[Single-operator Cholangioscopy Guided Lithotripsy].

ERCP is the standard treatment for common bile duct stones (CBD stones). On the other hand, in approximately 10% of patients with CBD stones, the complete removal of the stones cannot be achieved by conventional ERCP, which performs endoscopic sphincterotomy followed by stone extraction. Additional advanced and complex procedures are often necessary to remove these "difficult bile duct stones", including endoscopic papillary large balloon dilatation or mechanical lithotripsy. Advances in cholangioscopy have made electrohydraulic or laser lithotripsy under direct endoscopic visualization possible during ERCP. Cholangioscopy-guided lithotripsy using the SpyGlass DS system could be a better treatment tool for removing difficult stones. The focus of this review was to describe single-operator cholangioscopy in the management of difficult CBD stones.

Predictors of stent dysfunction in patients with bilateral metal stents for malignant hilar obstruction.

INTRODUCTION: For unresectable hilar obstruction, restoring and maintaining biliary ductal patency are crucial for improved survival and quality of life. The endoscopic placement of stents is now a mainstay of its treatment, and bilateral stenting is effective for biliary decompression. This study aimed to determine the clinical outcomes of bilateral metal stent placement using large cell-type stents and the clinical predictors of stent dysfunction in patients with malignant hilar obstruction. METHODS: We performed a retrospective analysis of patients who underwent bilateral metal stent placement using two large cell-type stents at two academic teaching hospitals between September 2017 and February 2019. The primary outcome was stent dysfunction. Secondary outcomes included predictors related to stent dysfunction and overall survival. RESULTS: The study included 87 patients who underwent bilateral metal stent placement for malignant hilar obstruction. Technical success and clinical success were achieved in 80 patients (92.0%) and 83 patients (95.4%), respectively. During the follow-up period (median: 201, range: 18-671 days), stent dysfunction occurred in 42 patients (48.3%), and the median stent patency was 199 days (95% confidence interval [CI]: 181-262). In univariate analysis, age, cholangitis before stent insertion, and subsequent chemotherapy were found to be associated with the cumulative risk of stent dysfunction. In multivariate analysis, cholangitis before stent insertion (hazards ratio [HR]: 2.26, 95% CI: 1.216-4.209, P = 0.010) and subsequent chemotherapy (HR: 0.250, 95% CI: 0.130-0.482, P<0.001) remained as statically significant factors associated with the cumulative risk of stent dysfunction. The median overall survival was 288 days (95% CI: 230-327). CONCLUSION: The bilateral placement of large cell-type stents for malignant hilar obstruction was effective with high technical and clinical success rates and acceptable patency. Cholangitis before stent insertion was associated with shorter patency, and subsequent chemotherapy was associated with longer stent patency.

Recent advances in the management of difficult bile-duct stones: a focus on single-operator cholangioscopy-guided lithotripsy.

The most effective and the standard treatment for bile duct stones (BDSs) is endoscopic retrograde cholangiopancreatography (ERCP). However, in 10% to 15% of patients with BDSs, the stones cannot be removed by conventional ERCP, which involves endoscopic sphincterotomy followed by balloon or basket extraction. Additional techniques or devices are often necessary to remove these difficult bileduct stones, including endoscopic papillary large balloon dilatation to make a larger papillary opening and/or mechanical lithotripsy to fragment the stones. Advances in cholangioscopy have made possible electrohydraulic or laser lithotripsy under direct cholangioscopic visualization during ERCP. Cholangioscopy-guided lithotripsy could be another good option in the armamentarium of techniques for removing difficult BDSs. Here we review endoscopic techniques based on single-operator cholangioscopy for the management of difficult BDSs.

Progression to invasive cancer after snare polypectomy of intracholecystic papillary neoplasms during gallbladder stone removal by percutaneous transhepatic choledochoscopy: a case report.

BACKGROUND: Intracholecystic papillary neoplasms (ICPNs) of the gallbladder are rare, preinvasive lesions characterized by an intracholecystic papillary growth that may be associated with invasive adenocarcinoma. The natural history of ICPN is unknown. Here, we report a case of ICPN, highlighting its natural course. CASE PRESENTATION: A 79-year-old woman presented to the emergency department with perforated cholecystitis. After percutaneous transhepatic gallbladder drainage, due to the presence of surgical risk factors, we opted to perform gallstone removal through percutaneous transhepatic cholangioscopy instead of cholecystectomy. ICPN, which was accidentally detected after the removal of the gallbladder stones, was also endoscopically removed. After 4 years, the patient came back to the hospital with a large gallbladder mass. After cholecystectomy, pathological examination revealed ICPN with invasive adenocarcinoma. CONCLUSION: The current case showed endoscopic findings of ICPN and its natural progression, particularly its clinicopathological features and outcomes.

