Still elusive: Developments in the accurate diagnosis of indeterminate biliary strictures

Indeterminate biliary strictures pose a significant diagnostic dilemma for gastroenterologists.Despite advances in endoscopic techniques and instruments,it is difficult to differentiate between benign and malignant pathology.A positive histological diagnosis is always preferred prior to high risk hepatobiliary surgery,or to inform other types of therapy.Endoscopic retrograde cholangiopancreato-graphy with brushings has low sensitivity and despite significant improvements in instruments there is still an unacceptably high false negative rate.Other methods such as endoscopic ultrasound and cholangioscopy have improved diagnostic quality.In this review we explore the techniques available to aid accurate diagnosis of indeterminate biliary strictures and obtain accurate histology to facilitate clinical management.

Diagnosis and Management of Biliary Strictures after Deceased-Donor Liver Transplantation Based on Clinical Practice

Biliary complications are still the main complications for liver transplantation recipients. Biliary strictures comprise the major part of all biliary complications after deceased-donor liver transplantation (LT). Biliary strictures following LT are divided into anastomotic strictures (AS) and non-anastomotic strictures (NAS). A Limitation of current published researches is that most studies aren’t based on clinical practice. The aim of this review is to summarize risk factors, clinical presentation, diagnosis and management in post-LT biliary strictures.

Focal intrahepatic strictures:A proposal classification based on diagnosis-treatment experience and systemic review

BACKGROUND Focal intrahepatic strictures(FIHS)refer to local strictures of the small and medium intrahepatic bile ducts.FIHS are easily misdiagnosed due to their rare incidence,and few studies have focused on the diagnosis and treatment approaches.AIM To propose a new classification for FIHS in order to guide its diagnosis and treatment.METHODS The symptoms,biochemistry results,imaging results,endoscopic examination results and initial and final diagnoses of 6 patients with FIHS admitted between January 2010 and December 2019 were retrospectively analyzed.RESULTS The 6 patients were diagnosed with intratubular growth-type intrahepatic cholangiocarcinoma(IG-ICC),recurrent multiple hepatocellular carcinoma(rmHCC)with bile duct tumor thrombus(BDTT),adenosquamous carcinoma(ASC),hepatolithiasis,small duct primary sclerosing cholangitis(SD-PSC)and autoimmune hepatitis(AIH).The initial and final diagnoses were not consistent in 4 patients.Hepatectomy was performed in patients with IG-ICC,ASC and hepatolithiasis according to the locations of their FIHS.Patients with rmHCC with BDTT received lenvatinib/sintilimab,while patients with SD-PSC and AIH received UDCA.We proposed the following classification system for FIHS:type I:FIHS located within one segment of the liver;type II:FIHS located at the confluence of the bile ducts of one segment or two adjacent segments;type III:FIHS connected to the left or right hepatic duct;and type IV:Multiple FIHS located in both lobes of the liver.CONCLUSION Our proposed classification system might help to guide the diagnosis and treatment of FIHS.Hepatectomy should be performed not only for malignant FIHS but also for benign strictures with severe secondary damage that cannot be improved by nonsurgical methods.

Current diagnosis and treatment of benign biliary stricturesafter living donor liver transplantation

Despite advances in surgical techniques, benign biliary strictures after living donor liver transplantation(LDLT) remain a significant biliary complication and play an important role in graft and patient survival. Benign biliary strictures after transplantation are classified into anastomotic or non-anastomotic strictures. These two types differ in presentation, outcome, and response to therapy. The leading causes of biliary strictures include impaired blood supply, technical errors during surgery, and biliary anomalies. Because patients usually have non-specific symptoms, a high index of suspicion should be maintained. Magnetic resonance cholangiography has gained widespread acceptance as a reliable noninvasive tool for detecting biliary complications. Endoscopy has played an increasingly prominent role in the diagnosis and treatment of biliary strictures after LDLT. Endoscopic management in LDLT recipients may be more challenging than in deceased donor liver transplantation patients because of the complex nature of the duct-to-duct reconstruction. Repeated aggressive endoscopic treatment with dilation and the placement of multiple plastic stents is considered the first-line treatment for biliary strictures. Percutaneous and surgical treatments are now reserved for patients for whom endoscopic management fails and for those with multiple, inaccessible intrahepatic strictures or Roux-en-Y anastomoses. Recent advances in enteroscopy enable treatment, even in these latter cases. Direct cholangioscopy, another advanced form of endoscopy, allows direct visualization of the inner wall of the biliary tree and is expected to facilitate stenting or stone extraction. Rendezvous techniques can be a good option when the endoscopic approach to the biliary stricture is unfeasible. These developments have resulted in almost all patients being managed by the endoscopic approach.

