Pancreaticobiliary Maljunctions in European Patients with Bile Duct Cysts: Results of the Multicenter Study of the French Surgical Association (AFC)

A novel deep learning radiopathomics model for predicting carcinogenesis promotor cyclooxygenase-2 expression in common bile duct in children with pancreaticobiliary maljunction: a multicenter study

OBJECTIVES

To develop and validate a deep learning radiopathomics model (DLRPM) integrating radiological and pathological imaging data to predict biliary cyclooxygenase-2 (COX-2) expression in children with pancreaticobiliary maljunction (PBM), and to compare its performance with single-modality radiomics, deep learning radiomics (DLR), and pathomics models.

METHODS

This retrospective study included 219 PBM patients, divided into a training set (n = 104; median age, 2.8 years, 75.0% females) and internal test set (n = 71; median age, 2.2 years, 83.1% females) from center I, and an external test set (n = 44; median age, 3.4 years, 65.9% females) from center II. Biliary COX-2 expression was detected using immunohistochemistry. Radiomics, DLR, and pathomics features were extracted from portal venous-phase CT images and H&E-stained histopathological slides, respectively, to build individual single-modality models. These were then integrated to develop the DLRPM, combining three predictive signatures. Model performance was evaluated using AUC, net reclassification index (NRI, for assessing improvement in correct classification) and integrated discrimination improvement (IDI).

RESULTS

The DLRPM demonstrated the highest performance, with AUCs of 0.851 (95% CI, 0.759-0.942) in internal test set and 0.841 (95% CI, 0.721-0.960) in external test set. In comparison, AUCs for the radiomics, DLR, and pathomics models were 0.532-0.602, 0.658-0.660, and 0.787-0.805, respectively. The DLRPM significantly outperformed three single-modality models, as demonstrated by the NRI and IDI tests (all p < 0.05).

CONCLUSION

The multimodal DLRPM could accurately and robustly predict COX-2 expression, facilitating risk stratification and personalized postoperative management in PBM. However, prospective multicenter studies with larger cohorts are needed to further validate its generalizability.

CRITICAL RELEVANCE STATEMENT

Our proposed deep learning radiopathomics model, integrating CT and histopathological images, provides a novel and cost-effective approach to accurately predict biliary cyclooxygenase-2 expression, potentially advancing individualized risk stratification and improving long-term outcomes for pediatric patients with pancreaticobiliary maljunction.

KEY POINTS

Predicting biliary COX-2 expression in pancreaticobiliary maljunction (PBM) is critical but challenging. A deep learning radiopathomics model achieved high predictive accuracy for COX-2. The model supports patient stratification and personalized postoperative management in PBM.

Diversity and heterogeneity in human pancreaticobiliary maljunction revealed by single-cell RNA sequencing

PURPOSE

The etiology and pathogenesis of pancreaticobiliary maljunction (PBM) remain unclear, thus a comprehensive investigation of cellular diversity and microenvironmental differences is pivotal to elucidate the mechanisms driving PBM.

METHODS

We performed single-cell RNA sequencing on bile duct tissues from six patients, including three with PBM and three without (non-PBM). Pathway enrichment, transcription factor analysis, and cell-cell communication were analyzed to explore cellular interactions and functional states.

RESULTS

A total of 90,996 single cells and 11 distinct cell lineages were identified, revealing significant differences in cellular composition between the two groups. PBM group was characterized by a higher proportion of endothelial cells and fibroblasts, while B and T cells were less abundant. Three subtypes of fibroblasts, antigen-presenting, inflammatory, and myofibroblastic cancer-associated fibroblasts, with the myofibroblast subtype being predominant in PBM. We found heightened activity of the WNT and TWEAK signaling pathways in PBM, as well as increased ligand-receptor interactions between fibroblasts and other cell types, including epithelial and endothelial cells.

CONCLUSION

Fibroblasts play a central role in driving fibrosis and tissue remodeling in PBM through specific signaling pathways. These insights provide a foundation for future therapeutic strategies aimed at modulating fibroblast activity to prevent or mitigate fibrosis in PBM.

