1. Department of Gastrointestinal Surgery; Peking University People's Hospital; Beijing China
2. Laboratory of Surgical Oncology; Peking University People's Hospital; Beijing China
3. Department of Human Anatomy, Histology and Embryology; Peking University Health Science Center; Beijing China
4. Department of Pathology; Peking University People's Hospital; Beijing China
5. Department of Pathology; Peking University Health Science Center; Beijing China