Which scope is appropriate for endoscopic retrograde cholangiopancreatography after Billroth II reconstruction:An esophagogastroduodenoscope or a colonoscope?

BACKGROUND Recently,with the advent of more advanced devices and endoscopic techniques,endoscopic retrograde cholangiopancreatography(ERCP)in Billroth II(B-II)patients has been increasingly performed.However,the procedures are difficult,and the techniques and strategies have not been defined.AIM To reveal the appropriate scope for ERCP in B-II patients.METHODS Sixty ERCP procedures were performed on B-II patients between June 2005 and May 2018 at Fukushima Medical University Hospital,and in 44 cases,this was the first ERCP procedure performed by esophagogastroduodenoscopy(EGDS)or colonoscopy(CS)after B-II gastrectomy.These cases were divided into two groups:17 cases of ERCP performed by EGDS(EGDS group)and 27 cases of ERCP performed by CS(CS group).The patient characteristics and ERCP procedures were compared between the EGDS and CS groups.RESULTS The procedural time was significantly shorter in the EGDS group than in the CS group[median(range):60(20-100)vs 90(40-128)min,P value<0.01].CS was an independent factor of a longer ERCP procedural time according to the univariate and multivariate analyses(odds ratio:3.97,95%CI:1.05-15.0,P value=0.04).CONCLUSION Compared to CS,EGDS shortened the procedural time of ERCP in B-II patients.

Screening for hilar biliary invasion in ampullary cancer patients

BACKGROUND The treatment for ampullary cancer is pancreatoduodenectomy or local ampullectomy.However,effective methods for the preoperative investigation of hilar biliary invasion in ampullary cancer patients have not yet been identified.AIM To determine the necessity of and an appropriate method for investigating hilar biliary invasion of ampullary cancer.METHODS Among 43 ampullary cancer patients,34 underwent endoscopic treatment(n=9)or surgery(n=25).The use of imaging findings(thickening and enhancement of the bile duct wall on contrast-enhanced computed tomography,irregularity on endoscopic retrograde cholangiography,thickening of the entire bile duct wall on intraductal ultrasonography(IDUS),and partial thickening of the bile duct wall on IDUS)and biliary biopsy results for diagnosing hilar biliary invasion of ampullary cancer was compared.RESULTS Hilar invasion was not observed in every patient.Among the patients who did not undergo biliary stent insertion,the combination of partial thickening of the bile duct wall on IDUS and biliary biopsy results showed the highest accuracy(100%)for diagnosing hilar biliary invasion.However,each imaging method and biliary biopsy yielded some false-positive results.CONCLUSION Although some false-positive results were obtained with each method,the combination of partial thickening of the bile duct wall on IDUS and biliary biopsy results was useful for diagnosing hilar biliary invasion of ampullary cancer.However,hilar invasion of ampullary cancer is rare;therefore,the investigation of hilar biliary invasion of ampullary cancer might be unnecessary.

Present state of endoscopic ultrasonography-guided fine needle aspiration for the diagnosis of autoimmune pancreatitis type 1

Autoimmune pancreatitis(AIP)is defined as pancreatitis caused by irregular narrowing of the pancreatic duct accompanied by pancreatic swelling,fibrosis and lymphocyte infiltration,events that are related to autoimmune mechanisms.The 2010 International Consensus Diagnostic Criteria for AIP defined pancreatitis as“type 1”when increased levels of serum IgG4 were present and other organs were involved;lymphoplasmacytic sclerosing pancreatitis was the main histological characteristic.Apart from surgery,endoscopic ultrasonographyguided fine needle aspiration(EUS-FNA)is the only method for the histological diagnosis of AIP;however,this method is difficult.The use of larger-diameter FNA needles and trucut biopsy did not improve the diagnostic performance of EUS-FNA,but it has improved gradually.In this review,we look back at past efforts to improve the diagnostic performance of EUS-FNA and reveal the present state of EUS-FNA for the histological diagnosis of AIP type 1.

Can the wet suction technique change the efficacy of endoscopic ultrasound-guided fine-needle aspiration for diagnosing autoimmune pancreatitis type 1? A prospective single-arm study

BACKGROUND Other than surgery,endoscopic ultrasound-guided fine-needle aspiration(EUSFNA)is the only procedure for histologically diagnosing autoimmune pancreatitis(AIP).However,adequate specimens are difficult to obtain.Recently,more adequate specimens were reported to be obtained with EUS-FNA with a wet suction technique(WEST)than with conventional EUS-FNA.AIM To histologically diagnose AIP by EUS-FNA with a WEST.METHODS Eleven patients with possible type 1 AIP between February 2016 and August 2018 underwent EUS-FNA with a WEST(WEST group),with four punctures by 19 or 22 G needles.As a historical control,23 type 1 AIP patients who underwent no fewer than four punctures with 19 or 22 G needles were enrolled(DRY group).Patient characteristics and histological findings were compared between the two groups.RESULTS Three histopathological factors according to the International Consensus Diagnostic Criteria were significantly greater in the WEST group than the DRY group[lymphoplasmacytic infiltrate without granulocytic infiltration:9(81.8%)vs 6(26.1%),P=0.003,storiform fibrosis:5(45.5%)vs 1(4.3%),P=0.008,abundant(>10 cells/HPF)IgG4-positive cells:7(63.6%)vs 5(21.7%),P=0.026].Level 1 or level 2 histopathological findings were observed more often in the WEST group than in the DRY group[8(72.7%)vs 3(13.0%),P=0.001].CONCLUSION EUS-FNA with a WEST was more successful than standard EUS-FNA in histologically diagnosing AIP.

Pancreatic stents to prevent post-endoscopic retrograde cholangiopancreatography pancreatitis: A meta-analysis

BACKGROUND Endoscopic retrograde cholangiopancreatography(ERCP)plays a major role in the investigation and treatment of pancreaticobiliary diseases.However,post-ERCP pancreatitis(PEP)is a severe adverse effect.Prior meta-analyses have shown that prophylactic PS was useful for preventing PEP.However,abstract reports and patients who underwent endoscopic ampullectomy were included in the previous analyses.In addition,two meta-analyses involved non-randomized controlled trials(RCTs).The efficacy of PS for preventing severe PEP was different in each meta-analysis.Therefore,we performed the current metaanalysis,which included only full-text articles,and added new findings.AIM To reveal the efficacy of prophylactic pancreatic stent(PS)placement for preventing PEP.METHODS We searched the MEDLINE,Cochrane Library and PubMed databases for related RCTs.Among the reports retrieved,11 studies were included in this metaanalysis.All full-text articles were published between 1993 and 2016.A total of 1475 patients were enrolled in the included studies;of these patients,734 had a PS inserted,and 741 did not have a PS inserted.PEP and severe PEP occurrence were evaluated in this meta-analysis.RESULTS PEP was observed in all studies and occurred in 39(5.3%)patients who received a PS.On the other hand,PEP occurred in 141(19%)patients who did not receive a PS.The occurrence of PEP was significantly lower in the patients who underwent PS placement than in the patients who did not receive a PS(OR=0.32;95%CI:0.23-0.45;P<0.001).In addition,the occurrence of severe PEP was evaluated.Notably,the occurrence of severe PEP was not observed in the stent group;however,the occurrence of severe PEP was observed in 8(1.3%)patients who did not have a PS inserted.Severe PEP occurred significantly less often in the stent group than in the no stent group(OR=0.24;95%CI:0.06-0.94;P=0.04).CONCLUSION In conclusion,prophylactic PS placement is useful for preventing PEP and severe PEP.

Appropriate number of biliary biopsies and endoscopic retrograde cholangiopancreatography sessions for diagnosing biliary tract cancer

BACKGROUND Biliary ductal cancer(BDC) is a lethal disease; however, diagnosing BDC is challenging. Biliary biopsies are performed to pathologically diagnose BDC, but the appropriate parameters for biliary biopsy [number of biliary biopsies, number of endoscopic retrograde cholangiopancreatography(ERCP) sessions, etc.] are unknown.AIM To clarify what constitutes an adequate method for biliary biopsy.METHODS In total, 95 patients who underwent endoscopic biliary biopsy without choledochoscopy and who were pathologically diagnosed with BDC were enrolled in this study. The patients were divided into two groups. Seventy-six patients who were diagnosed by biliary biopsy were defined as the positive group(P group), and nineteen patients who were not diagnosed by biliary biopsy were defined as the negative group(N group). The patient characteristics and ERCP-related procedures were compared between the P and N groups.RESULTS The numbers of ERCP sessions and biliary biopsies were significantly different between the two groups [ERCP sessions(one/two), P group 72/4 vs N group15/4, P value = 0.048; number of biliary biopsies, P group 2(1-6) vs N group 2(1-7), P value = 0.039]. In a multivariate analysis, fewer than 2 ERCP sessions was an independent factor influencing the positivity of the biliary biopsies.CONCLUSION This study clarified that ERCP and biliary ductal biopsy should only be performed once. If biliary cancer is not pathologically diagnosed after the first ERCP session, other methods(Endoscopic ultrasonography-guided fine needle aspiration or choledochoscopy-guided biliary ductal biopsy) should be employed.