Radiation exposure during endoscopic retrograde cholangiopancreatography according to clinical determinants.

This study aimed to analyze the dose of radiation to which the physician is exposed during endoscopic retrograde cholangiopancreatography (ERCP) and to identify predictive factors of radiation exposure during the procedure. Furthermore, we evaluated the patient characteristics and procedural factors associated with prolonged fluoroscopy time (FT).A cross-sectional retrospective analysis of 780 ERCPs performed at a tertiary academic hospital over a 2-year period was conducted. The primary outcome was radiation exposure during ERCP as determined by FT; additionally, the association between variables and radiation exposure was determined. Moreover, we evaluated their correlations with age, sex, body mass index (BMI), diagnosis, duration of procedure, procedure name, and procedure complexity.According to the analysis of the 780 ERCPs performed in 2 years, the mean FT was 5.07 minutes (95% confidence interval [CI], 4.87-5.26). The mean radiation durations were as follows: cholelithiasis, 5.76 minutes (95% CI, 4.75-6.80); malignant biliary obstruction, 6.13 minutes (95% CI, 5.91-6.35); pancreatic disease, 5.28 minutes (95% CI, 4.45-6.28); and benign biliary stricture, 5.32 minutes (95% CI, 5.02-5.94). Significant differences affecting fluoroscopy duration between the 2 endoscopists were not observed in the present study. Multivariate analysis revealed that prolonged fluoroscopy duration was related to specific characteristics, including higher BMI (BMI >27.5 kg/m) (+4.1 minutes; 95% CI, 2.56-5.63), mechanical lithotripsy (+4.85 minutes; 95% CI, 0.45-9.25), needle-knife use (+4.5 minutes; 95% CI, 2.15-6.86), and malignant biliary obstruction (+2.34 minutes; 95% CI, 0.15-4.53).ERCPs are associated with significantly higher radiation exposure of patients on the specific procedure. Endoscopists should be aware of the determining factors, including patients with obesity, who underwent mechanical lithotripsy, who had malignant biliary obstruction, and who underwent a procedure using a needle knife, that affect FT during ERCP.

Predictors of Malignancy in "Pure" Branch-Duct Intraductal Papillary Mucinous Neoplasm of the Pancreas without Enhancing Mural Nodules on CT Imaging: A Nationwide Multicenter Study.

Background/Aims: Presence of enhanced mural nodules, which can be visualized using computed tomography (CT), is one of high-risk stigmata in branch-duct intraductal papillary mucinous neoplasms (BD-IPMNs). Conversely, the absence of enhanced mural nodules on preoperative imaging does not exclude malignant risk. The present study aimed to investigate other morphological features as predictors of malignancy in "pure" BD-IPMNs without enhanced mural nodules on CT. Methods: This retrospective study included 180 patients with surgically confirmed "pure" BD-IPMNs of the pancreas and no enhanced mural nodules on preoperative CT. The study was conducted at 15 tertiary referral centers throughout South Korea. Univariate and multivariate analyses were used to identify significant predictors of malignancy. Results: BD-IPMNs with low-grade (n=84) or moderate-grade (n=76) dysplasia were classified as benign; those with high-grade dysplasia (n=8) or invasive carcinoma (n=12) were classified as malignant. The multivariate analysis revealed that cyst size ≥30 mm (odds ratio, 8.6; p=0.001) and main pancreatic duct diameter ≥5 mm (odds ratio, 4.1; p=0.01) were independent risk factors for malignancy in "pure" BD-IPMNs without enhanced mural nodules on CT. Endoscopic ultrasound detected enhanced mural nodules (6/82) that had been missed on CT, and two IPMNs with enhanced mural nodules were malignant. Conclusions: In patients with "pure" BD-IPMNs who have no enhanced mural nodules on CT, cyst size ≥30 mm and main pancreatic duct diameter ≥5 mm may be associated with malignancy.

Combination of Helicobacter pylori infection and the interleukin 8 -251 T > A polymorphism, but not the mannose-binding lectin 2 codon 54 G > A polymorphism, might be a risk factor of gastric cancer.

