Occult pancreaticobiliary reflux in gallbladder cancer and benign gallbladder diseases

Pancreatobiliary reflux increases macrophage-secreted IL-8 and activates the PI3K/NFκB pathway to promote cholangiocarcinoma progression

BACKGROUND

Persistent pancreaticobiliary reflux (PBR) is associated with a high risk of biliary malignancy. This study aimed to evaluate the proportion of PBR in biliary tract diseases and mechanisms by which PBR promoted cholangiocarcinoma progression.

METHODS

Overall 227 consecutive patients with primary biliary tract disease participated in this study. The amylase levels in the collected bile were analyzed. The mechanisms underlying the effect of high-amylase bile on bile duct epithelial and cholangiocarcinoma cells progression were analyzed. The source of interleukin-8 (IL-8) and its effects on the biological functions of cholangiocarcinoma cells were investigated.

RESULTS

The bile amylase levels in 148 of 227 patients were higher than the upper serum amylase limit of 135 IU/L. PBR was significantly correlated with sex, pyrexia, and serum gamma-glutamyl transferase (GGT) levels in the patient cohort. High-amylase bile-induced DNA damage and genetic differences in the transcript levels of the gallbladder mucosa and facilitated the proliferation and migration of bile duct cancer cells (HUCCT1 and QBC939 cells). The concentration of many cytokines increased in high-amylase bile. IL-8 is secreted primarily by macrophages via the mitogen-activated protein kinase pathway and partially by bile duct epithelial cells. IL-8 promotes the progression of HUCCT1 and QBC939 cells by regulating the expression of epithelial-mesenchymal transition-associated proteins and activating the phosphatidylinositol 3-kinase/nuclear factor kappa-B pathway.

CONCLUSIONS

PBR is one of the primary causes of biliary disease. IL-8 secreted by macrophages or bile duct epithelial cells stimulated by high-amylase bile promotes cholangiocarcinoma progression.

Age and incidence of occult pancreaticobiliary reflux in patients with benign gallbladder diseases

BACKGROUND

Occult pancreaticobiliary reflux (OPBR) has a significant correlation with diseases of the gallbladder and biliary system. This study examined the incidence of OPBR by age in patients with benign gallbladder diseases.

METHODS

We assessed 475 patients with benign gallbladder diseases who underwent surgery at Shanghai East Hospital from December 2020 to December 2021. Bile samples collected during surgery were tested for amylase. Patients with bile amylase >110 U/L (n = 64) were classified as the OPBR group; the rest (n = 411) as controls.

RESULTS

Of the participants, 375 had gallbladder stone (GS), 170 had gallbladder polyp (GP), and 49 had gallbladder adenomyomatosis (GA). The OPBR group was generally older, with OPBR incidence increasing with age, peaking post-45. Rates by age were: 4.9% (<35), 5.2% (35-44), 20.7% (45-54), 22.5% (55-64) and 17.6% (≥65), mainly in GS patients. ROC analysis for predicting OPBR by age yielded an area under the curve of 0.656, optimal cut-off at 45 years. Logistic regression indicated age > 45, GP, male gender, and BMI ≥ 24 kg*m-2 as independent OPBR predictors in GS patients. Based on these variables, a predictive nomogram was constructed, and its effectiveness was validated using the ROC curve, calibration curve and decision curve analysis (DCA). Further stratification revealed that among GS patients ≤ 45, concurrent GA was an OPBR risk; for > 45, it was GP and male gender.

CONCLUSIONS

The incidence of OPBR in GS patients is notably influenced by age, with those over 45, especially males without GP, being at heightened risk.

Identification of changes in bile composition in pancreaticobiliary reflux based on liquid chromatography/mass spectrometry metabolomics

INTRODUCTION

Pancreaticobiliary reflux (PBR) can induce gallstone formation; however, its pathogenic mechanism remains unclear. In this study, we explored the mechanism of PBR by the non-targeted metabolomic analysis of bile in patients with PBR.

OBJECTIVE

The aim of this study was to investigate the pathogenic mechanism in PBR by the non-targeted metabolomic analysis of bile collected during surgery.

METHODS

Sixty patients who underwent gallstone surgery at our center from December 2020 to May 2021 were enrolled in the study. According to the level of bile amylase, 30 patients with increased bile amylase ( > 110 U/L) were classified into the PBR group, and the remaining 30 patients were classified into the control group (≤ 110 U/L). The metabolomic analysis of bile was performed.

RESULTS

The orthogonal projections to latent structure-discriminant analysis of liquid chromatography mass spectrometry showed significant differences in bile components between the PBR and control groups, and 40 metabolites were screened by variable importance for the projection value (VIP > 1). The levels of phosphatidylcholine (PC) and PC (20:3(8Z,11Z,14Z)/14:0) decreased significantly, whereas the levels of lysoPC (16:1(9z)/0:0), lysoPC (15:0), lysoPC (16:0), palmitic acid, arachidonic acid, leucine, methionine, L-tyrosine, and phenylalanine increased.

CONCLUSIONS

Significant differences in bile metabolites were observed between the PBR and control groups. Changes in amino acids and lipid metabolites may be related to stone formation and mucosal inflammation.

Preliminary exploration of method for screening efficacy markers compatibility in TCM prescriptions based on Q-markers: Anti-inflammatory activity of Dachaihu decoction as an example

ETHNOPHARMACOLOGICAL RELEVANCE

Dachaihu Decoction (DD), a classic Chinese herbal prescription, is composed of radix of Bupleurum chinense DC. (Chaihu), radix of Scutellaria baicalensis Georgi (Huangqin), radix of Paeonia lactiflora Pall. (Baishao), rhizoma of Pinellia ternata (Thunb.) Breit. (Banxia), fructus of Citrus aurantium L. (Zhishi), rhizoma of Zingiber officinale Rosc. (Shengjiang), fructus of Ziziphus jujuba Mill. (Dazao) and rhizoma of Rheum officinale Baill. (Dahuang). DD has the traditional effects of soothing the liver, relieving depression and clearing heat from the stomach, and is mainly used to treat heat stagnation in the liver and stomach.

