1 Department of Gastrointestinal Surgery, West China Hospital, Sichuan University, Chengdu, China; Department of General Surgery, West China-Shangjin Hospital/Chengdu Shangjin Nanfu Hospital, Sichuan University, Chengdu, China. Electronic address: maqing4s@163.com.
2 Department of Gastrointestinal Surgery, West China Hospital, Sichuan University, Chengdu, China.
3 Department of Thyroid and Parathyroid Surgery, West China Hospital, Sichuan University, Chengdu, China.