BACKGROUND: Mannose-binding lectin (MBL) acts in the innate immune response to Helicobacter pylori. Interleukin 8 (IL-8) is a potent cytokine produced by gastric epithelial cells in response to H. pylori. We aimed to investigate whether polymorphisms in MBL2 and IL-8 influence susceptibility to H. pylori infection, and the associations of these polymorphisms with the risk of gastroduodenal diseases in a Korean population. METHODS: We consecutively enrolled 176 H. pylori-negative control subjects, 221 subjects with H. pylori-positive non-atrophic gastritis, 52 mild atrophic gastritis (AG), 61 severe AG, 175 duodenal ulcer, and 283 gastric cancer (GC). Allele-specific PCR-RFLP was conducted for polymorphisms in MBL2 exon 1 (codon 52, 54, and 57) and IL-8 -251 T > A. IL-8 levels in gastric mucosal tissues and serum MBL levels were measured by enzyme-linked immunosorbent assay. RESULTS: MBL2 exon 1 polymorphic variants were found only in codon 54, and the allele frequencies did not differ significantly between the control and disease groups. Although serum MBL levels in codon 54 A/A mutants were markedly low, it did not influence susceptibility to H. pylori infection or the risk of gastroduodenal diseases. IL-8 levels were significantly different between T/T wild type, T/A heterozygote, and A/A mutant genotypes. IL-8 -251 A allele carriers (A/A + T/A) showed increased IL-8 levels, and were significantly associated with the risk of severe AG and GC. CONCLUSIONS: We suggest that a combination of H. pylori infection and the IL-8 -251 T > A polymorphism might increase the risk of severe AG and GC in a Korean population.

A Double-Layered Covered Biliary Metal Stent for the Management of Unresectable Malignant Biliary Obstruction: A Multicenter Feasibility Study.

BACKGROUND/AIMS: The covered self-expandable metal stent (CMS) was developed to prevent tumor ingrowth-induced stent occlusion during the treatment of malignant biliary obstruction. However, complications such as cholecystitis, pancreatitis, and stent migration can occur after the endoscopic insertion of CMSs. The aim of the present study was to assess the efficacy and safety of a double-layered CMS (DCMS) for the management of malignant bile duct obstruction. METHODS: DCMSs were endoscopically introduced into 59 patients with unresectable malignant extrahepatic biliary obstruction at four tertiary referral centers, and the patient medical records were retrospectively reviewed. RESULTS: Both the technical and functional success rates were 100%. Procedure-related complications including pancreatitis, cholangitis, stent migration, and liver abscess occurred in five patients (8.5%). The median follow-up period was 265 days (range, 31 to 752 days). Cumulative stent patency rates were 68.2% and 40.8% at 6 and 12 months, respectively. At the final follow-up, the rate of stent occlusion was 33.9% (20/59), and the median stent patency period was 276 days (range, 2 to 706 days). CONCLUSIONS: The clinical outcomes of DCMSs were comparable to the outcomes previously reported for CMSs with respect to stent patency period and complication rates.

Room for Quality Improvement in Endoscopist-Directed Sedation: Results from the First Nationwide Survey in Korea.

BACKGROUND/AIMS: This study sought to characterize the current sedation practices of Korean endoscopists in real-world settings. METHODS: All active members of the Korean Society of Gastrointestinal Endoscopy were invited to complete an anonymous 35-item questionnaire. RESULTS: The overall response rate was 22.7% (1,332/5,860). Propofol-based sedation was the dominant method used in both elective esophagogastroduodenoscopy (55.6%) and colonoscopy (52.6%). The mean satisfaction score for propofol-based sedation was significantly higher than that for standard sedation in both examinations (all p<0.001). The use of propofol was supervised exclusively by endoscopists (98.6%). Endoscopists practicing in nonacademic settings, gastroenterologists, or endoscopists with. CONCLUSIONS: Endoscopist-directed propofol administration is the predominant sedation method used in Korea. This survey strongly suggests that there is much room for quality improvement regarding sedation training and patient vigilance in endoscopist-directed sedation.

[Recent Advances in the Management of Recurrent Bile Duct Stones].

Approximately 3-15% of patients who have undergone removal of bile duct stones with endoscopic sphincterotomy have recurrence of stones which often presents as acute cholangitis. Despite better understanding on the factors and mechanisms underlying the recurrence of bile duct stones achieved during the past few decades, endoscopic removal still remains the mainstay of management for recurrent bile duct stones. Recently investigated and suggested management of recurrent bile duct stones are highlighted in this review.

Polymorphisms in PRKCDBP, a Transcriptional Target of TNF-α, Are Associated With Inflammatory Bowel Disease in Korean.

