A case report of carcinoma of the papilla of Vater associated with a hyperplasia-dysplasia-carcinoma sequence by pancreaticobiliary maljunction

BACKGROUND

Pancreaticobiliary maljunction (PBM) is a known risk factor for biliary tract cancer. However, its association with carcinoma of the papilla of Vater (PVca) remains unknown. We report a case with PVca that was thought to be caused by the hyperplasia-dysplasia-carcinoma sequence, which is considered a mechanism underlying PBM-induced biliary tract cancer.

CASE PRESENTATION

A 70-year-old woman presented with white stool and had a history of cholecystectomy for the diagnosis of a non-dilated biliary tract with PBM. Esophagogastroduodenoscopy revealed a tumor in the papilla of Vater, and PVca was histologically proven by biopsy. We finally diagnosed her with PVca concurrent with non-biliary dilated PBM (cT1aN0M0, cStage IA, according to the Union for International Cancer Control, 8th edition), and subsequently performed subtotal stomach-preserving pancreaticoduodenectomy. Pathological findings of the resected specimen revealed no adenomas and dysplastic and hyperplastic mucosae in the common channel slightly upstream of the main tumor, suggesting a PBM related carcinogenic pathway with hyperplasia-dysplasia-carcinoma sequence. Immunostaining revealed positivity for CEA. CK7 positivity, CK20 negativity, and MUC2 negativity indicated that this PVca was of the pancreatobiliary type. Genetic mutations were exclusively detected in tumors and not in normal tissues, and bile ducts from formalin-fixed paraffin-embedded samples included mutated-ERBB2 (Mutant allele frequency, 81.95%). Moreover, of the cell-free deoxyribonucleic acid (cfDNA) extracted from liquid biopsy mutated-ERBB2 was considered the circulating-tumor deoxyribonucleic acid (ctDNA) of this tumor.

CONCLUSIONS

Herein, we report the first case of PVca with PBM potentially caused by a "hyperplasia-dysplasia-carcinoma sequence" detected using immunostaining and next-generation sequencing. Careful follow-up is required if pancreaticobiliary reflux persists, considering the possible development of PVca.

A case of congenital biliary dilatation without pancreaticobiliary maljunction, so-called Type Ib according to Todani's classification

Congenital biliary dilatation (CBD) is a congenital malformation of focal dilatation of the extrahepatic bile ducts, including the common bile duct, and is often associated with pancreaticobiliary maljunction (PBM). In this article, we report a CBD case that presented with focal dilation of the common bile duct without PBM (Todani's classification type Ib). The patient was a 32-year-old man who visited a doctor with a chief complaint of abdominal distension. Computed tomography revealed cystic dilatation of the common bile duct, and the patient was referred to our institution. Magnetic resonance cholangiopancreatography showed cystic dilatation of the common bile duct with a maximum diameter of 7 cm; however, evaluating the presence of PBM was challenging. Endoscopic ultrasonography showed small gallstones and debris in the dilated common bile duct and no thickening of the gallbladder wall. Endoscopic retrograde cholangiopancreatography revealed no PBM or markedly elevated bile amylase levels. Based on these findings, the patient was diagnosed with Todani Type Ib CBD. Since this patient did not have pancreatobiliary reflux, it was unclear whether the risk of developing biliary tract cancer was high, and since the treatment was highly invasive, the decision was to follow up without surgical treatment.

Using machine learning models to predict the surgical risk of children with pancreaticobiliary maljunction and biliary dilatation

PURPOSE

To develop machine learning (ML) models to predict the surgical risk of children with pancreaticobiliary maljunction (PBM) and biliary dilatation.

METHODS

The subjects of this study were 157 pediatric patients who underwent surgery for PBM with biliary dilatation between January, 2015 and August, 2022. Using preoperative data, four ML models were developed, including logistic regression (LR), random forest (RF), support vector machine classifier (SVC), and extreme gradient boosting (XGBoost). The performance of each model was assessed via the area under the receiver operator characteristic curve (AUC). Model interpretations were generated by Shapley Additive Explanations. A nomogram was used to validate the best-performing model.

RESULTS

Sixty-eight patients (43.3%) were classified as the high-risk surgery group. The XGBoost model (AUC = 0.822) outperformed the LR (AUC = 0.798), RF (AUC = 0.802) and SVC (AUC = 0.804) models. In all four models, enhancement of the choledochal cystic wall and an abnormal position of the right hepatic artery were the two most important features. Moreover, the diameter of the choledochal cyst, bile duct variation, and serum amylase were selected as key predictive factors by all four models.

CONCLUSIONS

Using preoperative data, the ML models, especially XGBoost, have the potential to predict the surgical risk of children with PBM and biliary dilatation. The nomogram may provide surgeons early warning to avoid intraoperative iatrogenic injury.

Variations of the hepatic artery and bile duct in patients with pancreaticobiliary maljunction: Impact on postoperative outcomes

PURPOSE

Preoperative comprehension of the anatomical variations of the hepatic artery and bile duct is essential for safe laparoscopic surgery for pancreaticobiliary maljunction (PBM). This study aimed to investigate the impact of anatomical variations of the hepatic artery and bile duct on surgical technique and postoperative complications.

METHODS

We conducted a retrospective review of patients with PBM who underwent laparoscopic surgery at our institution between January 2014 and December 2022 to investigate anatomical variations in the hepatic artery and bile duct, surgical technique, and postoperative complications.

