title: Superiority of lymph node ratio-based staging system for prognostic prediction in 2575 patients with gastric cancer: validation analysis in a large single center.
abstract: This study aimed to evaluate the prognostic significance of node ratio (Nr), the ratio of metastatic to retrieved lymph nodes, and to investigate whether a modified staging system based on Nr can improve prognostic ability for gastric cancer patients following gastrectomy. A total of 2572 patients were randomly divided into training set and validation set, and the cutoff points for Nr were produced using X-tile. The relationships between Nr and other clinicopathologic factors were analyzed, while survival prognostic discriminatory ability and accuracy were compared among different staging systems by AIC and C-index in R program. Patients were categorized into four groups as follows: Nr0, Nr1: 0.00-0.15, Nr2: 0.15-0.40 and Nr3: > 0.40. Nr was significantly associated with clinicopathologic factors including macroscopic type, tumor differentiation, lymphovascular invasion, perineural invasion, tumor size, T stage, N stage and TNM stage. Besides, for all patients, Nr and TNrM staging system showed a smaller AIC and a larger C-index than that of N and TNM staging system, respectively. Moreover, in subgroup analysis for patients with retrieved lymph nodes < 15, Nr was demonstrated to have a smaller AIC and a larger C-index than N staging system. Furthermore, in validation analysis, Nr, categorized by our cutoff points, showed a larger C-index and a smaller AIC value than those produced in previous studies. Nr could be considered as a reliable prognostic factor, even in patients with insufficient (< 15) retrieved lymph nodes, and TNrM staging system may improve the prognostic discriminatory ability and accuracy for gastric cancer patients undergoing radical gastrectomy.
authors.affiliation: Department of Gastrointestinal Surgery, West China Hospital, Sichuan University, Chengdu, Sichuan, China.|Laboratory of Gastric Cancer, State Key Laboratory of Biotherapy/Collaborative Innovation Center of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China.
authors.forename: Lin-Yong
authors.initials: LY
authors.lastname: Zhao
authors.affiliation: Department of Gastrointestinal Surgery, West China Hospital, Sichuan University, Chengdu, Sichuan, China.|Laboratory of Gastric Cancer, State Key Laboratory of Biotherapy/Collaborative Innovation Center of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China.
authors.forename: Chang-Chun
authors.initials: CC
authors.lastname: Li
authors.affiliation: West China School of Pharmacy, Sichuan University, Chengdu, Sichuan, China.
authors.forename: Lu-Yu
authors.initials: LY
authors.lastname: Jia
authors.affiliation: Department of Gastrointestinal Surgery, West China Hospital, Sichuan University, Chengdu, Sichuan, China.|Laboratory of Gastric Cancer, State Key Laboratory of Biotherapy/Collaborative Innovation Center of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China.
authors.forename: Xiao-Long
authors.initials: XL
authors.lastname: Chen
authors.affiliation: Department of Gastrointestinal Surgery, West China Hospital, Sichuan University, Chengdu, Sichuan, China.|Laboratory of Gastric Cancer, State Key Laboratory of Biotherapy/Collaborative Innovation Center of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China.
authors.forename: Wei-Han
authors.initials: WH
authors.lastname: Zhang
authors.affiliation: Department of Gastrointestinal Surgery, West China Hospital, Sichuan University, Chengdu, Sichuan, China.|Laboratory of Gastric Cancer, State Key Laboratory of Biotherapy/Collaborative Innovation Center of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China.
authors.forename: Xin-Zu
authors.initials: XZ
authors.lastname: Chen
authors.affiliation: Department of Gastrointestinal Surgery, West China Hospital, Sichuan University, Chengdu, Sichuan, China.|Laboratory of Gastric Cancer, State Key Laboratory of Biotherapy/Collaborative Innovation Center of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China.
authors.forename: Kun
authors.initials: K
authors.lastname: Yang
authors.affiliation: Department of Gastrointestinal Surgery, West China Hospital, Sichuan University, Chengdu, Sichuan, China.|Laboratory of Gastric Cancer, State Key Laboratory of Biotherapy/Collaborative Innovation Center of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China.
authors.forename: Kai
authors.initials: K
authors.lastname: Liu
authors.affiliation: Department of Gastrointestinal Surgery, West China Hospital, Sichuan University, Chengdu, Sichuan, China.|Laboratory of Gastric Cancer, State Key Laboratory of Biotherapy/Collaborative Innovation Center of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China.
authors.forename: Yi-Gao
authors.initials: YG
authors.lastname: Wang
authors.affiliation: Department of Gastrointestinal Surgery, West China Hospital, Sichuan University, Chengdu, Sichuan, China.|Laboratory of Gastric Cancer, State Key Laboratory of Biotherapy/Collaborative Innovation Center of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China.
authors.forename: Lian
authors.initials: L
authors.lastname: Xue
authors.affiliation: Department of Gastrointestinal Surgery, West China Hospital, Sichuan University, Chengdu, Sichuan, China.
authors.forename: Bo
authors.initials: B
authors.lastname: Zhang
authors.affiliation: Department of Gastrointestinal Surgery, West China Hospital, Sichuan University, Chengdu, Sichuan, China.
authors.forename: Zhi-Xin
authors.initials: ZX
authors.lastname: Chen
authors.affiliation: Department of Gastrointestinal Surgery, West China Hospital, Sichuan University, Chengdu, Sichuan, China.
authors.forename: Jia-Ping
authors.initials: JP
authors.lastname: Chen
authors.affiliation: Department of Gastrointestinal Surgery, West China Hospital, Sichuan University, Chengdu, Sichuan, China.
authors.forename: Zong-Guang
authors.initials: ZG
authors.lastname: Zhou
authors.affiliation: Department of Gastrointestinal Surgery, West China Hospital, Sichuan University, Chengdu, Sichuan, China.|Laboratory of Gastric Cancer, State Key Laboratory of Biotherapy/Collaborative Innovation Center of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China.
authors.forename: Jian-Kun
authors.initials: JK
authors.lastname: Hu
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D005743:Gastrectomy; D006801:Humans; D008197:Lymph Node Excision; D008198:Lymph Nodes / Q000473:pathology; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging / Q000379:methods* / Q000592:standards; D011379:Prognosis; D012189:Retrospective Studies; D013274:Stomach Neoplasms / Q000175:diagnosis* / Q000401:mortality / Q000473:pathology* / Q000601:surgery*; D016019:Survival Analysis
keywords: gastric cancer; lymph node ratio; prediction; staging