Deep learning radiomics nomogram for preoperatively identifying moderate-to-severe chronic cholangitis in children with pancreaticobiliary maljunction: a multicenter study

BACKGROUND

Long-term severe cholangitis can lead to dense adhesions and increased fragility of the bile duct, complicating surgical procedures and elevating operative risk in children with pancreaticobiliary maljunction (PBM). Consequently, preoperative diagnosis of moderate-to-severe chronic cholangitis is essential for guiding treatment strategies and surgical planning. This study aimed to develop and validate a deep learning radiomics nomogram (DLRN) based on contrast-enhanced CT images and clinical characteristics to preoperatively identify moderate-to-severe chronic cholangitis in children with PBM.

METHODS

A total of 323 pediatric patients with PBM who underwent surgery were retrospectively enrolled from three centers, and divided into a training cohort (n = 153), an internal validation cohort (IVC, n = 67), and two external test cohorts (ETC1, n = 58; ETC2, n = 45). Chronic cholangitis severity was determined by postoperative pathology. Handcrafted radiomics features and deep learning (DL) radiomics features, extracted using transfer learning with the ResNet50 architecture, were obtained from portal venous-phase CT images. Multivariable logistic regression was used to establish the DLRN, integrating significant clinical factors with handcrafted and DL radiomics signatures. The diagnostic performances were evaluated in terms of discrimination, calibration, and clinical usefulness.

RESULTS

Biliary stones and peribiliary fluid collection were selected as important clinical factors. 5 handcrafted and 5 DL features were retained to build the two radiomics signatures, respectively. The integrated DLRN achieved satisfactory performance, achieving area under the curve (AUC) values of 0.913 (95% CI, 0.834-0.993), 0.916 (95% CI, 0.845-0.987), and 0.895 (95% CI, 0.801-0.989) in the IVC, and two ETCs, respectively. In comparison, the clinical model, handcrafted signature, and DL signature had AUC ranges of 0.654-0.705, 0.823-0.857, and 0.840-0.872 across the same cohorts. The DLRN outperformed single-modality clinical, handcrafted radiomics, and DL radiomics models, with all integrated discrimination improvement values > 0 and P < 0.05. The Hosmer-Lemeshow test and calibration curves showed good consistency of the DLRN (P > 0.05), and the decision curve analysis and clinical impact curve further confirmed its clinical utility.

CONCLUSIONS

The integrated DLRN can be a useful and non-invasive tool for preoperatively identifying moderate-to-severe chronic cholangitis in children with PBM, potentially enhancing clinical decision-making and personalized management strategies.

Impact of prior cholecystectomy on diagnosis and outcomes of choledochal cyst resection in adults

INTRODUCTION

The diagnosis of choledochal cysts in the adult population is complicated by the expected physiologic dilation of the common bile duct after cholecystectomy. We aimed to compare patients who underwent choledochal cyst resection based on cholecystectomy status.

METHODS

A retrospective analysis was conducted of patients who underwent choledochal cyst resection between 1/1/1998-12/31/2021. Patients were categorized based on whether they had undergone cholecystectomy prior to choledochal cyst diagnosis. Preoperative imaging characteristics, pathology findings, and outcomes were evaluated.

RESULTS

Amongst 119 patients who underwent excision, 58 (46 ​%) had and 69 (54 ​%) had not undergone prior cholecystectomy. Preoperative imaging demonstrated no difference in biliary tract diameter although a greater proportion of patients with a gallbladder in place had an anomalous pancreaticobiliary junction (55 ​% v 33 ​%, p ​< ​0.05). Biliary malignancy was observed in a greater proportion of patients with prior cholecystectomy although this was not statistically significant (5 ​% v 3 ​%; p ​= ​0.9). Rates of post-operative complications were statistically similar between patient cohorts.

DISCUSSION

Radiographic and clinical features were similar among patients who had and had not undergone cholecystectomy. Choledochal cyst patients should be managed uniformly regardless of cholecystectomy status.

Endoscopic retrograde cholangiopancreatography: A comprehensive review as a single diagnostic tool

Endoscopic retrograde cholangiopancreatography (ERCP) was initially introduced in clinical practice as diagnostic tool. However, the presence of adverse events and the development of non-invasive techniques, such as magnetic resonance cholangiopancreatography (MRCP) and endoscopic ultrasound (EUS), limited its role as a stand-alone diagnostic choice, modifying its role to the leader of therapeutic pancreatobiliary endoscopy. Despite technological advances, there are still conditions where non-invasive diagnostic modalities are inconclusive, such as indeterminate biliary and pancreatic duct strictures, primary sclerosing cholangitis functional stenoses, intraductal papillary mucinous neoplasms (IPMNs) and paediatric indications, such as congenital anatomical abnormalities. This narrative review aimed to identify and analyse indications of diagnostic ERCP, without the need for therapeutic manipulations.

