Meta-Analysis
Copyright ©The Author(s) 2020. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastrointest Endosc. Aug 16, 2020; 12(8): 231-240
Published online Aug 16, 2020. doi: 10.4253/wjge.v12.i8.231
Endoscopic ultrasound-guided fiducial marker placement in pancreatic cancer: A systematic review and meta-analysis
Jaymon B Patel, Vakya Revanur, David G Forcione, Matthew L Bechtold, Srinivas R Puli
Jaymon B Patel, Srinivas R Puli, Department of Gastroenterology, University of Illinois College of Medicine at Peoria, Peoria, IL 61637, United States
Vakya Revanur, Department of Internal Medicine, University of Illinois College of Medicine at Peoria, Peoria, IL 61637, United States
David G Forcione, Department of Gastroenterology, Massachusetts General Hospital, Boston, MA 02114, United States
Matthew L Bechtold, Department of Gastroenterology, University of Missouri, Columbia, MO 65203, United States
Author contributions: Patel JB contributed to the data collection, initial draft of manuscript, discussion, revisions; Revanur V contributed to data collection; Forcione DG contributed to critical review of manuscript, drafting revisions; Bechtold ML contributed to critical review of manuscript, drafting revisions; Puli SR contributed to conceptualizing study, data analysis and critical review of manuscript.
Conflict-of-interest statement: The authors declare that they have no conflict 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 that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (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: Jaymon B Patel, MD, Assistant Professor, Department of Gastroenterology, University of Illinois College of Medicine at Peoria, 530 NE Glen Oak Ave, Peoria, IL 61637, United States. jaymon.b.patel@osfhealthcare.org
Received: April 2, 2020
Peer-review started: April 2, 2020
First decision: April 22, 2020
Revised: May 9, 2020
Accepted: July 19, 2020
Article in press: July 19, 2020
Published online: August 16, 2020
ARTICLE HIGHLIGHTS
Research background

Fiducial marker placement for pancreatic cancer (PC) has demonstrated utility as a landmark to target radiotherapy with or without chemotherapy. Historically, these have been placed surgically or percutaneously, each with their own limitations. More recently, endoscopic ultrasound (EUS) guided placement has been undertaken.

Research motivation

PC remains a leading cause of cancer related mortality owing to its advanced stage at time of symptom development and subsequent inability to undergo surgery for definitive treatment. EUS has conferred diagnostic and therapeutic benefits with respect to tissue sampling and celiac plexus block. Given the inability to target deep structures with percutaneous fiducial marker placement and invasive nature of surgical fiducial marker placement, EUS has emerged as a potential marker placement modality that can overcome the aforementioned challenges.

Research objectives

We sought to evaluate the safety, efficacy, and feasibility of EUS-guided fiducial marker placement for PC patients anticipated to undergo radiotherapy via meta-analysis of available case series as no randomized clinical trials exist. The derived data has the potential to alter the clinical course of patients.

Research methods

Articles were searched in Medline, PubMed, and Ovid journals and ultimately, 11 studies met inclusion criteria and underwent data extraction (n = 820). Data extracted from included studies then underwent analysis by performing pooled estimates by Mantel-Haenszel (fixed effects model) and DerSimonian Laird method (random effects model). Confidence intervals (CIs) were computed using the F distribution method. Forrest plots were constructed to demonstrate the point estimates in each study, with respect to the summary pooled estimate. Heterogeneity was assessed using Cochran’s Q test based upon inverse variance weights. The Egger and Begg-Mazumdar bias indicators were used to assess for publication and selection bias, and funnel plots were generated for assessment of interobserver variability.

Research results

Of the meta-analysis of 820 patients who underwent fiducial marker placement under EUS guidance, technical success of fiducial marker placement pooled proportion was 96.27% (95%CI: 95.35-97.81). EUS-guided placement was well tolerated with adverse event pooled proportion 4.85% (95%CI: 3.04-7.03). Given the need for the markers to serve as stationary landmarks to facilitate image-guided radiation therapy, post-procedural migration of fiducials is of significance. Pooled proportion of fiducial marker migration was 4.33% (95%CI: 2.45-6.71).

Research conclusions

Our meta-analysis demonstrated high technical success rates of EUS-guided fiducial placement, low rates of complete fiducial marker migration, and low adverse event rates demonstrating its utility as a fiducial marker placement modality. Further studies evaluating for improved outcomes in image-guided radiotherapy or improved modality are needed.

Research perspectives

EUS-guided fiducial placement is demonstrated to be a safe, efficacious, and feasible modality of marker placement. In addition, the ability to perform concomitant diagnostic procedures, such as fine needle biopsy, as well as therapeutic procedures, such as celiac plexus block, may hasten treatment and improve quality of life.