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TOKYO criteria: Standardized reporting system for endoscopic biliary stent placement

Tsuyoshi Hamada, Yousuke Nakai, and Hiroyuki Isayama

Abstract : Placement of a plastic or metal stent via endoscopic retrograde cholangiopancreatography (ERCP) currently serves as the first-line procedure for obstructive jaundice and acute cholangitis. Dysfunction of the biliary stent causes recurrence of symptoms and often requires reinterventions and hospitalizations. Therefore, duration of stent patency is commonly used as the primary endpoint in clinical studies of biliary stents. However, owing to considerable heterogeneity between studies in reporting of biliary stent patency, it has been difficult to compare and integrate results of independent studies. There has been between-study heterogeneity in definitions of stent patency, statistics reported for survival curves of stent patency, and methods to treat censored cases. In addition to stent occlusion, stent migration is a major cause of recurrent biliary obstruction after covered metal stent placement, which further complicates the reporting of stent patency. Reporting of functional success and adverse events has been also inconsistent between the studies. From the perspective of evidence-based medicine, the variations in the definitions of outcome variables potentially hinder robust meta-analyses. To overcome the issues due to the lack of outcome reporting guidelines on the topic, the TOKYO criteria 2014 for reporting outcomes associated with endoscopic transpapillary placement of biliary stents have been proposed. Due to their comprehensiveness, the TOKYO criteria can be readily utilized to evaluate various types of biliary stent placement using ERCP, irrespective of types of stents and location of biliary stricture. In this article, we review the TOKYO criteria as a standardized reporting system for endoscopically-placed biliary stents. We also discuss potential controversial issues in the application of the TOKYO criteria. Given that endoscopic ultrasound-guided biliary drainage is increasingly utilized for cases with failed ERCP or altered gastrointestinal anatomy, we further propose a potential application of the TOKYO criteria to reporting of outcomes of this procedure.

Usefulness of stent placement above the papilla, so-called, ‘inside stent’

Tanyaporn Chantarojanasiri , Hirofumi Kogure, Tsuyoshi Hamada, Yousuke Nakai, and Hiroyuki Isayama

Abstract : Stent occlusion and cholangitis are common complications after endoscopic biliary stenting caused by duodenobiliary refluxes and food impaction. To prolong the stent patency, the concept of stenting above the papilla, so-called inside stent, has been developed. Various studies of the inside stent in the treatment of both benign and malignant biliary obstruction have been published, with a promising result. However, most studies were retrospective, with wide variation of stent type and the etiology of biliary obstruction. This review aims to summarize the principle, evidence, and the usefulness of inside biliary stent.

Anastomotic stricture after liver transplantation: It is not Achilles’ heel anymore!

Sung Ill Jang, and Dong Ki Lee

Abstract : Biliary-tract complications, such as biliary strictures, anastomotic leaks, choledocholithiasis, and biliary casts, can occur after liver transplantation (LT). Of these complications, biliary strictures are regarded as an Achilles’ heel. Recently, treatment of anastomotic biliary stricture (ABS) has transitioned from conventional surgical revision to a nonsurgical treatment modality. Endoscopic serial balloon dilatation and/or multiple plastic stent replacements are highly effective and are now regarded as the first-line treatments. However, if the patient has undergone anastomosis by means of a hepaticojejunostomy, percutaneous treatment is performed. With recent technological advances and the rendezvous method, the clinical success rates of endoscopic and percutaneous ABS treatments have increased, but these methods fail in some patients who have total obstruction of anastomotic stricture. For these patients, magnetic compression anastomosis (MCA) has been suggested as an alternative method. Animal and human studies have demonstrated the safety and efficacy of MCA, and advancements in these nonsurgical methods have increased the clinical success rate of ABS. This review focuses on ABSs that develop after LT and discusses the clinical results of various nonsurgical methods and future directions.

Preoperative biliary drainage for pancreatic cancer

Osman Ahmed, and Jeffrey H. Lee

Abstract : Pancreatic cancer is a leading cause of cancer-related morbidity and mortality, but any meaningful improvement in its prognosis remains elusive. The lack of early diagnostic methods means that many patients only present when symptoms develop, such as obstructive jaundice. Once a diagnosis of pancreatic cancer has been made in a patient with obstructive jaundice, then a decision should be made if the patient is a candidate for surgical resection. Patients who are candidates for surgical resection generally do not need preoperative biliary drainage, unless they present with cholangitis, or if they require neo-adjuvant chemotherapy. If preoperative biliary drainage is to be done, then patient factors and local expertise should guide appropriate interventions. The evidence for endoscopic retrograde cholangiopancreatography as a first-line therapy for biliary decompression is strong; However, the use of percutaneous transhepatic biliary drainage as well as endoscopic ultrasound-guided biliary drainage has generally not been found to be inferior. Finally, to ensure ongoing patency and minimize complications, an appropriate self-expanding metal stent should ideally be placed.