Pancreaticobiliary Reflux with Normal and Relatively Long Common Channels Causing Cholelithiasis and Acute Pancreatitis in Children

Background and Aims: Pancreaticobiliary maljunction (PBMJ) has a long common channel (CC) that causes pancreaticobiliary reflux (PBR), which has been implicated in gallstones, cholangiocarcinoma, and pancreatitis. By contrast, PBR has occurred in cases with normal and longer CCs than normal but shorter than PBMJ. This pathophysiology has been primarily reported in adults and rarely in children. We sometimes observe this pathophysiology in children with pancreatitis and cholelithiasis. Herein, we report the clinical figures on the diagnosis of children with PBR in normal and relatively long CCs. Patients and Methods: This study included seven children who complained of refractory pancreatitis and cholelithiasis diagnosed with PBR in normal and relatively long CCs at our institution from August 2018 to September 2024. We measured the lengths of their CCs and sphincter of Oddi muscles via endoscopic retrograde cholangiopancreatography (ERCP) and cholangiography. In addition, amylase and lipase levels in bile juice were measured. Results: All seven children demonstrated elevated amylase and lipase levels in bile juice obtained from gallbladder drainage and/or the common bile duct. ERCP and cholangiography indicated 2.2-5.5-mm lengths of CCs in their cases, which are normal lengths in two cases and relatively longer (0.3-1.1 mm: mean 0.6 mm) than the normal upper limit of CC in children in five cases, with their CCs shorter than the sphincters of Oddi. All children underwent extrahepatic bile duct resection and bilio-jejunal anastomosis, demonstrating no clinical symptom recurrence postoperatively. Conclusions: Some children with cholelithiasis and pancreatitis exhibit normal and relatively long CCs, causing PBR and inducing gastrointestinal diseases. Careful investigation by ERCP and cholangiography focused on the CC length, and pancreatic enzyme level assessments in bile juice are useful for diagnosing PBR in children with cholelithiasis and refractory pancreatitis.

Treatment of pancreaticobiliary maljunction by minimally invasive endoscopic common channel sphinctertomy: Analysis of 35 cases

BACKGROUND

Patients with pancreaticobiliary maljunction (PBM) have a common channel (CC) that is too long, causing the Oddi sphincter not to directly affect the pancreaticobiliary junction. As a result, reflux between pancreatic juice and bile occurs, causing various pathological changes in the bile duct or pancreas. Exploring the application and mechanism of minimally invasive endoscopic shortening of the pancreatic bile duct CC channel in PBM has become particularly important, providing patients with another treatment option.

AIM

To investigate the clinical efficacy and safety of minimally invasive endoscopic common channel sphinctertomy (CCEST) in the treatment of patients with PBM.

METHODS

The clinical data of 35 PBM patients treated by minimally invasive CCEST were analyzed, and there were BP type (n = 19) and PB type (n = 16) PBM. All 35 patients underwent CCEST with the help of endoscopic retrograde cholangiopancreatography, and the therapeutic effects and complications of minimally invasive CCEST in PBM patients were analyzed.

RESULTS

A total of 35 patients were diagnosed with PBM, of whom 12 were male and 23 were female. The patients ranged in age from 3 to 89 years, with a mean age of (46 ± 26.38) years. CCEST was performed in all patients to reduce the length of the CC. Among the 35 patients with PBM, 18 (51.43%) had combined biliary and pancreatic duct stones and underwent intraoperative lithotripsy. First-time ERCP stone extraction was successful in 14 patients, with a success rate of 78% (14/18). One week after minimally invasive intervention therapy, the serum biochemistry and C-reactive protein (CRP) and bile amylase in the 35 patients showed a significant decrease compared to the preoperative levels (P < 0.05). Post-ERCP pancreatitis was observed in five patients, but no serious complications such as postoperative bleeding, gastrointestinal perforation, and severe pancreatitis occurred after symptomatic treatment. After a mean follow-up period of (22.05 ± 10.67) mo in the 35 patients, one patient was diagnosed with carcinoma of the bile duct and treated by surgery, and four were treated by ERCP again because of stone recurrence and achieved satisfactory efficacy. The total effective rate of the treatment was 88.6% (31/35).

