1. Department of Hepatobiliary Surgery, Xiang’an Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, Fujian 361102, P. R. China
2. Xiamen University Research Center of Retroperitoneal Tumor Committee of Oncology Society of Chinese Medical Association, Xiamen University, Xiamen, Fujian 361102, P. R. China
3. Department of Hepatobiliary Surgery, Guizhou Provincial People’s Hospital, Guiyang, Guizhou 550002, P. R. China
4. Surgery department, Affiliated Fuzhou First Hospital of Fujian Medical University, Fuzhou, Fujian 350009, P. R. China
5. Cancer Research Center, School of Medicine, Xiamen University, Xiamen, Fujian 361102, P. R. China