Surgical management of the cases with both biliary and duodenal obstruction

Yoshihiro Miyasaka, Takao Ohtsuka, Vittoria Vanessa Velasquez, Yasuhisa Mori, Kohei Nakata, and Masafumi Nakamura

Abstract : Endoscopic management is presently the recommended first-line of treatment for biliary strictures. However, surgery still has an important role especially for biliary obstruction (BO) with duodenal obstruction. Even though endoscopic treatment for concurrent BO and gastric-outlet obstruction has been proposed, it is still not widespread. Duodenal obstruction is often associated with malignant BO which makes endoscopic treatment more challenging. Biliary and gastrointestinal double bypass with Roux-en-Y hepaticojejunostomy and gastrojejunostomy is the most common surgical intervention for malignant biliary and gastric-outlet obstruction. A variety of procedures of biliary bypass and gastrointestinal bypass have been reported. According to several studies, mortality rates range from 0% to 7%, while morbidity rates range from 3% to 50%. Higher morbidity was observed in symptomatic patients caused by the disease. Most common morbidity after double bypass was delayed gastric emptying. Recurrence of BO and gastric-outlet obstruction was less frequently seen after surgical bypass compared to after endoscopic treatment. Minimally invasive approach has been applied to double bypass. Studies showed that laparoscopic double bypass has a shorter hospital stay and reduced postoperative pain; however, due to its technical demand, it is still presently an uncommon procedure. Robotic bypass surgery may resolve this issue in the future. Further analyses of outcomes of both surgical and endoscopic treatments are necessary to establish better and suitable palliation options for concurrent biliary and duodenal obstruction caused by unresectable malignant tumors.

Which is better for unresectable malignant hilar biliary obstruction: Side-by-side versus stent-in-stent?

Itaru Naitoh , Tadahisa Inoue, and Kazuki Hayashi

Abstract : Biliary drainage is required for the management of unresectable malignant hilar biliary obstruction (UMHBO), and endoscopic transpapillary drainage is the first-line therapy because it is less invasive. Self-expandable metallic stents (SEMSs) are superior to plastic stents because they have longer stent patency and are more cost-effective. Endoscopic bilateral SEMS placement is technically challenging compared to unilateral placement. However, recent developments in devices and techniques have facilitated bilateral SEMS placement. There are two methods for bilateral hilar SEMS placement for UMHBO: side-by-side (SBS) and stent-in-stent (SIS). Sequential SBS was commonly conducted for bilateral hilar SEMS placement. In a new and thinner delivery system that was developed for SEM placement, two SEMSs could be simultaneously inserted and deployed through the working channel. This new bilateral stenting method enabled us to accomplish simultaneous SBS placement, which increased the success rate of SBS. Insertion of the guidewire and delivery of the second SEMS through the mesh of the first SEMS is challenging in SIS. Newly designed or modified SEMSs that are suitable for SIS have been developed to overcome this challenge, and these SEMSs have facilitated SIS. Uncovered SEMS has been commonly used for hilar SEMS placement, but covered SEMS (CSEMS) is another option for hilar SEMS placement, because CSEMS prevents tumor ingrowth and allows for removal of the stent for re-intervention. Therefore, CSEMS can be used for bilateral SEMS placement in SBS. There are many methods and kinds of SEMS available for bilateral SEMS placement. However, due to lack of evidence, there is no consensus on whether SBS or SIS is optimal for bilateral hilar SEMS placement. In this review, we compared various outcomes between SBS and SIS from previous studies, to clarify which method is better for bilateral SEMS placement for UMHBO.

Percutaneous placement of self-expandable metallic stents in patients with obstructive jaundice due to hepatocellular carcinoma

Hyun Pyo Hong , and Kyungmin Park

Abstract : “Icteric type hepatoma” is a hepatocellular carcinoma (HCC) with tumor invasion to the bile duct (bile duct tumor thrombus, BDTT) causing obstructive jaundice. Effective and long-term decompression of the bile duct is essential for the palliative treatment for the patients. Percutaneous self-expandable metallic stent placement is a well-established treatment for palliating patients with an inoperative malignant biliary obstruction. This article reviews the treatment of percutaneous placement of self-expandable metallic stents for the management of obstructive jaundice caused by HCC.

The vanishing stent: Repeated fracture and dissolution of nitinol gastric stents in a long term cancer survivor

Abstract : Nitinol self expandable metal stents are increasingly utilised for malignant obstruction in the proximal gastrointestinal tract. We describe a case in which repeated fracture of proximal duodenal stents with dissolution of the nitinol wire skeleton and covering membranes occurred in a long term cancer survivor. This necessitated placement of 4 stents for symptom control and to allow oral feeding until the patient’s death 20 months after the initial stent was inserted. Fracture of gastric and duodenal stents has rarely been described previously, some incidences of which were considered due to mechanical causes. Dissolution of stent metal skeletons has not previously been recognised in gastroduodenal stents but has been described in an oesophageal stent subject to reflux of gastric content and a biochemical mechanism has been proposed. With modern oncological treatment the prospect of patients outliving their stents is increasing and the need for repeat procedures should form part of the consent process.

Lipiodol brain embolism through right inferior phrenic artery-pulmonary vein shunt after transcatheter arterial chemoembolization

Eun Ho Jang, Eung Tae Kim, Woo Sun Choi, and Dong Il Gwon

Abstract : Lipiodol brain embolism is a rare complication associated with transcatheter arterial cheomoembolization (TACE). The present case describes a patient with lipiodol brain embolism who presented with several symptoms, including drowsy mental state, right facial palsy, and weakness in the right upper and lower limbs. The patient’s non-enhanced computed tomography scan and magnetic resonance imaging (MRI) findings revealed multifocal lipiodol deposition and an acute infarction of the brain. A retrospective review of the angiography findings revealed a right inferior phrenic artery-pulmonary vein shunt, which was not observed during the previous TACE. Three days after TACE, the patient’s symptoms improved; however, the extent of the brain hyperintensity had widened further on the following MRI. The patient gradually recovered and was finally discharged.