BACKGROUND/AIMS: Emerging data indicate that polymorphic sequence variations in the tumor necrosis factor alpha (TNF-α) gene may affect its production, and be associated with the risk of inflammatory bowel disease (IBD). PRKCDBP is a putative tumor suppressor gene and a transcriptional target of TNF-α. The aim of this case-control study is to explore the possible association of single nucleotide polymorphisms (SNPs) in PRKCDBP with the development of IBD in Koreans. METHODS: Genotyping analysis of four SNPs of PRKCDBP [rs35301211 (G210A), rs11544766 (G237C), rs12294600 (C797T), and rs1051992 (T507C)] was performed on 170 ulcerative colitis (UC),131 Crohn's disease (CD) patients, and 100 unrelated healthy controls using polymerase chain reaction and restriction fragment length polymorphism. RESULTS: Heterozygous configuration of three SNPs (G210A, G237C, and C797T) was very rare in both patients and healthy controls. However, allele frequencies of the T507C SNP showed a significant difference between UC patients and controls (P=0.037). The CC genotype of the T507C SNP was identified in 46.6% (61 of 131) of CD and 49.4% (84 of 170) of UC patients, but only in 33.0% (33 of 100) of healthy controls. Furthermore, CC homozygosity was more prevalent than TC heterozygosity in both CD and UC patients versus controls (P=0.016; gender-adjusted odds ratio [aOR], 2.16; 95% confidence interval [CI], 1.16-4.04 and P=0.009; aOR, 2.09; 95% CI, 1.193.64; respectively). CONCLUSIONS: Our results suggest that the T507C SNP in PRKCDBP, a TNF-α-inducible gene, might be associated with susceptibility to IBD (particularly UC) development in Koreans.

Efficacy of Magnesium Trihydrate of Ursodeoxycholic Acid and Chenodeoxycholic Acid for Gallstone Dissolution: A Prospective Multicenter Trial.

BACKGROUND/AIMS: Cholecystectomy is necessary for the treatment of symptomatic or complicated gallbladder (GB) stones, but oral litholysis with bile acids is an attractive alternative therapeutic option for asymptomatic or mildly symptomatic patients. This study was conducted to evaluate the efficacy of magnesium trihydrate of ursodeoxycholic acid (UDCA) and chenodeoxycholic acid (CDCA) on gallstone dissolution and to investigate improvements in gallstone-related symptoms. METHODS: A prospective, multicenter, phase 4 clinical study to determine the efficacy of orally administered magnesium trihydrate of UDCA and CDCA was performed from January 2011 to June 2013. The inclusion criteria were GB stone diameter ≤15 mm, GB ejection fraction ≥50%, radiolucency on plain X-ray, and asymptomatic/mildly symptomatic patients. The patients were prescribed one capsule of magnesium trihydrate of UDCA and CDCA at breakfast and two capsules at bedtime for 6 months. The dissolution rate, response rate, and change in symptom score were evaluated. RESULTS: A total of 237 subjects were enrolled, and 195 subjects completed the treatment. The dissolution rate was 45.1% and the response rate was 47.2% (92/195) after 6 months of administration of magnesium trihydrate of UDCA and CDCA. Only the stone diameter was significantly associated with the response rate. Both the symptom score and the number of patients with symptoms significantly decreased regardless of stone dissolution. Adverse events necessitating discontinuation of the drug, surgery, or endoscopic management occurred in 2.5% (6/237) of patients. CONCLUSIONS: Magnesium trihydrate of UDCA and CDCA is a well-tolerated bile acid that showed similar efficacy for gallstone dissolution and improvement of gallstone-related symptoms as that shown in previous studies.

Predictors of malignancy in pure branch duct type intraductal papillary mucinous neoplasm of the pancreas: A nationwide multicenter study.

BACKGROUND/OBJECTIVES: Prediction of malignancy in patients with BD-IPMNs is critical for the management. The aim of this study was to elucidate predictors of malignancy in patients with 'pure' BD-IPMNs who had a main pancreatic duct (MPD) diameter of ≤5 mm according to the most recent international consensus criteria and in whom MPD involvement was excluded on postoperative histology. METHODS: We identified 177 patients with 'pure' BD-IPMNs based on preoperative imaging and postoperative histology from 15 tertiary referral centers in Korea. BD-IPMNs with low-grade (n = 72) and moderate-grade (n = 66) dysplasia were grouped as benign and BD-IPMNs with high-grade dysplasia (n = 10) and invasive carcinoma (n = 29) were grouped as malignancy. RESULTS: On univariate analysis, particular symptoms (jaundice and clinical pancreatitis), CT findings (cyst size > 3 cm, the presence of enhancing mural nodules) and EUS features (the presence of mural nodules, the mural nodule size > 5 mm) were significant risk factors predicting malignant BD-IPMNs. Multivariate analysis revealed that the cyst size > 3 cm (odds ratio = 9.9), the presence of enhancing mural nodules on CT (odds ratio = 19.3) and the mural nodule size > 5 mm on EUS (odds ratio = 14.9) were the independent risk factors for the presence of malignancy in BD-IPMNs (p < 0.001). CONCLUSIONS: The cyst size > 3 cm, the presence of enhancing mural nodules on CT, the mural nodule size > 5 mm on EUS are three independent predictors of malignancy in patients with 'pure' BD-IPMNs.