Biliary strictures complicating living donor liver transplantation:Problems,novel insights and solutions

Biliary stricture complicating living donor liver transplantation(LDLT) is a relatively common complication, occurring in most transplant centres across the world. Cases of biliary strictures are more common in LDLT than in deceased donor liver transplantation. Endoscopic management is the mainstay for biliary strictures complicating LDLT and includes endoscopic retrograde cholangiography, sphincterotomy and stent placement(with or without balloon dilatation). The efficacy and safety profiles as well as outcomes of endoscopic management of biliary strictures complicating LDLT is an area that needs to be viewed in isolation, owing to its unique set of problems and attending complications; as such, it merits a tailored approach, which is yet to be well established. The diagnostic criteria applied to these strictures are not uniform and are over-reliant on imaging studies showing an anastomotic narrowing. It has to be kept in mind that in the setting of LDLT, a subjective anastomotic narrowing is present in most cases due to a mismatch in ductal diameters. However, whether this narrowing results in a functionally significant narrowing is a question that needs further study. In addition, wide variation in the endotherapy protocols practised in most centres makes it difficult to interpret the results and hampers our understanding of this topic. The outcome definition for endotherapy is also heterogenous and needs to be standardised to allow for comparison of data in this regard and establish a clinical practice guideline. There have been multiple studies in this area in the last 2 years, with novel findings that have provided solutions to some of these issues. This review endeavours to incorporate these new findings into the wider understanding of endotherapy for biliary strictures complicating LDLT, with specific emphasis on diagnosis of strictures in the LDLT setting, endotherapy protocols and outcome definitions. An attempt is made to present the best management options currently available as well as directions for future research in the area.

Biliary drainage strategy of unresectable malignant hilar strictures by computed tomography volumetry

AIM:To identify criteria for predicting successful drainage of unresectable malignant hilar biliary strictures(UMHBS) because no ideal strategy currently exists.METHODS:We examined 78 patients with UMHBS who underwent biliary drainage.Drainage was considered effective when the serum bilirubin level decreased by ≥ 50% from the value before stent placement within 2 wk after drainage, without additional intervention.Complications that occurred within 7 d after stent placement were considered as early complications.Before drainage, the liver volume of each section(lateral and medial sections of the left liver and anterior and posterior sections of the right liver) was measured using computed tomography(CT) volumetry.Drained liver volume was calculated based on the volume of each liver section and the type of bile duct stricture(according to the Bismuth classification).Tumor volume, which was calculated by using CT volumetry, was excluded from the volume of each section.Receiver operating characteristic(ROC) analysis was performed to identify the optimal cutoff values for drained liver volume.In addition, factors associated with the effectiveness of drainage and early complications were evaluated.RESULTS:Multivariate analysis showed that drained liver volume [odds ratio(OR) = 2.92, 95%CI:1.648-5.197; P < 0.001] and impaired liver function(with decompensated liver cirrhosis)(OR = 0.06, 95%CI:0.009-0.426; P = 0.005) were independent factors contributing to the effectiveness of drainage.ROC analysis for effective drainage showed cutoff values of 33% of liver volume for patients with preserved liver function(with normal liver or compensated livercirrhosis)and 50%for patients with impaired liver function(with decompensated liver cirrhosis).The sensitivity and specificity of these cutoff values were82%and 80%for preserved liver function,and 100%and 67%for impaired liver function,respectively.Among patients who met these criteria,the rate of effective drainage among those with preserved liver function and impaired liver function was 90%and 80%,respectively.The rates of effective drainage in both groups were significantly higher than in those who did not fulfill these criteria(P<0.001 and P=0.02,respectively).Drainage-associated cholangitis occurred in 9 patients(12%).A smaller drained liver volume was associated with drainage-associated cholangitis(P<0.01).CONCLUSION:Liver volume drainage≥33%in patients with preserved liver function and≥50%in patients with impaired liver function correlates with effective biliary drainage in UMHBS.

