1 Department of Oncology, Xinqiao Hospital, Third Military Medical University, Chongqing, China.
2 Department of Respiratory Disease, Xinqiao Hospital, Third Military Medical University, Chongqing, China.
3 Department of Pneumology and Critical Care Medicine, Thoraxklinik, and Translational Lung Research Center Heidelberg, University of Heidelberg, Heidelberg 69126, Germany. Electronic address: felix.herth@med.uni-heidelberg.de.