1. Department of Thoracic Surgery, Tokyo Medical University Ibaraki Medical Center, Ami-machi, Ibaraki, Japan
2. Department of Thoracic Surgery, Tokyo Medical University Hachioji Medical Center, Hachioji, Tokyo, Japan
3. Department of Surgery, Migita Hospital, Hachioji, Tokyo, Japan
4. Department of Surgery, Tokyo Medical University, Tokyo, Japan
5. Department of Diagnostic Pathology, Tokyo Medical University Hachioji Medical Center, Hachioji, Tokyo, Japan