1. Department of Oncology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan Province, China
2. Department of Pathology, The Norwegian Radium Hospital, Oslo University Hospital, University of Oslo, Montebello, Oslo, Norway
3. Department of Pathology, The Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, Montebello, Oslo, Norway
4. Institute of Clinical Medicine, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan Province, China
5. Department of Anatomy, Histology and Embryology, Peking University Health Science Center, Peking University, Beijing, China
6. Department of Surgery, the Norwegian Radium Hospital, Oslo University Hospital, University of Oslo, Oslo, Norway