1. Department of Biliary Surgery, West China Hospital, Sichuan University , Chengdu 610041 , Chengdu China
2. Laboratory of Pathology, West China Hospital, Sichuan University , Chengdu 610041 , Chengdu China
3. Department of Pathology, West China Hospital, Sichuan University , Chengdu 610041 , Chengdu China