Highlights from the 50th seminar of the korean society of gastrointestinal endoscopy.

The July issue of Clinical Endoscopy deals with selected articles covering the state-of-the-art lectures delivered during the 50th seminar of the Korean Society of Gastrointestinal Endoscopy (KSGE) on March 30, 2014, highlighting educational contents pertaining to either diagnostic or therapeutic gastrointestinal (GI) endoscopy, which contain fundamental and essential points in GI endoscopy. KSGE is very proud of its seminar, which has been presented twice a year for the last 25 years, and hosted more than 3,500 participants at the current meeting. KSGE seminar is positioned as one of premier state-of-the-art seminars for endoscopy, covering topics for novice endoscopists and advanced experts, as well as diagnostic and therapeutic endoscopy. The 50th KSGE seminar consists of more than 20 sessions, including a single special lecture, concurrent sessions for GI endoscopy nurses, and sessions exploring new technologies. Nine articles were selected from these prestigious lectures, and invited for publication in this special issue. This introductory review, prepared by the editors of Clinical Endoscopy, highlights core contents divided into four sessions: upper GI tract, lower GI tract, pancreatobiliary system, and other specialized topic sessions, including live demonstrations and hands-on courses.

A case of early gastric cancer with solitary metastasis to the pleura.

The incidence of early gastric cancer (EGC) has increased to >50% in Korea owing to a higher detection rate caused by rapid advances in diagnostic instrumentation. EGC with distant metastasis has been rarely reported. Here, we report the case of a 76-year-old woman in whom general EGC was initially diagnosed by endoscopy and endoscopic ultrasonography. She subsequently underwent endoscopic submucosal dissection (ESD). Histological examination of the ESD specimen revealed that neoplastic cells were located predominantly in the submucosal layer and submucosal lymphatic channels. Metastatic cancer cells were also found in the pleural effusion. After conducting all analyses, including immunohistochemical staining, we concluded that the patient had primary EGC with pleural metastasis.

Highlights of international digestive endoscopy network 2013.

Rapid advances in the technology of gastrointestinal endoscopy as well as the evolution of science have made it necessary for us to continue update in either various endoscopic techniques or state of art lectures relevant to endoscopy. International Digestive Endoscopy Network (IDEN) 2013 was held in conjunction with Korea-Japan Joint Symposium on Gastrointestinal Endoscopy (KJSGE) during June 8 to 9, 2013 at Seoul, Korea. Two days of impressive scientific program dealt with a wide variety of basic concerns from upper gastrointestine (GI), lower GI, pancreaticobiliary endoscopy to advanced knowledge including endoscopic submucosal dissection forum. IDEN seems to be an excellent opportunity to exchange advanced information of the latest issues on endoscopy with experts from around the world. In this special issue of Clinical Endoscopy, we prepared state of art review articles from contributing authors and the current highlights will skillfully deal with very hot spots of each KJSGE, upper GI, lower GI, and pancreaticobiliary sessions by associated editors of Clinical Endoscopy.

Highlights of the 48th seminar of korean society of gastrointestinal endoscopy.

This special May issue of Clinical Endoscopy discusses the tutorial contents dealing with either the diagnostic or therapeutic gastrointestinal (GI) endoscopy that contain very fundamental and essential points in this filed. The seminar of Korean Society of Gastrointestinal Endoscopy (KSGE) had positioned as one of prime educational seminars covering the very beginner to advanced experts of GI endoscopy. Besides of four rooms allocated for each lecture, two additional rooms were open for either live demonstration or hands-on course, covering totally 20 sessions including one special lecture. Among these prestigious lectures, 12 lectures were selected for the current review articles in this special issue of Clinical Endoscopy journal. Basic course for beginner to advanced tips to expert were all covered in this seminar. This introductory review prepared by four associated editors of Clinical Endoscopy contained core contents divided into four sessions-upper gut, lower gut, pancreaticobiliary, and specialized topic session part-to enhance understandings not covered by enlisted review articles in this issue.