Positive relationship between number of negative lymph nodes and duration of gallbladder cancer cause-specific survival after surgery

Jin-Yong Lin,1,2,* Dou-Sheng Bai,1,* Bao-Huan Zhou,1,2,* Ping Chen,1 Jian-Jun Qian,1 Sheng-Jie Jin,1 Guo-Qing Jiang1 1Department of Hepatobiliary Surgery, Clinical Medical College, Yangzhou University, Yangzhou, China; 2Department of Hepatobiliary Surgery, The Second Clinical College, Dalian Medical University, Dalian, China *These authors contributed equally to this work Background: Although the prognostic implications of negative lymph nodes (NLNs) has been reported for a variety of tumors, little information has been published about the NLNs in gallbladder cancer (GBC).Patients and methods: In this study, clinicopathological characteristics and survival times of patients who had undergone surgery for GBC were collected from the Surveillance, Epidemiology, and End Results Program-registered TNM stage database and analyzed. Univariate and multivariate Cox proportional hazards models were used to identify the predictors of survival.Results: It was found that a cutoff of one to two NLNs is optimal when assessing the association with survival, survival rates being consistently better with two or more NLNs than with fewer than two. This optimal cutoff value of 2 was identified as an independent prognostic factor by univariate and multivariate analyses (all P