1. Department of General Surgery, Taihe Hospital Affiliated with Hubei University of Medicine, Shiyan, Hubei 442000, P.R. China
2. Department of Pathology, Taihe Hospital Affiliated with Hubei University of Medicine, Shiyan, Hubei 442000, P.R. China
3. Department of Pathology, First Affiliated Hospital of Xi'an Medical University, Xi'an, Shanxi 710000, P.R. China