1. Division of Respiratory Medicine, Department of Internal Medicine, Jichi Medical University Hospital, 3311-1 Yakushi-ji, Shimotsuke-shi, Tochigi-ken, 329-0431, Japan
2. Department of Respiratory Medicine, Jichi Medical University Saitama Medical Center, Saitama, Japan
3. Department of Clinical Oncology, Jichi Medical University Hospital, 3311-1 Yakushi-ji, Shimotsuke-shi, Tochigi-ken, 329-0431, Japan