1. Department of Digestive, China-Japan Union Hospital, Jilin University, Changchun, Jilin 130033, China
2. Department of Radiology and Bio-X Program, Molecular Imaging Program at Stanford (MIPS), Canary Center at Stanford for Cancer Early Detection, 1201 Welch Road, Lucas Center, P095, Stanford University, Stanford, CA 94305, USA
3. Department of Surgery, Asian Liver Center, Stanford University School of Medicine, Stanford University, Stanford, CA 94305, USA