CONCLUSION

PBM patients often present with an insidious onset. ERCP is a valuable procedure for the diagnosis of PBM. CCEST effectively improves biliopancreatic drainage in early-stage PBM patients by reducing the length of the common biliopancreatic confluence channel. CCEST is a safe and effective minimally invasive intervention for the treatment of PBM patients.

Clinical presentations and outcomes of pancreaticobiliary maljunction in different pediatric age groups

BACKGROUND

Pancreaticobiliary maljunction (PBM) is a congenital defect, with risk of developing various pancreaticobiliary and hepatic complications. The presentations of PBM in children and adults are believed to be different, but studies on PBM children of different age groups are limited. This study was to evaluate clinicopathologic characteristics and outcomes in PBM children of different ages.

METHODS

A total of 166 pediatric patients with PBM were reviewed retrospectively. Clinicopathological, imaging, laboratory, surgical, and follow-up data were collected and analyzed. The patients were divided into three age groups, namely, group A (< 1 year, n = 31), group B (1-3 years, n = 63), and group C (> 3 years, n = 72).

RESULTS

The major clinical manifestation was jaundice in group A and abdominal pain and vomiting in groups B and C. Acute pancreatitis was more often seen in group C than group A. The length of common channel was significantly longer in group C than group A, while the maximum diameter of common bile duct in group C was smaller than that in group A. Cholangitis and cholecystitis were more commonly performed in groups B and C, while hepatic fibrosis in group A. Whether preoperatively or postoperatively, group C was more likely to have elevated serum amylase, while groups A and B were more likely to present with abnormal liver function indicators, including the increase of aspartate transaminase, alanine transaminase, and gamma-glutamyl transpeptidase.

CONCLUSION

Presentation of PBM varies among different pediatric age groups, thus suggesting that targeted management should be carried out according to these differences.

A Unique Type or Variation of Bile Duct Cyst in a 9-Year-Old Girl:A Remarkable Case Study

Patients with bile duct cysts require careful radiological assessment of the hepatobiliary system prior to surgical intervention. This clinical case is uncommon with an atypical clinical presentation and radiological findings. According to the most widely used classification of choledochal cysts, this case presents a combination of Type I and Type IV of choledochal cyst (CC) combining the form of extra, intrahepatic bile ducts and cystic duct dilations.

Application of imaging techniques in pancreaticobiliary maljunction

Imaging techniques are useful tools in the diagnosis and treatment of pancreaticobiliary maljunction (PBM). PBM is a precancerous lesion often relative to the disease of the pancreas and biliary tract, for example, cholecystolithiasis, protein plugs, and pancreatitis. For patients with PBM, early diagnosis and timely treatment are highly important, which is largely dependent on imaging techniques. The continuous development of imaging techniques, including endoscopic retrograde cholangiopancreatography, magnetic resonance cholangiopancreatography, computed tomography, ultrasound, and intraoperative cholangiography, has provided appropriate diagnostic and therapeutic tools for PBM. Imaging techniques, including non-invasive and invasive, have distinct advantages and disadvantages. The purpose of this paper is to review the application of various imaging techniques in the diagnosis and treatment of PBM.

Pancreatobiliary Maljunction-associated Gallbladder Cancer Is as Common in the West, Shows Distinct Clinicopathologic Characteristics and Offers an Invaluable Model for Anatomy-induced Reflux-associated Physio-chemical Carcinogenesis

OBJECTIVE

To determine the associations of pancreatobiliary maljunction (PBM) in the West.

BACKGROUND

PBM (anomalous union of common bile duct and pancreatic duct) is mostly regarded as an Asian-only disorder, with 200X risk of gallbladder cancer (GBc), attributed to reflux of pancreatic enzymes. Methods: Radiologic images of 840 patients in the US who underwent pancreatobiliary resections were reviewed for PBM and contrasted with 171 GBC cases from Japan.

