Meta-Analysis
Copyright ©The Author(s) 2015. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Mar 7, 2015; 21(9): 2807-2815
Published online Mar 7, 2015. doi: 10.3748/wjg.v21.i9.2807
Prognostic significance of neutrophil to lymphocyte ratio in pancreatic cancer: A meta-analysis
Jian-Jun Yang, Zhi-Gao Hu, Wu-Xiang Shi, Te Deng, Song-Qing He, Sheng-Guang Yuan
Jian-Jun Yang, Zhi-Gao Hu, Song-Qing He, Sheng-Guang Yuan, Laboratory of Hepatobiliary and Pancreatic Surgery, Affiliated Hospital of Guilin Medical University, Guilin 541001, Guangxi Zhuang Autonomous Region, China
Wu-Xiang Shi, Te Deng, Department of Epidemiology and Biostatistics, School of Public Health, Guilin Medical University, Guilin 541004, Guangxi Zhuang Autonomous Region, China
Song-Qing He, Guangxi Key Laboratory of Molecular Medicine in Liver Injury and Repair, Guilin 541001, Guangxi Zhuang Autonomous Region, China
Author contributions: Yang JJ and Hu ZG performed the research and wrote the paper; He SQ and Yuan SG designed the study; Shi WX and Deng T analyzed the data; and Yang JJ and Hu ZG contributed equally to this work.
Supported by Natural Science Foundation of Guangxi Province, No. 2013GXNSFAA019196 (in part); and the Science and Technology Planning Project of Guilin City, No. 20100128-5.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Song-Qing He, MD, Laboratory of Hepatobiliary and Pancreatic Surgery, Affiliated Hospital of Guilin Medical University, Guilin 541001, Guangxi Zhuang Autonomous Region, China. dr_hesongqing@163.com
Telephone: +86-773-2809503 Fax: +86-773-2862270
Received: July 1, 2014
Peer-review started: July 2, 2014
First decision: July 21, 2014
Revised: August 8, 2014
Accepted: October 15, 2014
Article in press: October 15, 2014
Published online: March 7, 2015
Processing time: 251 Days and 3.6 Hours
Abstract

AIM: To conduct a meta-analysis evaluating the association between the peripheral blood neutrophil to lymphocyte ratio (NLR) and the outcome of patients with pancreatic cancer.

METHODS: Studies evaluating the relationship between the peripheral blood NLR and outcome of patients with pancreatic cancer published up to May 2014 were searched using electronic databases, including PubMed, Web of Science, Embase and Ovid. A meta-analysis was performed to pool the hazard ratios (HRs) or odds ratios (ORs) and their 95% confidence intervals (CIs) using either a fixed-effects model or a random-effects model to quantitatively assess the prognostic value of NLR and its association with clinicopathological parameters.

RESULTS: Eleven studies containing a total of 1804 patients were eligible according to our selection criteria, and combined hazard ratios indicated that high NLR was a poor prognostic marker for pancreatic cancer patients because it had an unfavorable impact on the overall survival (OS) (HR = 2.61, 95%CI: 1.68-4.06, P = 0.000) and cancer specific survival (HR = 1.66, 95%CI: 1.08-2.57, P = 0.021). Subgroup analysis revealed that high NLR was associated with poor OS in patients with mixed treatment (HR = 4.36, 95%CI: 2.50-7.61, P = 0.000), chemotherapy (HR = 2.08, 95%CI: 1.49-2.9, P = 0.000), or surgical resection (HR = 1.2, 95%CI: 1.00-1.44, P = 0.048). Additionally, high NLR was significantly correlated with tumor metastasis (OR = 1.69, 95%CI: 1.10-2.59, P = 0.016), poor tumor differentiation (OR = 2.75, 95%CI: 1.19-6.36, P = 0.016), poor performance status (OR = 2.56, 95%CI: 1.63-4.03, P = 0.000), high cancer antigen 199 (OR = 2.62, 95%CI: 1.49-4.60, P = 0.000), high C-reactive protein (OR = 4.32, 95%CI: 2.71-6.87, P = 0.000), and low albumin (OR = 3.56, 95%CI: 1.37-9.27, P = 0.009).

CONCLUSION: High peripheral blood NLR suggested a poor prognosis for patients with pancreatic cancer, and it could be a novel marker of survival evaluation and could help clinicians develop therapeutic strategies for pancreatic cancer patients.

Keywords: Neutrophil to lymphocyte ratio; Pancreatic cancer; Overall survival; Cancer specific survival; Clinicopathological features; Meta-analysis

Core tip: We performed a meta-analysis to evaluate the relationship between the peripheral blood neutrophil to lymphocyte ratio (NLR) and outcome of patients with pancreatic cancer. The results showed that high NLR was a poor prognostic marker and high NLR was associated with poor overall survival in patients with mixed treatment, chemotherapy, or surgical resection. Furthermore, high NLR was significantly correlated with tumor metastasis, poor tumor differentiation, poor performance status, high carbohydrate antigen 199, high C-reactive protein, and low albumin. This is the first comprehensive and detailed analysis for evaluating the prognostic value of the NLR and its association with the clinicopathological features for pancreatic cancer patients. NLR might be a novel marker of the survival evaluation for pancreatic cancer patients.