1. Department of Hepatobiliary Pancreatic Surgery, Changhai Hospital, Navy Military Medical University (Second Military Medical University) , Shanghai , China
2. Department of General Surgery, Naval Medical Centre of People’s Liberation Army , Shanghai , China
3. Department of Hepatobiliary Surgery, First People’s Hospital of Jining , Jining , China
4. Department of Pathology, Changhai Hospital, Naval Military Medical University (Second Military Medical University) , Shanghai , China