Department of General Surgery, PLA 306 Clinical Hospital of Anhui Medical University, Beijing, 230000, China. Department of General Surgery, PLA 306 Teaching Hospital of Peking University Health Science Center, Beijing, 100101, China. The Center for Hepatopancreatobiliary Diseases, Beijing Tsinghua Changgung Hospital, Tsinghua University, Beijing, 102218, China. Department of General Surgery, 306 Hospital of PLA, Beijing, 100101, China. Medicine and Experimental Research Center, 306 Hospital of PLA, Beijing, 100101, China. Department of Pathology, 306 Hospital of PLA, Beijing, 100101, China. Department of General Surgery, 306 Hospital of PLA, Beijing, 100101, China. dryancui@163.com.