Research Report
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World J Gastroenterol. Apr 7, 2014; 20(13): 3640-3648
Published online Apr 7, 2014. doi: 10.3748/wjg.v20.i13.3640
Prognostic value of number of examined lymph nodes in patients with node-negative gastric cancer
Xu-Guang Jiao, Jing-Yu Deng, Ru-Peng Zhang, Liang-Liang Wu, Li Wang, Hong-Gen Liu, Xi-Shan Hao, Han Liang
Xu-Guang Jiao, Jing-Yu Deng, Ru-Peng Zhang, Liang-Liang Wu, Li Wang, Hong-Gen Liu, Xi-Shan Hao, Han Liang, Key Laboratory of Cancer Prevention and Therapy, Department of Gastrointestinal Oncology, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer, Tianjin 300060, China
Author contributions: Jiao XY, Deng JY, Liang H performed the majority of the study; Jiao XG, Deng JY, Zhang RP, Wu LL, Wang L and Liu HG designed the study and analyzed data; Jiao XG, Deng JY wrote the manuscript; Hao XS and Liang H revised the manuscript.
Supported by A grant from the National Basic Research Program of China (973 Program), No. 2010CB529301
Correspondence to: Han Liang, MD, Key Laboratory of Cancer Prevention and Therapy, Department of Gastrointestinal Oncology, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer, Huanhuxi Road, Hexi District, Tianjin 300060, China. tjlianghan022@sohu.com
Telephone: +86-22-23340123 Fax: +86-22-23340123
Received: August 7, 2013
Revised: November 9, 2013
Accepted: December 12, 2013
Published online: April 7, 2014
Abstract

AIM: To elucidate the potential impact of examined lymph nodes (eLNs) on long-term survival of node-negative gastric cancer patients after curative surgery.

METHODS: A total of 497 node-negative gastric cancer patients who underwent curative gastrectomy between January 2000 and December 2008 in our center were enrolled in this study. Patients were divided into 4 groups according to eLNs through cut-point analysis. Clinicopathological features were compared between ≤ 15 eLNs group and > 15 eLNs group and potential prognostic factors were analyzed. The Log-rank test was used to assess statistical differences between the groups. Independent prognostic factors were identified using the Cox proportional hazards regression model. Stratified analysis was performed to investigate the impact of eLNs on patient survival in each stage. Overall survival was also compared among the four groups. Finally, we explored the recurrent sites associated with eLNs.

RESULTS: Patients with eLNs > 15 had a better survival compared with those with eLNs ≤ 15 for the entire cohort. By the multivariate survival analysis, we found that the depth of invasion and the number of eLNs were the independent predictors of overall survival (OS) of patients with node-negative gastric cancer. According to the cut-point analysis, T2-T4 patients with 11-15 eLNs had a significantly longer mean OS than those with 4-10 eLNs or 1-3 eLNs. Patients with ≤ 15 eLNs were more likely to experience locoregional and peritoneal recurrence than those with > 15eLNs.

CONCLUSION: Number of eLNs could predict the prognosis of node-negative gastric cancer, and dissection of > 15 eLNs is recommended during lymphadenectomy so as to improve the long-term survival.

Keywords: Gastric carcinoma, Examined lymph nodes, Node-negative, Prognosis

Core tip: The number of metastatic lymph nodes has been shown to be associated with prognosis in gastric cancer patients. In this study, we found that the overall survival of node-negative gastric cancer patients was significantly affected by examined lymph nodes (eLNs), and number of eLNs was an independent prognostic factor in multivariate analysis. Dissection of > 15 eLNs could reduce locoregional and peritoneal recurrence. We suggest that over 15 lymph nodes should be examined to improve the long-term outcome of node-negative gastric cancer patients following curative gastrectomy.