RESULTS

Eight % of the US GBCs (24/300) had PBM (similar to Japan; 15/ 171, 8.8%), in addition to 1/42 bile duct carcinomas and 5/33 choledochal cysts. None of the 30 PBM cases from the US had been diagnosed as PBM in the original work-up. PBM was not found in other pancreatobiliary disorders. Clinicopathologic features of the 39 PBM-associated GBCs (US:24, Japan:15) were similar; however, comparison with non-PBM GBCs revealed that they occurred predominantly in females (F/M = 3); at younger (<50-year-old) age (21% vs 6.5% in non-PBM GBCs; P = 0.01); were uncommonly associated with gallstones (14% vs 58%; P < 0.001); had higher rate of tumor-infiltrating lymphocytes (69% vs 44%; P = 0.04); arose more often through adenoma-carcinoma sequence (31% vs 12%; P = 0.02); and had a higher proportion of nonconventional carcinomas (21% vs 7%; P = 0.03). Conclusions: PBM accounts for 8% of GBCs also in the West but is typically undiagnosed. PBM-GBCs tend to manifest in younger age and often through adenoma-carcinoma sequence, leading to unusual carcinoma types. If PBM is encountered, cholecystectomy and surveillance of bile ducts is warranted. PBM-associated GBCs offer an invaluable model for variant anatomy-induced chemical (reflux-related) carcinogenesis.

Progress in research of pancreaticobiliary maljunction and biliary dilatation

Pancreaticobiliary maljunction (PBM) is a congenital anomaly that is defined as a junction of the pancreatic and bile ducts located outside the duodenal wall during the embryonic stage, resulting in bile and pancreatic juice reflux and corresponding clinical symptoms. PBM is a high risk factor for cholangiocarcinoma. PBM can occur with or without biliary dilatation (BD). Early diagnosis of PBM can prevent complications. Ultrasonography, magnetic resonance imaging, multi-slice spiral computed tomography, endoscopic ultrasonography, endoscopic retrograde cholangiopancreatography, and cholangiopancreatography are important modalities for diagnosis of this disease. The standard surgical procedure for PBM with BD is dilated cholangiectomy and choledochoenteroreconstruction. Cholecystectomy should be performed as early as possible for PBM without BD.

Retrospective Analysis of the Accuracy of High-Frequency Ultrasound for Pancreaticobiliary Maljunction in Pediatrics at a Single Center

OBJECTIVE

To determine the clinical value of high-frequency ultrasonography (US) in the evaluation and diagnosis of pancreaticobiliary maljunction (PBM) among children.

METHODS

The clinical subjects consisted of 31 pediatric patients who were diagnosed with PBM from January 2015 to May 2021 in Fujian Provincial Maternity and Children's Hospital. The primary outcomes included diagnosis accuracy, imaging characteristics of each type of PBM based on JSPBM, time length of operation, and cost of service. Secondary outcomes were the serum amylase and bilirubin levels.

RESULTS

The diagnostic accuracy of US was 90.3% and comparable to the other imaging methods-MRCP (82.6%), IOC (79.2%), and ERCP (100%), respectively. The time length of operation and direct cost were significantly lower than other imaging pathways. Stenotic type (A) is associated with a high internal diameter of CBD, and dilated channel type (C) presents increased internal diameter and length of CC as well as internal diameter of PD. There were higher levels of the serum bilirubin seen in type A and of serum amylase in type C compared with others.

CONCLUSION

High-frequency US is a safe, cost-effective, and non-invasive imaging tool for the diagnosis and evaluation of PBM in pediatrics.

Application of Embedding Hepaticojejunostomy in Children with Pancreaticobiliary Maljunction Without Biliary Dilatation

Background: To investigate the effect of embedded hepaticojejunostomy in children with pancreaticobiliary maljunction (PBM) without biliary dilatation. Materials and Methods: The clinical data of 10 patients with nondilated PBM from February 2017 to July 2020 were retrospectively analyzed. Perioperative liver function indexes were compared. Results: All patients were diagnosed by magnetic resonance cholangiopancreatography (MRCP) combined with intraoperative cholangiography. There were 5 cases of Komi type I and 5 cases of type II; the diameter of the common bile duct was 4-9 mm (median: 6 mm); and the length of the common channel was 5-15 mm (median: 9.25 mm). The procedure for one patient with common duct stones was converted to open surgery. Laparoscopic cholecystectomy, common bile duct resection, and embedded hepaticojejunostomy were successfully performed in all 10 cases. The average operation time was 225 ± 96.64 min, and the intraoperative blood loss was 2-5 mL. The mean time to oral intake was 3.5 ± 1.65 days (range: 2-5 days), and the mean hospitalization duration was 6.2 ± 2.44 days (range: 5-8 days). The differences in liver function indexes in the perioperative period were statistically significant (P < .05). The patients were followed-up for 13 to 54 months (median: 40 months). All patients grew well and there was no bile duct dilatation, calculus, or cirrhosis on B-ultrasound examinations. Conclusions: The clinical manifestations of nondilated PBM are often concealed, and preoperative MRCP was important for obtaining a diagnosis. Laparoscopic cholecystectomy, common bile duct resection, and embedded hepaticojejunostomy are feasible for treating nondilated PBM.