Diagnosis of biliary strictures after liver transplantation:Which is the best tool?

AIM: To evaluate the diagnostic value of different indirect methods like biochemical parameters, ultrasound (US) analysis, CT-scan and MRI/MRCP in comparison with endoscopic retrograde cholangiography (ERC), for diagnosis of biliary complications after liver transplantation. METHODS: In 75 patients after liver transplantation, who received ERC due to suspected biliary complications, the result of the cholangiography was compared to the results of indirect imaging methods performed prior to ERC. The cholangiography showed no biliary stenosis (NoST) in 25 patients, AST in 27 and ITBL in 23 patients. RESULTS: Biliary congestion as a result of AST was detected with a sensitivity of 68.4% in US analysis (specificity 91%), of 71% in MRI (specificity 25%) and of 40% in CT (specificity 57.1%). In ITBL, biliary congestion was detected with a sensitivity of 58.8% in the US, 88.9%in MRI and of 83.3% in CT. However, as anastomotic or ischemic stenoses were the underlying cause of biliary congestion, the sensitivity of detection was very low. InMRI detected the dominant stenosis at a correct localization in 22% and CT in 10%, while US failed completely. The biochemical parameters, showed no significant difference in bilirubin (median 5.7; 4,1; 2.5 mg/dL), alkaline phosphatase (median 360; 339; 527 U/L) or gamma glutamyl transferase (median 277; 220; 239 U/L) levels between NoST, AST and ITBL.CONCLUSION: Our data confirm that indirect imaging methods to date cannot replace direct cholangiography for diagnosis of post transplant biliary stenoses. However MRI may have the potential to complement or precede imaging by cholangiography. Optimized MRCP-processing might further improve the diagnostic impact of this method.

Evaluation of fully covered self-expanding metal stents in benign biliary strictures and bile leaks

AIM: To investigate the use of fully covered metal stents in benign biliary strictures (BBS) and bile leaks. METHODS: We studied 17 patients, at Harbor-UCLA Medical center (Los Angeles), with BBS (n=12) and bile leaks (n=5) from July 2007 to February 2012 that had received placement of fully covered self-expanding metal stents (FCSEMs). Fourteen patients had endoscopic placement of VIABIL (Conmed, Utica, New York, United States) stents and three had Wallflex (Boston Scientific, Mass) stents. FCSEMS were 8 mm or 10 mm in diameter and 4 cm to 10 cm in length. Patients were followed at regular intervals to evaluate for symptoms and liver function tests. FCSEMS were removed after 4 or more weeks. Resolution of BBS and leak was documented cholangiographically following stent removal. Stent patency can be defined as adequate bile and contrast flow from the stent and into the ampulla during endoscopic retrograde cholangiopancreatography (ERCP) without clinical signs and/or symptoms of biliary obstruction. Criterion for bile leak resolution at ERCP is defined as absence of contrast extravasation from the common bile duct, cystic duct remanent, or gall blad-der fossa. Rate of complications such as migration, and instent occlusion were recorded. Failure of endoscopic therapy was defined as persistent biliary stenosis or continuous biliary leakage after 12 mo of stent placement. RESULTS: All 17 patients underwent successful FC- SEMS placement and removal. Etiologies of BBS included: cholecystectomies (n=8), cholelithiasis (n=2), hepatic artery compression (n=1), pancreatitis (n=2), and Whipple procedure (n=1). All bile leaks occurred following cholecystectomy. The anatomic location of BBS varied: distal common bile duct (n=7), common hepatic duct (n=1), hepaticojejunal anastomosis (n=2), right intrahepatic duct (n=1), and choledochoduo-denal anastomatic junction (n=1). All bile leaks were found to be at the cystic duct. Twelve of 17 patients had failed prior stent placement or exchange. Resolution of the biliary strictures and bile leaks was achieved in 16 of 17 patients (94%). The overall median stent time was 63 d (range 27-251 d). The median stent time for the BBS group and bile leak group was 62 ± 58 d (range 27-199 d) and 92 ± 81 d (range 48-251 d), respectively. All 17 patients underwent successful FCSEMS removal. Long term follow-up was obtained for a median of 575 d (range 28-1435 d). Complications occurred in 5 of 17 patients (29%) and included: migration (n=2), stent clogging (n=1), cholangitis (n=1), and sepsis with hepatic abscess (n=1). CONCLUSION: Placement of fully covered self-expanding metal stents may be used in the management of benign biliary strictures and bile leaks with a low rate of complications.

Endoscopic therapy of benign biliary strictures

Benign biliary strictures are being increasingly treated with endoscopic techniques. The benign nature of the stricture should be first confirmed in order to ensure appropriate therapy. Surgery has been the traditional treatment, but there is increasing desire for minimally invasive endoscopic therapy. At present, endoscopy has become the first line approach for the therapy of post- liver transplant anastomotic strictures and distal （Bismuth ! and I） post-operative strictures. Strictures related to chronic pancreatitis have proven more difficult to treat, and endoscopic therapy is reserved for patients who are not surgical candidates. The preferred endoscopic approach is aggressive treatment with gradual dilation of the stricture and insertion of multiple plastic stents. The use of uncovered self expandable metal stents should be discouraged due to poor long-term results. Treatment with covered metal stents or bioabsorbable stents warrants further evaluation. This area of therapeutic endoscopy provides an ongoing opportunity for fresh research and innovation.

Bilateral vs unilateral placement of metal stents for inoperable highgrade hilar biliary strictures: A systemic review and meta-analysis

BACKGROUND Bilateral vs unilateral biliary stenting is used for palliation in malignant biliary obstruction.No clear data is available to compare the efficacy and safety of bilateral biliary stenting over unilateral stenting.AIM To assess the efficacy and safety of bilateral vs unilateral biliary drainage in inoperable malignant hilar obstruction.METHODS PubMed,Embase,Scopus,and Cochrane databases,as well as secondary sources(bibliographic review of selected articles and major GI proceedings),were searched through January 2019.The primary outcome was the re-intervention rate.Secondary outcomes were a technical success,early and late complications,and stent malfunction rate.Pooled odds ratio(OR)and 95%confidence interval(CI)were calculated for each outcome.RESULTS A total of 9 studies were included(2 prospective Randomized Controlled Study,5 retrospective studies,and 2 abstracts),involving 782 patients with malignant hilar obstruction.Bilateral stenting had significantly lower re-intervention rate compared with unilateral drainage(OR=0.59,95%CI:0.40-0.87,P=0.009).There was no difference in the technical success rate(OR=0.7,CI:0.42-1.17,P=0.17),early complication rate(OR=1.56,CI:0.31-7.75,P=0.59),late complication rate(OR=0.91,CI:0.58-1.41,P=0.56)and stent malfunction(OR=0.69,CI:0.42-1.12,P=0.14)between bilateral and unilateral stenting for malignant hilar biliary strictures.CONCLUSION Bilateral biliary drainage had a lower re-intervention rate as compared to unilateral drainage for high grade inoperable malignant biliary strictures,with no significant difference in technical success,and early or late complication rates.

Role of endoscopic retrograde cholangiopancreatography inthe management of benign biliary strictures:What's new?

Benign biliary strictures comprise a heterogeneous group of diseases. The most common strictures amenable to endoscopic treatment are post-cholecystectomy, post-liver transplantation, related to primary sclerosing cholangitis and to chronic pancreatitis. Endoscopic treatment of benign biliary strictures is widely used as first line therapy, since it is effective, safe, noninvasive and repeatable. Endoscopic techniques currently used are dilation, multiple plastic stents insertion and fully covered self-expandable metal stents. The main indication for dilation alone is primary sclerosing cholangitis related strictures. In the vast majority of the remaining cases, temporary placement of multiple plastic stents with/without dilation is considered the treatment of choice. Although this approach is effective, it requires multiple endoscopic sessions due to the short duration of stent patency. Fully covered self-expandable metal stents appear as a good alternative to plastic stents, since they have an increased radial diameter, longer stent patency, easier insertion technique and similar efficacy. Recent advances in endoscopic technique and various devices have allowed successful treatment in most cases. The development of novel endoscopic techniques and devices is still ongoing.

Endoscopic ultrasonography can diagnose distal biliary strictures without a mass on computed tomography

AIM:To assess the diagnostic ability of endoscopic ultrasonography(EUS)for evaluating causes of dista biliary strictures shown on endoscopic retrograde chol angiopancreatography(ERCP)or magnetic resonance cholangiopancreatography(MRCP),even without iden tifiable mass on computed tomography(CT). METHODS:The diagnostic ability of EUS was retro spectively analyzed and compared with that of routine cytology(RC)and tumor markers in 34 patients with distal biliary strictures detected by ERCP or MRCP a Dokkyo Medical School Hospital from December 2005 to December 2008,without any adjacent mass or ec centric thickening of the bile duct on CT that could cause biliary strictures.Findings considered as benign strictures on EUS included preservation of the normasonographic layers of the bile duct wall,irrespective of the presence of a mass lesion.Other strictures were considered malignant.Final diagnosis of underlying diseases was made by pathological examination in 18 cases after surgical removal of the samples,and by clinical follow-up for>10 mo in 16 cases. RESULTS:Seventeen patients(50%)were finally di- agnosed with benign conditions,including 6"normal" subjects,while 17 patients(50%)were diagnosed with malignant disease.In terms of diagnostic ability,EUS showed 94.1%sensitivity,82.3%specificity,84.2% positive predictive value,93.3%negative predictive value(NPV)and 88.2%accuracy for identifying ma- lignant and benign strictures.EUS was more sensi- tive than RC(94.1%vs 62.5%,P=0.039).NPV was also better for EUS than for RC(93.3%vs 57.5%,P= 0.035).In addition,EUS provided significantly higher sensitivity than tumor markers using 100 U/mL as the cutoff level of carbohydrate antigen 19-9(94.1%vs 53%,P=0.017).On EUS,biliary stricture that was fi- nally diagnosed as malignant showed as a hypoechoic, irregular mass,with obstruction of the biliary duct and invasion to surrounding tissues. CONCLUSION:EUS can diagnose biliary strictures caused by malignant tumors that are undetectable on CT.Earlier detection by EUS would provide more therapeutic options for patients with early-stage pancreaticobiliary cancer.

Efficacy of multiple biliary stenting for refractory benign biliary strictures due to chronic calcifying pancreatitis

AIMTo investigate endoscopic therapy efficacy for refractory benign biliary strictures (BBS) with multiple biliary stenting and clarify predictors. METHODSTen consecutive patients with stones in the pancreatic head and BBS due to chronic pancreatitis who underwent endoscopic therapy were evaluated. Endoscopic insertion of a single stent failed in all patients. We used plastic stents (7F, 8.5F, and 10F) and increased stents at intervals of 2 or 3 mo. Stents were removed approximately 1 year after initial stenting. BBS and common bile duct (CBD) diameter were evaluated using cholangiography. Patients were followed for &ge; 6 mo after therapy, interviewed for cholestasis symptoms, and underwent liver function testing every visit. Patients with complete and incomplete stricture dilations were compared. RESULTSEndoscopic therapy was completed in 8 (80%) patients, whereas 2 (20%) patients could not continue therapy because of severe acute cholangitis and abdominal abscess, respectively. The mean number of stents was 4.1 &plusmn; 1.2. In two (20%) patients, BBS did not improve; thus, a biliary stent was inserted. BBS improved in six (60%) patients. CBD diameter improved more significantly in the complete group than in the incomplete group (6.1 &plusmn; 1.8 mm vs 13.7 &plusmn; 2.2 mm, respectively, P = 0.010). Stricture length was significantly associated with complete stricture dilation (complete group; 20.5 &plusmn; 3.0 mm, incomplete group; 29.0 &plusmn; 5.1 mm, P = 0.011). Acute cholangitis did not recur during the mean follow-up period of 20.6 &plusmn; 7.3 mo. CONCLUSIONSequential endoscopic insertion of multiple stents is effective for refractory BBS caused by chronic calcifying pancreatitis. BBS length calculation can improve patient selection procedure for therapy.

