1. Division of General Thoracic Surgery, Department of Surgery, Shiga University of Medical Science, Setatsukinowa-cho, Otsu, Shiga, Japan
2. Department of Thoracic Surgery, Mitsubishikyoto Hospital, 1 Katsuragosyo-cho, Nishikyo-ku, Kyoto, Japan
3. Department of Thoracic Surgery, National Hospital Organization Kyoto Medical Center, Fukakusamukaihata-cho, Fushimi-ku, Kyoto, Japan