Pediatric biliary disorders: Multimodality imaging evaluation with clinicopathologic correlation

The spectrum of pathologies affecting the biliary tree in the pediatric population varies depending on the age of presentation. While in utero insults can result in an array of anatomic variants and congenital anomalies in newborns, diverse acquired biliary pathologies are observed in older children. These acquired pathologies display different presentations and consequences than adults. Multimodality imaging assessment of the pediatric biliary system is requisite to establishing an appropriate management plan. Awareness of the imaging features of the various biliary pathologies and conveying clinically actionable information is essential to facilitate appropriate patient management. In this paper, we will illustrate the anatomy and embryology of the pediatric biliary system. Then, we will provide an overview of the imaging modalities used to assess the biliary system. Finally, we will review the unique features of the pediatric biliary pathologies, complemented by histopathologic correlation and discussions of clinical management.

De novo somatic mutations and KRAS amplification are associated with cholangiocarcinoma in a patient with a history of choledochal cyst

BACKGROUND/PURPOSE

Choledochal cysts are congenital dilations of the bile ducts, and are associated with an increased risk of malignant transformation. The purpose of this study is to report the outcomes of a large series of patients with choledochal cysts and to highlight our analysis of one patient who developed malignancy after cyst resection.

METHODS

We conducted a retrospective review of patients <18 years of age with a choledochal cyst who underwent surgical resection between 1995 and 2018. Molecular testing of resected choledochal cyst specimens using the UCSF500 gene panel was performed on three patients including a 3-month-old boy and a 7-year-old girl who have remained cancer-free, and a 16-year-old girl who subsequently developed cholangiocarcinoma less than two years after resection.

RESULTS

One patient of the 48 included in our study developed cholangiocarcinoma after choledochal cyst resection. We observed de novo somatic mutations in TP53 and RBM10, and KRAS amplification in this patient's tumor.

CONCLUSIONS

In our series, the rate of malignancy after choledochal cyst resection was low. One patient developed de novo mutations in the remnant bile ducts after cyst resection. While it is a rare occurrence, the risk of malignancy following cyst resection supports the need for lifelong surveillance.

LEVEL OF EVIDENCE

IV.

Choledochal malformations in adults in the Netherlands: Results from a nationwide retrospective cohort study

BACKGROUND AND AIMS

Patients with a choledochal malformation, formerly described as cysts, are at increased risk of developing a cholangiocarcinoma and resection is recommended. Given the low incidence of choledochal malformation (CM) in Western countries, the incidence in these countries is unclear. Our aim was to assess the incidence of malignancy in CM patients and to assess postoperative outcome.

METHODS

In a nationwide, retrospective study, all adult patients who underwent surgery for CM between 1990 and 2016 were included. Patients were identified through the Dutch Pathology Registry and local patient records and were analysed to determine the incidence of malignancy, as well as postoperative mortality and morbidity.

RESULTS

A total of 123 patients with a CM were included in the study (Todani Type I, n = 71; Type II, n = 10; Type III, n = 3; Type IV, n = 27; unknown, n = 12). Median age was 40 years (range 18-70) and 81% were female. The majority of patients (99/123) underwent extrahepatic bile duct resection, with additional liver parenchyma resections in eight patients, only exploration in two, and a local cyst resection in eight patients. Postoperative 30-day mortality was 2% (2/123) and limited to patients who underwent liver resection. Severe morbidity occurred in 24%. In 14 of the 123 patients (11%), a malignancy was found in the resected specimen. One patient developed a periampullary malignancy 7 years later.

CONCLUSIONS

In a large Western series of CM patients, 11% were found to have a malignancy. This justifies resection in these patients, despite the risk of morbidity (24%) and mortality (2%).

