1. Cancer Treatment Center, Kansai Medical University Hospital, 2-3-1, Shinmachi, Hirakata 573-1191, Osaka, Japan
2. Department of Thoracic Oncology, Kansai Medical University, 2-3-1, Shinmachi, Hirakata 573-1191, Osaka, Japan
3. Department of Gastroenterology, Kansai Medical University, 2-3-1, Shinmachi, Hirakata 573-1191, Osaka, Japan
4. Department of Surgery, Kansai Medical University, 2-3-1, Shinmachi, Hirakata 573-1191, Osaka, Japan
5. Division of Surgical Oncology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA