1. Department of Gastroenterology, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, P.R. China
2. Department of Pathology, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, P.R. China
3. Department of Oncology, The Fifth Hospital of Wuhan, Wuhan, Hubei 430050, P.R. China