Complex Pancreaticobiliary Maljunction with Pancreas Divisum and Obstructive Pseudocyst

Pancreaticobiliary maljunction (PBM) is the congenital junction of the bile and pancreatic ducts into a common channel located anatomically outside of the duodenal wall. The complex type (Type D) is the rarest type and occurs in conjunction with other pancreaticobiliary anomalies. We present a case of complex PBM with pancreas divisum presenting as acute pancreatitis and obstructive symptoms secondary to a pancreatic pseudocyst. Surgical management is discussed, as complex type PBM is most predisposed to post-operative complications.

Imaging of Pancreaticobiliary Maljunction

Pancreaticobiliary maljunction (PBM) is a congenital malformation in which the pancreatic and bile ducts join outside the duodenal wall, usually forming a long common channel. A major issue in patients with PBM is the risk of biliary cancer. Because the sphincter of Oddi does not regulate the pancreaticobiliary junction in PBM, pancreatic juice frequently refluxes into the biliary tract and can cause various complications, including biliary cancer. Most cancers arise in the gallbladder or dilated common bile duct, suggesting that bile stasis is related to carcinogenesis. Early diagnosis and prophylactic surgery to reduce the risk of cancer are beneficial. The diagnosis of PBM is made mainly on the basis of imaging findings. The development of diagnostic imaging modalities such as multidetector CT and MR cholangiopancreatography has provided radiologists with an important role in diagnosis of PBM and its complications. Radiologists should be aware of PBM despite the fact that it is rare in non-Asian populations. In this review, the authors present an overview of PBM with emphasis on diagnosis and management of PBM and its complications. For early diagnosis, the presence of extrahepatic bile duct dilatation or gallbladder wall thickening may provide a clue to PBM with or without biliary dilatation, respectively. The pancreaticobiliary anatomy should be closely examined if imaging reveals these findings. Radiologists should also carefully evaluate follow-up images in PBM patients even years after prophylactic surgery because residual bile ducts remain at risk for cancer.^©RSNA, 2020.

Survey of the attitudes of hepatopancreatobiliary surgeons in northern Europe to resection of choledochal cysts in asymptomatic Western adults

Background

Todani type 1 and 4 choledochal cysts are associated with a risk of developing cholangiocarcinoma. Resection is usually recommended, but data for asymptomatic Western adults are sparse. The aim of this study was to investigate diagnostic interpretation and attitudes towards resection of bile ducts for choledochal cysts in this subgroup of patients across northern European centres.

Methods

Thirty hepatopancreatobiliary centres were provided with magnetic resonance cholangiopancreatograms and asked to discuss the management of six cases: asymptomatic non‐Asian women, aged 30 or 60 years, with variable common bile duct (CBD) dilatations and different risk factors in the setting of a multidisciplinary team (MDT). The Fleiss κ value was calculated to estimate overall inter‐rater agreement.

Results

For all case scenarios combined, 83·3 and 86·7 per cent recommended resection for a CBD of 20 and 26 mm respectively, compared with 19·4 per cent for a CBD of 13 mm (P < 0·001). For patients aged 30 and 60 years, resection was recommended in 68·5 and 57·8 per cent respectively (P = 0·010). There was a trend towards recommending resection in the presence of a common channel, most pronounced in the 60‐year‐old patient. High amylase levels in the CBD aspirate led to recommendations to resect, but only for the 13‐mm CBD dilatation. There were no differences related to centre size or region. MDT discussion was associated with recommendations to resect. Inter‐rater agreement was 73·3 per cent (κ = 0·43, 95 per cent c.i. 0·38 to 0·48).

Conclusion

The inter‐rater agreement to resect was intermediate, and the recommendation was dependent mainly on the diameter of the CBD dilatation.

