1. Department of Abdominal Oncology; Zhejiang Cancer Hospital; Hangzhou 310022 Zhejiang P. R. China
2. School of Medicine; Zhejiang University; Hangzhou 310058 Zhejiang P. R. China
3. Department of Radiotherapy; Zhejiang Cancer Hospital; Hangzhou 310022 Zhejiang P. R. China
4. Department of Pathology; Zhejiang Cancer Hospital; Hangzhou 310022 Zhejiang P. R. China