Retrospective Study
Copyright ©The Author(s) 2017. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Sep 14, 2017; 23(34): 6273-6280
Published online Sep 14, 2017. doi: 10.3748/wjg.v23.i34.6273
Predictive factors for the failure of endoscopic stent-in-stent self-expandable metallic stent placement to treat malignant hilar biliary obstruction
Mitsuru Sugimoto, Tadayuki Takagi, Rei Suzuki, Naoki Konno, Hiroyuki Asama, Ko Watanabe, Jun Nakamura, Hitomi Kikuchi, Yuichi Waragai, Mika Takasumi, Yuki Sato, Takuto Hikichi, Hiromasa Ohira
Mitsuru Sugimoto, Tadayuki Takagi, Rei Suzuki, Naoki Konno, Hiroyuki Asama, Ko Watanabe, Jun Nakamura, Hitomi Kikuchi, Yuichi Waragai, Mika Takasumi, Yuki Sato, Hiromasa Ohira, Department of Gastroenterology, Fukushima Medical University, School of Medicine, Fukushima 960-1247, Japan
Ko Watanabe, Jun Nakamura, Hitomi Kikuchi, Takuto Hikichi, Department of Endoscopy, Fukushima Medical University Hospital, Fukushima 960-1247, Japan
Author contributions: Sugimoto M designed research; Sugimoto M and Takagi T performed research; Sugimoto M, Takagi T and Ohira H analysed data; Sugimoto M, Takagi T and Ohira H wrote the paper; Suzuki R, Konno N, Asama H, Watanabe K, Nakamura J, Kikuchi H, Waragai Y, Takasumi M, Sato Y and Hikichi T provided clinical advice; Hikichi T and Ohira H supervised the report.
Supported by Department of Gastroenterology, Fukushima Medical University, School of Medicine.
Institutional review board statement: This study was reviewed and approved by the Ethics Committee of the Fukushima Medical University Hospital.
Informed consent statement: Patients were not required to give informed consent for this study because the analysis used anonymous clinical data that were obtained after each patient agreed to treatment by written consent. For full disclosure, the details of the study are published on the home page of Fukushima Medical University.
Conflict-of-interest statement: We have no financial relationships to disclose.
Data sharing statement: 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: Tadayuki Takagi, Associate Professor, Department of Gastroenterology and Rheumatology, Fukushima Medical University, 1 Hikarigaoka, Fukushima 960-1247, Japan. daccho@fmu.ac.jp
Telephone: +81-24-5471202 Fax: +81-24-5472055
Received: May 16, 2017
Peer-review started: May 17, 2017
First decision: June 22, 2017
Revised: July 4, 2017
Accepted: August 8, 2017
Article in press: August 8, 2017
Published online: September 14, 2017
Abstract
AIM

To investigate the factors predictive of failure when placing a second biliary self-expandable metallic stents (SEMSs).

METHODS

This study evaluated 65 patients with an unresectable malignant hilar biliary obstruction who were examined in our hospital. Sixty-two of these patients were recruited to the study and divided into two groups: the success group, which consisted of patients in whom a stent-in-stent SEMS had been placed successfully, and the failure group, which consisted of patients in whom the stent-in-stent SEMS had not been placed successfully. We compared the characteristics of the patients, the stricture state of their biliary ducts, and the implemented endoscopic retrograde cholangiopancreatography (ERCP) procedures between the two groups.

RESULTS

The angle between the target biliary duct stricture and the first implanted SEMS was significantly larger in the failure group than in the success group. There were significantly fewer wire or dilation devices (ERCP catheter, dilator, or balloon catheter) passing the first SEMS cell in the failure group than in the success group. The cut-off value of the angle predicting stent-in-stent SEMS placement failure was 49.7 degrees according to the ROC curve (sensitivity 91.7%, specificity 61.2%). Furthermore, the angle was significantly smaller in patients with wire or dilation devices passing the first SEMS cell than in patients without wire or dilation devices passing the first SEMS cell.

CONCLUSION

A large angle was identified as a predictive factor for failure of stent-in-stent SEMS placement.

Keywords: Endoscopic stent-in-stent self-expandable metallic stent placement, Predictive factor, Endoscopic retrograde cholangiopancreatography, Malignant hilar biliary obstruction, Self-expandable metallic stent

Core tip: We investigated the factors predictive of failure when placing multiple endoscopic self-expandable metallic stents (SEMSs) to relieve a malignant biliary obstruction. The angle between the target biliary duct stricture and the first implanted SEMS was significantly higher in the failure than in the success group. There were significantly fewer wire or dilation devices passing the first SEMS cell in the failure group than in the success group. The angle was significantly smaller in patients with wire or dilation devices passing the first SEMS cell. In conclusion, a large angle was identified as a predictive factor for failure of stent-in-stent SEMS placement.