Radiofrequency and malignant biliary strictures:An update

Malignant biliary strictures are usually linked to different types of tumors,mainly cholangiocarcinoma, pancreatic and hepatocellular carcinomas. Palliative measures are usually adopted in patients with nonresectable or borderline resectable biliary disease. Stent placement is a well-known and established treatment in patients with unresectable malignancy. Intraductal radiofrequency ablation(RFA) represents a procedure that involves the use of a biliary catheter device, via an endoscopic approach. Indications for biliary RFA described in literature are: Palliative treatment of malignant biliary strictures, avoiding stent occlusion, ablating ingrowth of blocked metal stents, prolonging stent patency,ablating residual adenomatous tissue after endoscopic ampullectomy. In this mini-review we addressed focus on technical success defined as deployment of the RF catheter, virtually succeeded in all patients included in the studies. About efficacy, three main outcome measures have been contemplated: Biliary decompression and stent patency, survival. Existing studies suggest a beneficial effect on survival and stent patency with RFA, but current impression is limited because most of studies have been performed using a retrospective design, on diminutive and dissimilar cohorts of patients.

Common controversies in management of biliary strictures

Biliary strictures are caused by a heterogeneous group of benign and malignant conditions, each requiring a specific treatment approach. Management of biliary strictures often involves endoscopy either for definite treatment, as a bridge to surgery or for palliative purposes. Endoscopic treatment of various types of biliary strictures is not standardized and there are multiple areas of controversy regarding the best treatment options. These controversies are mainly due to lack of well-designed comparative studies to support a specific therapy. This paper reviews three common areas of controversy in the endoscopic management of biliary strictures. The areas discussed in this editorial include the role of biliary drainage in resectable malignant strictures and whether such drainage should be performed routinely prior to surgery, the best endoscopic palliation for unresectable hilar strictures and whether unilateral or bilateral stenting should be attempted, and the optimal endoscopic management for dominant strictures in patients with primary sclerosing cholangitis. The goal of this editorial is twofold. The first is to review the current literature on management of the aforementioned strictures and offer recommendations based on available evidence. The second goal is to highlight the gaps in our knowledge which in turn can encourage future research on these topics.

Hepatobiliary scintigraphy for detecting biliary strictures after living donor liver transplantation

AIM:To investigate the diagnostic accuracy of hepatobiliary scintigraphy(HBS) in detecting biliary strictures in living donor liver transplantation(LDLT) patients.METHODS:We retrospectively reviewed 104 adult LDLT recipients of the right hepatic lobe with duct-toduct anastomosis,who underwent HBS and cholangiography.The HBS results were categorized as normal,parenchymal dysfunction,biliary obstruction,or bile leakage without re-interpretation.The presence of biliary strictures was determined by percutaneous cholangiography or endoscopic retrograde cholangiopancreatography(ERCP).RESULTS:In 89 patients with biliary strictures,HBS showed biliary obstruction in 50 and no obstruction in 39,for a sensitivity of 56.2%.Of 15 patients with no biliary strictures,HBS showed no obstruction in 11,for a specificity of 73.3%.The positive predictive value(PPV) was 92.6%(50/54) and the negative predictive value(NPV) was 22%(11/50).We also analyzed the diagnostic accuracy of the change in bile duct size.The sensitivity,NPV,specificity,and PPV were 65.2%,27.9%,80% and 95%,respectively.CONCLUSION:The absence of biliary obstruction on HBS is not reliable.Thus,when post-LDLT biliary strictures are suspected,early ERCP may be considered.

Management issues in post living donor liver transplant biliary strictures

Biliary complications are common after living donor liver transplant(LDLT) although with advancements in surgical understanding and techniques, the incidence is decreasing. Biliary strictures are more common than leaks. Endoscopic retrograde cholangiopancreatography(ERCP) is the first line modality of treatment of post LDLT biliary strictures with a technical success rate of 75%-80%. Most of ERCP failures are successfully treated by percutaneous transhepatic biliary drainage(PTBD) and rendezvous technique. A minority of patients may require surgical correction. ERCP for these strictures is technically more challenging than routine as well post deceased donor strictures. Biliary strictures may increase the morbidity of a liver transplant recipient, but the mortality is similar to those with or without strictures. Post transplant strictures are short segment and soft, requiring only a few session of ERCP before complete dilatation. Long-term outcome of patients with biliary stricture is similar to those without stricture. With the introduction of new generation cholangioscopes, ERCP success rate may increase, obviating the need for PTBD and surgery in these patients.

