1. Department of Thoracic Surgery, Tsuchiura Kyodo General Hospital, Tsuchiura, Ibaraki 3000028, Japan
2. Divisions of Thoracic Surgery, Hitachi General Hospital, Hitachi, Ibaraki 3170077, Japan
3. Division of Thoracic Surgery, Ibarakihigashi Hospital, Tokai‑mura, Ibaraki 3191113, Japan
4. Division of Respiratory Medicine and Thoracic Surgery, Mito Medical Center, University of Tsukuba‑Mito Kyodo General Hospital, Mito, Ibaraki 3100015, Japan
5. Division of Thoracic Surgery, Mito Medical Center, Mito, Ibaraki 3113193, Japan
6. Respiratory Center, Ibaraki Prefectural Central Hospital, Kasama, Ibaraki 3091703, Japan
7. Division of Thoracic Surgery, Tsukuba Memorial Hospital, Tsukuba, Ibaraki 3002622, Japan
8. Division of Thoracic Surgery, Ibaraki Seinan Medical Center Hospital, Sakai‑machi, Ibaraki 3060433, Japan
9. Division of Thoracic Surgery, Tsukuba Medical Center Hospital, Tsukuba, Ibaraki 3058558, Japan
10. Faculty of Clinical Medicine, University of Tsukuba, Tsukuba, Ibaraki 3058575, Japan
11. Division of Thoracic Surgery, Tokyo Medical University, Ibaraki Medical Center, Ami‑machi, Ibaraki 3113193, Japan