1. Department of Surgery, Hôpitaux Universitaires de Genève , Geneva, Switzerland
2. Thoracic Unit, Department of Surgery, Hôpital Cantonal de Fribourg , Fribourg, Switzerland
3. Division of General Thoracic Surgery, Inselspital Bern, Bern University Hospital , Bern, Switzerland
4. Department of Internal Medicine and Pneumology, Hôpital Cantonal de Fribourg , Fribourg, Switzerland