Current endoscopic approach to indeterminate biliary strictures

Biliary strictures are considered indeterminate when basic work-up, including transabdominal imaging and endoscopic retrograde cholangiopancreatography with routine cytologic brushing, are non-diagnostic. Indeterminate biliary strictures can easily be mischaracterized which may dramatically affect patient's outcome. Early and accurate diagnosis of malignancy impacts not only a patient's candidacy for surgery, but also potential timely targeted chemotherapies. A significant portion of patients with indeterminate biliary strictures have benign disease and accurate diagnosis is, thus, paramount to avoid unnecessary surgery. Current sampling strategies have suboptimal accuracy for the diagnosis of malignancy. Emerging data on other diagnostic modalities, such as ancillary cytology techniques, single operator cholangioscopy, and endoscopic ultrasonography-guided fine needle aspiration, revealed promising results with much improved sensitivity.

Risk factors and clinical indicators for the development of biliary strictures post liver transplant:Significance of bilirubin

AIM To identify risk factors associated with the formation of biliary strictures post liver transplantation over a period of 10-year in Queensland.METHODS Data on liver donors and recipients in Queensland between 2005 and 2014 was obtained from an electronic patient data system.In addition,intra-operative and post-operative characteristics were collected and a logistical regression analysis was performed to evaluate their association with the development of biliary strictures.RESULTS Of 296 liver transplants performed,285(96.3%) were from brain dead donors.Biliary strictures developed in 45(15.2%) recipients.Anastomotic stricture formation(n = 25,48.1%) was the commonest complication,with 14(58.3%) of these occurred within 6-mo of transplant.A percutaneous approach or endoscopic retrograde cholangiography was used to treat 17(37.8%) patients with biliary strictures.Biliary reconstruction was initially or ultimately required in 22(48.9%) patients.In recipients developing biliary strictures,bilirubin was significantly increased within the first postoperative week(Day 7 total bilirubin 74 μmol/L vs 49 μmol/L,P = 0.012).In both univariate and multivariate regression analysis,Day 7 total bilirubin > 55 μmol/L was associated with the development of biliary stricture formation.In addition,hepatic artery thrombosis and primary sclerosing cholangitis were identified as independent risk factors.CONCLUSION In addition to known risk factors,bilirubin levels in the early post-operative period could be used as a clinical indicator for biliary stricture formation.

Endoscopic and retrograde cholangiographic appearance of hepaticojejunostomy strictures:A practical classifi cation

AIM:To study the endoscopic and radiological characteristics of patients with hepaticojejunostomy(HJ)and propose a practical HJ stricture classif ication.METHODS:In a retrospective observational study,a balloon-assisted enteroscopy(BAE)-endoscopic retrograde cholangiography was performed 44 times in 32 patients with surgically-altered gastrointestinal(GI)anatomy.BAE-endoscopic retrograde cholangio pancreatography(ERCP)was performed 23 times in 18 patients with HJ.The HJ was carefully studied with the endoscope and using cholangiography.RESULTS:The authors observed that the hepaticojejunostomies have characteristics that may allow these to be classif ied based on endoscopic and cholangiographic appearances:the HJ orif ice aspect may appear as small(type A)or large(type B)and the stricture may be short(type 1),long(type 2)and type 3,intrahepatic biliary strictures not associated with anastomotic stenosis.In total,7 patients had type A1,4 patients A2,one patient had B1,one patient had B(large orif ice without stenosis)and one patient had type B3.CONCLUSION:This practical classification allows for an accurate initial assessment of the HJ,thus potentially allowing for adequate therapeutic planning,as the shape,length and complexity of the HJ and biliary tree choice may mandate the type of diagnostic and thera-peutic accessories to be used.Of additional importance,a standardized classif ication may allow for better com-parison of studies of patients undergoing BAE-ERCP in the setting of altered upper GI anatomy.