Meta-Analysis
Copyright ©The Author(s) 2015. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Dec 21, 2015; 21(47): 13374-13385
Published online Dec 21, 2015. doi: 10.3748/wjg.v21.i47.13374
Endoscopic stenting for inoperable malignant biliary obstruction: A systematic review and meta-analysis
Leonardo Zorrón Pu, Eduardo Guimarães Hourneaux de Moura, Wanderley Marques Bernardo, Felipe Iankelevich Baracat, Ernesto Quaresma Mendonça, André Kondo, Gustavo Oliveira Luz, Carlos Kiyoshi Furuya Júnior, Everson Luiz de Almeida Artifon
Leonardo Zorrón Pu, Eduardo Guimarães Hourneaux de Moura, Felipe Iankelevich Baracat, Ernesto Quaresma Mendonça, André Kondo, Gustavo Oliveira Luz, Carlos Kiyoshi Furuya Júnior, Everson Luiz de Almeida Artifon, Gastrointestinal Endoscopy Division, Department of Gastroenterology, Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo, Sao Paulo 05403-000, Brazil
Wanderley Marques Bernardo, Guidelines Program Coordinator, Brazilian Medical Association, Sao Paulo 01333-001, Brazil
Author contributions: Zorrón Pu L did the electronic database search, revised and read all selected studies, analysed all data and graphs, wrote the paper; de Moura EGH scientifically coordinated the study; Bernardo WM performed a paired database search, peer-reviewed the paper and scientifically coordinated the study (biostatistics and evidence-based guidance); Baracat FI helped with the development of tables and graphs and, through weekly reunions, provided cues for improvements; Mendonça EQ helped with the development of tables and graphs and, through weekly reunions, provided cues for improvements; Kondo A helped with the revision of the article; Luz GO provided technical observations and evaluated bias and applicability of the therapies; Furuya Júnior CK provided technical observations and evaluated bias and applicability of the therapies; Artifon ELA scientifically coordinated the study; all authors reviewed and approved the final manuscript as submitted.
Conflict-of-interest statement: All the authors declare that they have no competing interests.
Data sharing statement: The technical appendix, statistical code, and dataset are available from the corresponding author at leozorron@gmail.com. No additional data are available.
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: Leonardo Zorrón Pu, MD, Fellow of the Gastrointestinal Endoscopy Division, Department of Gastroenterology, Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo, Sao Paulo 05403-000, Brazil. leozorron@gmail.com
Telephone: +55-11-26616467 Fax: +55-11-26616467
Received: May 21, 2015
Peer-review started: May 23, 2015
First decision: July 10, 2015
Revised: July 22, 2015
Accepted: September 28, 2015
Article in press: September 30, 2015
Published online: December 21, 2015
Abstract

AIM: To analyze through meta-analyses the benefits of two types of stents in the inoperable malignant biliary obstruction.

METHODS: A systematic review of randomized clinical trials (RCT) was conducted, with the last update on March 2015, using EMBASE, CINAHL (EBSCO), MEDLINE, LILACS/CENTRAL (BVS), SCOPUS, CAPES (Brazil), and gray literature. Information of the selected studies was extracted in sight of six outcomes: primarily regarding dysfunction, complication and re-intervention rates; and secondarily costs, survival, and patency time. The data about characteristics of trial participants, inclusion and exclusion criteria and types of stents were also extracted. The bias was mainly assessed through the JADAD scale. This meta-analysis was registered in the PROSPERO database by the number CRD42014015078. The analysis of the absolute risk of the outcomes was performed using the software RevMan, by computing risk differences (RD) of dichotomous variables and mean differences (MD) of continuous variables. Data on RD and MD for each primary outcome were calculated using the Mantel-Haenszel test and inconsistency was qualified and reported in χ2 and the Higgins method (I2). Sensitivity analysis was performed when heterogeneity was higher than 50%, a subsequent assay was done and other findings were compiled. Student’s t-test was used for the comparison of weighted arithmetic means regarding secondary outcomes.

RESULTS: Initial searching identified 3660 studies; 3539 were excluded through title, repetition, and/or abstract, while 121 studies were fully assessed and were excluded mainly because they did not compare self-expanding metal stents (SEMS) and plastic stents (PS), leading to thirteen RCT selected, with 13 articles and 1133 subjects meta-analyzed. The mean age was 69.5 years old, that were affected mostly by bile duct (proximal) and pancreatic tumors (distal). The preferred SEMS diameter used was the 10 mm (30 Fr) and the preferred PS diameter used was 10 Fr. In the meta-analysis, SEMS had lower overall stent dysfunction compared to PS (21.6% vs 46.8%, P < 0.00001) and fewer re-interventions (21.6% vs 56.6%, P < 0.00001), with no difference in complications (13.7% vs 15.9%, P = 0.16). In the secondary analysis, the mean survival rate was higher in the SEMS group (182 d vs 150 d, P < 0.0001), with a higher patency period (250 d vs 124 d, P < 0.0001) and a lower cost per patient (4193.98 vs 4728.65 Euros, P < 0.0985).

CONCLUSION: SEMS are associated with lower stent dysfunction, lower re-intervention rates, better survival, and higher patency time. Complications and costs showed no difference.

Keywords: Biliary tract neoplasms, Malignant biliary obstruction, Jaundice, Palliative care, Endoscopic retrograde cholangiopancreatography, Stent, Systematic review, Meta-analysis

Core tip: Endoscopic stenting is accepted worldwide as the first choice palliative treatment for malignant biliary obstruction. There are still two types of materials currently being used, which are plastic and metal. Therefore, many doubts are raised as to which one is the most beneficial to the patient. This review gathers the highest quality information available about these two types of stent, giving information in regards to dysfunction, complication, re-intervention rates, costs, survival, and patency time; and intend to help handle clinical practice nowadays, especially in countries where the availability of metallic stents is scarce and cannot be offered to all patients.