1. Department of Pathology Tokyo Medical and Dental University Tokyo Japan
2. Department of Surgery JA Toride Medical Center Ibaraki Japan
3. Baraki‐Nakayama Clinic Chiba Japan
4. Department of Radiology JA Toride Medical Center Ibaraki Japan
5. Department of Pathology JA Toride Medical Center Ibaraki Japan
6. Department of Human Pathology Tokyo Medical and Dental University Tokyo Japan