1. Department of Medicine, The Jane and Leonard Korman Respiratory Institute, Division of Pulmonary and Critical Care Medicine, Thomas Jefferson University , Philadelphia, PA, USA
2. Department of Thoracic Medicine and Surgery, Lewis Katz School of Medicine, Temple University , Philadelphia, PA, USA
3. Department of Medical Oncology, Division of Population Science, Thomas Jefferson University , Philadelphia, PA, USA
4. Department of Family & Community Medicine, University of Pennsylvania , Philadelphia, PA, USA
5. Cancer Prevention and Control Program, Fox Chase Cancer Center , Philadelphia, PA, USA
6. Department of Radiology, University of Pennsylvania , Philadelphia, PA, USA
7. Department of Medicine, Division of Pulmonary, Allergy and Critical Care, University of Pennsylvania , Philadelphia, PA, USA