1. Department of Respiratory Medicine, Sapporo Kosei General Hospital, Japan
2. Department of Respiratory Medicine and Allergology, Sapporo Medical University School of Medicine, Japan
3. Respiratory Medicine, Hakodate Municipal Hospital, Japan
4. Department of Pathology, Sapporo Medical University School of Medicine, Japan
5. Department of Surgical Pathology, Sapporo Medical University School of Medicine, Japan