Push vs pull method for endoscopic ultrasound-guided fine needle aspiration of pancreatic head lesions: Propensity score matching analysis

AIM To evaluate the efficacy of endoscopic ultrasoundguided fine needle aspiration(EUS-FNA) of pancreatic head cancer when pushing(push method) or pulling the echoendoscope(pull method).METHODS Overall, 566 pancreatic cancer patients had their first EUS-FNA between February 2001 and December 2017. Among them, 201 who underwent EUS-FNA for pancreatic head lesions were included in this study. EUS-FNA was performed by the push method in 85 patients, the pull method in 101 patients and both the push and pull methods in 15 patients. After propensity score matching(age, sex, tumor diameter, and FNA needle), 85 patients each were stratified into the push and pull groups. Patient characteristics and EUSFNA-related factors were compared between the two groups.RESULTS Patient characteristics were not significantly different between the two groups. The distance to lesion was significantly longer in the push group than in the pull group(13.9 ± 4.9 mm vs 7.0 ± 4.9 mm, P < 0.01). The push method was a significant factor influencing the distance to lesion(≥ median 10 mm)(P < 0.01). Additionally, tumor diameter ≥ 25 mm(OR = 1.91, 95%CI: 1.02-3.58, P = 0.043) and the push method(OR = 1.91, 95%CI: 1.03-3.55, P = 0.04) were significant factors contributing to the histological diagnosis of malignancy.CONCLUSION The pull method shortened the distance between the endoscope and the lesion and facilitated EUS-FNA of pancreatic head cancer. The push method contributed to the histological diagnosis of pancreatic head cancer using EUS-FNA specimens.

Biliary metal stents should be placed near the hilar duct in distal malignant biliary stricture patients

BACKGROUND Endoscopic biliary drainage using a self-expandable metallic stent(SEMS)has been widely performed to treat distal malignant biliary obstruction(DMBO).However,the optimal position of the stent remains unclear.AIM To determine the ideal position for SEMS placement.METHODS In total,135 DMBO patients underwent SEMS(uncovered or covered)placement over a ten-year period.A total of 127 patients with biliary obstruction between the junction of the cystic duct and Vater’s papilla were enrolled.An SEMS was placed through the upper common bile duct 2 cm from the biliary hilar duct in 83 patients(Hilar group)or near the top of the biliary obstruction in 44 patients(Lower group).Technical and functional success,adverse events,and risk factors for SEMS dysfunction were evaluated.RESULTS The stent patency period was significantly longer in the Hilar group than in the Lower group(P value<0.01).In multivariate analysis,the only statistically significant risk factor for SEMS dysfunction was being in the Lower group(hazard ratio:9.94,95%confidence interval:2.25–44.0,P<0.01).CONCLUSION A longer patency period was achieved by positioning the SEMS near the biliary hilar duct.

Dysbiosis of the duodenal microbiota as a diagnostic marker for pancreaticobiliary cancer

BACKGROUND Pancreaticobiliary cancer(PB Ca)is a lethal disease,and a useful diagnostic marker is urgently needed.A correlation between the human microbiota and malignant gastrointestinal diseases was recently reported.AIM To investigate the efficacy of the duodenal microbiota for diagnosing PB Ca.METHODS We recruited 22 patients with benign pancreaticobiliary diseases(benign group)and 12 patients with PB Ca(malignant group).The duodenal microbiota of each patient was analyzed by the 16S rDNA terminal restriction fragment length polymorphism method.Patient characteristics,tumor markers,and relative abundances of the duodenal microbiota were compared between the benign and malignant groups.RESULTS Cancer antigen 19-9(CA19-9),Bifidobacterium,Clostridium cluster XVIII,and Prevotella levels differed significantly between the benign and malignant groups.Clostridium cluster XVIII had the greatest area under the receiver operating characteristic curve(AUC)among the four factors with respect to diagnosing PB Ca(cutoff value:3.038%;sensitivity:58.3%;specificity:95.2%;AUC:0.81).The combination of Clostridium cluster XVIII(cutoff value:3.038%)and CA19-9 Levels(cutoff value:18.8 U/mL)showed 91.7%sensitivity and 71.4%specificity for diagnosing PB Ca.CONCLUSION The duodenal microbiota may be useful for PB Ca screening.

Prevention of post-endoscopic retrograde cholangiopancreatography pancreatitis using pancreatic stents: A review of efficacy, diameter and length

Although endoscopic retrograde cholangiopancreatography (ERCP) is an important procedure for the diagnosis and treatment of pancreaticobiliary diseases, post-ERCP pancreatitis (PEP) is the most frequent adverse event that can sometimes be fatal. However, prophylactic pancreatic stent (PS) insertion has been performed to prevent PEP in high-risk patients. In some randomized controlled trials (RCTs) and meta-analyses, the efficacy of prophylactic PS insertion has been shown to prevent PEP. In addition, several types of stents have been used to decrease PEP. In this review, we introduce the details of these RCTs and meta-analyses and reveal the specifications for stent placement, for example, the stent diameter and length and the pancreatic region into which the stent should be inserted.