Guo-Ming Chen1, Run-Cong Nie1, Ying-Bo Chen2. 1. State Key Laboratory of Oncology in South China, Department of Gastric Surgery, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, Guangdong, China. 2. State Key Laboratory of Oncology in South China, Department of Gastric Surgery, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, Guangdong, China. surgeoncyb@163.com.