RESULTS

We included 112 patients with PBM, with a median age of 4 years (interquartile range, 0-55). Overall, 29 of 112 patients had an aberrant right hepatic artery (ARHA) running ventral to the common hepatic duct (CHD), and they underwent hepaticojejunostomy on the ventral side of the ARHA. Additionally, eight of 112 patients had an aberrant posterior hepatic duct (APHD), which was joined to the CHD in all but one case. The presence of APHD was associated with postoperative bile leak occurrence.

CONCLUSION

Performing hepaticojejunostomy ventral to the ARHA is important to prevent complications. Furthermore, APHD may be a risk factor for postoperative bile leak and requires careful bile duct plasty.

An Unusual Variant of Anomalous Pancreaticobiliary Junction

A 27-year-old previously healthy African American female presented to the Emergency Department with an acute onset of epigastric abdominal pain and nausea. Laboratory studies proved unremarkable. CT scan demonstrated intrahepatic and extrahepatic biliary ductal dilation with possible stones within the common bile duct. The patient was discharged with a surgery follow-up appointment. Laparoscopic cholecystectomy with intraoperative cholangiography was performed 3 weeks later due to concern for choledocholithiasis. The intraoperative cholangiogram showed multiple abnormalities, concerning for an infectious or inflammatory process. Magnetic resonance cholangiopancreatography (MRCP) demonstrated a suspected anomalous pancreaticobiliary junction and cystic lesion near the pancreatic head. Endoscopic retrograde cholangiopancreatography (ERCP) for cholangioscopy showed normal-appearing pancreaticobiliary mucosa with 3 tributaries directly from the pancreas entering the bile duct and an ansa orientation to the pancreatic duct. Biopsies of the mucosa were benign. Annual MRCP and MRI to assess for findings concerning for neoplasm given the anomalous pancreaticobiliary junction were recommended.

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.

Combination of UNet++ and ResNeSt to classify chronic inflammation of the choledochal cystic wall in patients with pancreaticobiliary maljunction

OBJECTIVES

The aim of this study was to establish an automatic classification model for chronic inflammation of the choledoch wall using deep learning with CT images in patients with pancreaticobiliary maljunction (PBM).

METHODS

CT images were obtained from 76 PBM patients, including 61 cases assigned to the training set and 15 cases assigned to the testing set. The region of interest (ROI) containing the choledochal lesion was extracted and segmented using the UNet++ network. The degree of severity of inflammation in the choledochal wall was initially classified using the ResNeSt network. The final classification result was determined per decision rules. Grad-CAM was used to explain the association between the classification basis of the network and clinical diagnosis.

RESULTS

Segmentation of the lesion on the common bile duct wall was roughly obtained with the UNet++ segmentation model and the average value of Dice coefficient of the segmentation model in the testing set was 0.839 ± 0.150, which was verified through fivefold cross-validation. Inflammation was initially classified with ResNeSt18, which resulted in accuracy = 0.756, sensitivity = 0.611, specificity = 0.852, precision = 0.733, and area under curve (AUC) = 0.711. The final classification sensitivity was 0.8. Grad-CAM revealed similar distribution of inflammation of the choledochal wall and verified the inflammation classification.

CONCLUSIONS

By combining the UNet++ network and the ResNeSt network, we achieved automatic classification of chronic inflammation of the choledoch in PBM patients and verified the robustness through cross-validation performed five times. This study provided an important basis for classification of inflammation severity of the choledoch in PBM patients.

ADVANCES IN KNOWLEDGE

We combined the UNet++ network and the ResNeSt network to achieve automatic classification of chronic inflammation of the choledoch in PBM. These results provided an important basis for classification of choledochal inflammation in PBM and for surgical therapy.

Transabdominal Ultrasound Evaluation of Pancreaticobiliary Maljunction in Children

ABSTRACT

The development of high-frequency ultrasound made the diagnosis of pancreaticobiliary maljunction (PBM) possible. However, no study has been performed to clarify the sensitivity and specificity of transabdominal ultrasound (TAUS) in the diagnosis of PBM. The purpose of this study was to evaluate the accuracy of TAUS in the diagnosis of pediatric PBM and to assess factors that may influence the accuracy of ultrasound. This was a prospective study and 43 patients with suspected PBM were enrolled. All of these patients underwent TAUS examination to detect the pancreaticobiliary ductal union. Final diagnoses were determined by endoscopic retrograde cholangiopancreatography or intraoperative cholangiography. Sensitivity and specificity were calculated. Fisher exact test was used to analyze the difference of sonographic features between false-negative group and true-positive group. Transabdominal ultrasound demonstrated 77.4% (95% confidence interval, 58.5%-89.7%) sensitivity and 100% (95% confidence interval, 69.9%-100%) specificity for PMB diagnosis. In the false-negative group, infant patients (71.4% vs 16.7%, P = 0.012), cystic dilatation of the common bile duct (CBD) (71.4% vs 16.7%, P = 0.012), and stenosis of the distal CBD (71.4% vs 16.7%, P = 0.012) were more frequently observed than in the true-positive group. On the other hand, the true-positive group showed a higher incidence of protein plugs than the false-negative group (62.5% vs 0%, P = 0.007). Transabdominal ultrasound may serve as a potential alternative detection modality for pediatric patients with suspected PBM. Nondetection of the anomaly may be attributed to factors, such as younger age, cystic dilatation of the CBD, and stenosis of the distal CBD.