1. Department of Radiation Oncology, Fourth Hospital of Hebei Medical University, Shijiazhuang, Hebei 050011, P.R. China
2. Department of Radiation Oncology, Xinle Hospital of Traditional Chinese Medicine, Shijiazhuang, Hebei 050700, P.R. China
3. Department of Thoracic Surgery, Fourth Hospital of Hebei Medical University, Shijiazhuang, Hebei 050011, P.R. China
4. Department of Thoracic Surgery, Shangqiu First People's Hospital, Shangqiu, Henan 476100, P.R. China
5. Department of Respiratory Medicine, Shangqiu First People's Hospital, Shangqiu, Henan 476100, P.R. China
6. Department of Thoracic and Cardiovascular Surgery, The First Affiliated Hospital of Henan University, Kaifeng, Henan 475000, P.R. China
7. Department of Radiation Oncology, Affiliated Hospital of Hebei University, Baoding, Hebei 071000, P.R. China