Correspondence to: Chun-You Wang, Department of Pancreatic Surgery, Xiehe Hospital, Tongii Medical College, Huazhong University of Sciecne and Technology, 1277 Jiefang Road, Wuhan 430022, Hubei Province, China. dryzy@163.com Telephone: +86-27-85351621 Fax: +86-27-85351673