1 Department of General Surgery, The First Affiliated Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, China.
2 Department of Pathology, The First Affiliated Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, China.
3 Department of Gastroenterology, The First Affiliated Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, China; Department of Gastroenterology, The Third Clinical Medical College, Fujian Medical University, Fuzhou, China.
4 Department of Gastroenterology, The First Affiliated Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, China; Department of Gastroenterology, The Third Clinical Medical College, Fujian Medical University, Fuzhou, China. Electronic address: hwf0625@xmu.edu.cn.