1. Department of Thoracic Surgery, West German Cancer Center, University Medical Center Essen-Ruhrlandklinik, University Duisburg-Essen, 45239 Essen, Germany
2. Department of Thoracic Surgery, Regiomed-Klinikum Coburg GmbH, 96450 Coburg, Germany
3. Clinic for Oral Surgery, 40879 Ratingen, Germany
4. Institute of Zoology, Faculty of Mathematics and Natural Sciences, University of Cologne, 50674 Cologne, Germany
5. Department of Thoracic Surgery, Helios Clinic Bonn/Rhein-Sieg, 53123 Bonn, Germany
6. Division of Thoracic Surgery, Department of General, Thoracic and Vascular Surgery, Bonn University Hospital, 53127 Bonn, Germany
7. Department of Cardiothoracic Surgery, University Hospital of Cologne, University of Cologne, 50937 Cologne, Germany
8. Clinic for Pneumology and Allergology, Bethanien Hospital GmbH, 42699 Solingen, Germany
9. Lung Cancer Group Cologne, Department I of Internal Medicine, University Hospital Cologne, University of Cologne, 50937 Cologne, Germany
10. Interdisciplinary Thoracic Center, Division of Thoracic Surgery, University Hospital of Mainz, University of Mainz, 55131 Mainz, Germany
11. Department of Medical Oncology, West German Cancer Center, University Medical Center Essen, University Duisburg-Essen, 45147 Essen, Germany
12. National Center for Tumor Diseases (NCT) West, Campus Essen, 45147 Essen, Germany