1. Department of Pulmonary and Critical Care Medicine; The Michael E. DeBakey VA Medical Center; Baylor College of Medicine; Houston; Texas; USA
2. Department of Pulmonary Medicine; The University of Texas MD Anderson Cancer Center; Houston; Texas; USA
3. Department of Thoracic Surgery; The Michael E. DeBakey VA Medical Center; Baylor College of Medicine; Houston; Texas; USA
4. Department of Pulmonary Medicine; The Cleveland Clinic Foundation; Cleveland; Ohio; USA