulmonary resection in two patients. Eighty-five percent of patients had an R0 resection. Histological classifications included thymoma WHO type A (n = 3), AB (n = 8), B1-2 (n = 5) and B3 (n = 4). All B3 thymomas received adjuvant radiotherapy. No intraoperative complications occurred. The median hospitalization time was 5 days (range 2-14 days). There were no local, but two pleural, recurrences. After a median observation time of 26 months, 19 patients (95%) are alive.
  
  
  CONCLUSIONS
  Well-circumscribed thymomas can be safely and completely resected with the da Vinci® Surgical System with excellent short- and mid-term outcomes. Selected tumours with large diameters may be resectable using a hybrid procedure combining RATS with a thoracotomy.
authors.affiliation: Department of Surgery, Division of Thoracic Surgery, University Hospital Zurich, Zurich, Switzerland. didier.schneiter@usz.ch
authors.forename: Didier
authors.initials: D
authors.lastname: Schneiter
authors.forename: Sandra
authors.initials: S
authors.lastname: Tomaszek
authors.forename: Peter
authors.initials: P
authors.lastname: Kestenholz
authors.forename: Sven
authors.initials: S
authors.lastname: Hillinger
authors.forename: Isabelle
authors.initials: I
authors.lastname: Opitz
authors.forename: Ilhan
authors.initials: I
authors.lastname: Inci
authors.forename: Walter
authors.initials: W
authors.lastname: Weder
mesh_terms: D015331:Cohort Studies; D005260:Female; D006801:Humans; D007902:Length of Stay; D008297:Male; D008875:Middle Aged; D011300:Preoperative Care / Q000379:methods; D012129:Respiratory Function Tests; D012371:Robotics; D020775:Thoracic Surgery, Video-Assisted / Q000379:methods*; D013945:Thymoma / Q000473:pathology / Q000601:surgery*; D013953:Thymus Neoplasms / Q000473:pathology / Q000601:surgery*; D016896:Treatment Outcome