A degenerate Todani Ia choledochal cyst in a patient with pancreas divisum

Bile duct cysts represent congenital abnormalities associated with biliopancreatic maljunction that may undergo malignant degeneration. We report herein the case of a 72-year-old male patient with cholangitis. MR-cholangiography and abdominal CT revealed a mass at the biliary-pancreatic-duodenal crossroads, extrahepatic biliary dilation up to 38 mm, and pancreas divisum. Gastroscopy found an infiltrative bulbar mucosa with adenocarcinoma in biopsy samples, and extrinsic bulging of the second duodenal portion. Endoscopic ultrasound showed a choledochal cystic dilation with solid contents, and FNA findings were nonspecific. ERCP confirmed an adenomatous papilla at the lower portion of the extrinsic formation, and a large cystic, saccular dilation of extrahepatic bile ducts (Todani Ia). Fistulotomy was required for deep cannulation of the proximal biliary tract, and attention was drawn to extruding polypoid lesions originating in the biliary epithelium, identified in biopsies as adenoma with dysplasia. Finally, a diagnosis was made of advanced adenocarcinoma in choledochal cyst.

Choledochal cysts: Similarities and differences between Asian and Western countries

Choledochal cysts (CCs) are rare bile duct dilatations, intra-and/or extrahepatic, and have higher prevalence in the Asian population compared to Western populations. Most of the current literature on CC disease originates from Asia where these entities are most prevalent. They are thought to arise from an anomalous pancreaticobiliary junction, which are congenital anomalies between pancreatic and bile ducts. Some similarities in presentation between Eastern and Western patients exist such as female predominance, however, contemporary studies suggest that Asian patients may be more symptomatic on presentation. Even though CC disease presents with an increased malignant risk reported to be more than 10% after the second decade of life in Asian patients, this risk may be overstated in Western populations. Despite this difference in cancer risk, management guidelines for all patients with CC are based predominantly on observations reported from Asia where it is recommended that all CCs should be excised out of concern for the presence or development of biliary tract cancer.

IL-33 overexpression in gallbladder cancers associated with pancreatobiliary maljunction

AIMS

To investigate whether genetic or inflammatory pro-oncogenic factors are relevant to the increased risk of gallbladder cancers in patients with pancreaticobiliary maljunction (PBM).

METHODS AND RESULTS

Mutations in KRAS exon 2 were examined by a highly sensitive, droplet digital PCR platform using surgically resected specimens of PBM-associated (n = 31) and non-associated gallbladder cancers (n = 49). The tissue expression of IL-6 and IL-33, which are suspected to promote biliary carcinogenesis, was analysed by quantitative real-time PCR and in-situ hybridisation. The incidence of KRAS mutations was similarly low in PBM-associated (five of 32 cases; 16%) and non-associated cancers (four of 49 cases; 8%) (P = 0.272). The tissue expression of IL-33 mRNA, but not IL-6 mRNA, was significantly higher in PBM-associated gallbladder cancers than in gallbladder cancers without PBM (P = 0.004). A similar degree of IL-33 overexpression was also observed in the background non-cancerous mucosa in cases of PBM-associated gallbladder cancers, and was significantly greater than that in PBM cases with cholecystitis alone (P < 0.001). The results of in-situ hybridisation indicated that the source of IL-33 production in PBM-associated carcinomas was the endothelium, cancer cells and non-neoplastic biliary epithelium. In a combined PBM-associated and non-associated cohort, IL-33 overexpression in gallbladder cancers correlated with less aggressive features (e.g. a lower pT stage and longer overall survival), similar to recently reported findings on large-duct cholangiocarcinomas.

CONCLUSIONS

KRAS mutations do not appear to be associated with a high risk of malignancy in PBM, while IL-33 overexpression may provide a pro-oncogenic microenvironment in the gallbladder mucosa of patients with PBM.

Surgical Ampullectomy with Complete Resection of the Common Bile Duct: a New Procedure for Radical Resection of Non-invasive Ampulloma with Biliary Extension

Extension of ampulloma into the lower common bile duct (CBD) is observed in up to 30% of cases. This biliary extension can prevent complete tumor resection thus is considered as a contraindication for endoscopic and even surgical ampullectomy. For ampullomas associated with a prolonged biliary extension, a pancreaticoduodenectomy is associated with a high morbidity and can be considered as an overtreatment for a benign neoplasm. The present study describes a new surgical approach including ampullectomy with complete resection of the intrapancreatic CBD and restoration of both biliary and pancreatic flow by two separate anastomoses. This procedure was performed in seven patients for a non-invasive ampulloma with a 25- to 70-mm CBD involvement. No patients died and three developed postoperative complications. Resection was R0 in all patients but one. With a 24-month median follow-up (range = 3-84), no patients developed pancreatic insufficiency or tumor recurrence.