1. Department of Gastric Surgery, Sun Yat-sen University Cancer Center, Guangzhou, Guangdong, P. R. China
2. State Key Laboratory of Oncology in South China, Guangzhou, Guangdong, P. R. China
3. Collaborative Innovation Center for Cancer Medicine, Guangzhou, Guangdong, P. R. China
4. Department of Gastric Surgery, The 6th Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, P. R. China