Meta-Analysis
Copyright ©The Author(s) 2019. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Clin Cases. Oct 26, 2019; 7(20): 3247-3258
Published online Oct 26, 2019. doi: 10.12998/wjcc.v7.i20.3247
Prognostic significance of malignant ascites in gastric cancer patients with peritoneal metastasis: A systemic review and meta-analysis
Ling-Nan Zheng, Feng Wen, Ping Xu, Shuang Zhang
Ling-Nan Zheng, Shuang Zhang, Department of Biotherapy, State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Chengdu 610041, Sichuan Province, China
Feng Wen, Department of Abdominal Oncology, State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Chengdu 610041, Sichuan Province, China
Ping Xu, Sichuan University Library, Sichuan University, Chengdu 610041, Sichuan Province, China
Author contributions: Zheng LN acquired, analyzed, and interpreted the data and drafted the manuscript; Wen F analyzed and interpreted the data and revised the manuscript; Xu P acquired the data and drafted the manuscript; Zhang S conceived and designed the study and critically revised the manuscript; all authors approved the final manuscript.
Supported by the National Natural Science Foundation of China, No. 81672577.
Conflict-of-interest statement: The authors deny any conflicts of interest.
PRISMA 2009 Checklist statement: The authors have read the PRISMA 2009 Checklist, and the manuscript was prepared and revised according to the PRISMA 2009 Checklist.
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/
Corresponding author: Shuang Zhang, MD, PhD, Associate Professor, Department of Biotherapy, State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, 4 Keyuan Road, Gaopeng Street, Chengdu 610041, Sichuan Province, China. shuang.zhang@scu.edu.cn
Telephone: +86-28-85164063 Fax: +86-28-85164060
Received: June 12, 2019
Peer-review started: June 12, 2019
First decision: July 21, 2019
Revised: August 16, 2019
Accepted: September 9, 2019
Article in press: September 9, 2019
Published online: October 26, 2019
Processing time: 136 Days and 14.7 Hours
ARTICLE HIGHLIGHTS
Research background

Gastric cancer (GC) is the fifth most common malignancy globally. The majority of patients with GC are diagnosed at a relatively advanced stage, some even with metastatic disease. For patients with GC, the most life-threatening type of metastasis is peritoneal metastasis (PM), which often accompanies malignant ascites. GC patients with PM and malignant ascites tend to have a worse prognosis.

Research motivation

Recent evidence indicates that malignant ascites may be associated with the high malignancy and poor prognosis of GC with PM, but no robust consensus has been reached until now.

Research objectives

We conducted this meta-analysis to evaluate the prognostic significance of ascites in GC patients with PM.

Research methods

Two independent authors conducted database searches. The searches were performed in the EMBASE, PubMed, and Cochrane Library databases, and the terms used to search included stomach neoplasms, GC, ascites, peritoneal effusion, survival, and survival analysis. RevMan 5 software was used for this meta-analysis. The hazard ratio (HR) with a 95%CI served as the appropriate summary statistic. Three pairs of comparisons measuring survival were made: (1) Patients with ascites vs those without ascites; (2) Patients with massive ascites vs those with mild to moderate ascites; and (3) Patients with massive ascites vs those with no to moderate ascites.

Research results

Fourteen articles including fifteen studies were considered in the final analysis. Among them, nine studies assessed the difference in prognosis between patients with and without malignant ascites. A pooled HR of 1.63 (95% CI: 1.47-1.82, P < 0.00001) indicated that GC patients with malignant ascites had a relatively poor prognosis compared to patients without ascites. We also found that the prognosis of GC patients with malignant ascites was related to the volume of ascites in the six other studies.

Research conclusions

GC patients with malignant ascites tend to have a worse prognosis, and the volume of ascites has an impact on GC outcomes.

Research perspectives

To the best of our knowledge, this is the first systematic meta-analysis to demonstrate the prognostic significance of malignant ascites in GC patients with PM. Because most of the studies included in this meta-analysis are retrospective studies, some confounding factors exist. Higher quality prospective studies with more patients will be necessary to validate malignant ascites as a predictive marker of poor outcome.