AIM OF THE STUDY

Dachaihu decoction (DD), a classic prescription commonly used in clinical practice for the treatment of pancreatitis and cholecystitis. Although its pharmacological effects are clear, the efficacy components and mechanism of action remain intricate and difficult to clarify.

MATERIALS AND METHODS

The action targets and components of the anti-inflammatory activity of DD were predicted by network pharmacology; the effective components and targets were verified by HPLC and qPCR; the efficacy markers of DD were further screened by in vitro experiments; the pharmacological value of DD and its components compatibility were evaluated by in vitro experiments.

RESULTS

The key targets MMP9, JAK2, MAP2K1 and NR3C1 were screened by network pharmacology; HPLC analysis showed that paeoniflorin, naringin, hesperidin, neohesperidin, baicalin, wogonoside, baicalein and saikosaponin B₂ were identified as potential efficacy markers of DD; molecular docking combined with qPCR verification suggested that baicalin, naringin, neohesperidin, hesperidin and baicalein and wogonoside had certain ability to regulate above targets; in vitro studies revealed that paeoniflorin, naringin, hesperidin, neohesperidin, baicalin, wogonoside, baicalein and saikosaponin B₂ could inhibit the release of NO, pancreatic lipase and α-glucosidase; after comprehensive comparison and analysis, naringin, hesperidin, neohesperidin, baicalin, wogonoside, baicalein and saikosaponin B₂ were selected as the efficacy markers of DD; in vivo studies indicated that DD and its efficacy markers (components compatibility) had definite therapeutic effects on guinea pigs with cholecystitis.

CONCLUSIONS

The efficacy markers of DD including naringin, hesperidin, neohesperidin, baicalin, wogonoside, baicalein and saikosaponin B₂ can be used as components compatibility to exert anti-inflammatory activity. In addition, a method for obtaining the compatibility of efficacy markers by simplifying the prescription is initially established.

Occult pancreaticobiliary reflux is a pathogenic factor of some benign biliary diseases and gallbladder cancer

BACKGROUND

Pancreaticobiliary maljunction (PBM) is a well-known high-risk factor for biliary malignant tumors because of constant pancreaticobiliary reflux (PBR). However, the impact of occult pancreaticobiliary reflux (OPR), which is characterized by high bile amylase levels in individuals with anatomically normal pancreaticobiliary junction, on biliary diseases remains unclear. The aim of this study was to assess the correlation between OPR and biliary diseases.

METHODS

We enrolled 94 consecutive patients with normal pancreaticobiliary junction and primary biliary diseases confirmed by magnetic resonance cholangiopancreatography. We prospectively collected patients' bile samples and measured bile amylase levels. We investigated the incidence of OPR and the difference in bile amylase levels among these patients and assessed the correlation between high bile amylase levels (HBAL) and benign or malignant biliary diseases, as well as the OPR risk factors.

RESULTS

The incidence of OPR was 36.6% in patients with benign biliary diseases, 26.7% in those with cholangiocarcinoma and 62.5% in those with gallbladder cancer. The median bile amylase level tended to be higher in patients with gallbladder cancer than in those with benign biliary diseases, but there was no significant difference (165.5 IU/L vs. 23.0 IU/L, P = 0.212). The prevalence of an HBAL with bile amylase levels of 1000-7500 IU/L was similar in patients with gallbladder cancer and benign biliary diseases. However, the incidence of HBAL with bile amylase levels greater than 7500 IU/L was significantly higher in patients with gallbladder cancer than in those with benign biliary diseases (37.5% vs. 4.2%, P = 0.012). Multivariate logistic regression analysis revealed that choledocholithiasis was an independent risk factor for OPR.

CONCLUSIONS

OPR can occur in benign and malignant biliary diseases, and it may be a pathogenic factor for some benign biliary diseases and a high-risk factor for gallbladder cancer. There is a correlation between choledocholithiasis and OPR.

Relationship between high bile juice amylase levels and chronic bacterial infections in patients with gallbladder cancer

Purpose

Pancreatic enzyme reflux into the biliary tract is associated with chronic inflammation and increased cellular proliferation in the biliary epithelium, leading to biliary carcinoma. We evaluated the relationship between high bile juice amylase levels and biliary microflora in patients with malignant gallbladder lesions.

Methods

In this retrospective study, 25 gallbladder specimens were obtained from patients with gallbladder cancer to evaluate amylase levels and perform bacterial culture. The samples were divided into high and low amylase groups and culture-positive and negative groups for analysis. Bile juice amylase 3 times higher than the normal serum amylase level (36–128 IU/L) was considered high.

Results

The number of positive cultures was higher in the high amylase group than in the low amylase group, but the difference was insignificant. There were no differences in other clinicopathological factors. Sixteen patients showed positive culture results; Escherichia coli and Klebsiella spp. were the most common gram-negative bacteria, whereas Enterococcus and Streptococcus spp. were the most common gram-positive bacteria. Age and bile juice amylase levels were significantly higher in the culture-positive group than in the culture-negative group. The incidence of bacterial resistance to cephalosporins was 6.25%–35.29%, and this incidence was particularly high for lower-generation cephalosporins.

Conclusion

Bacteria in gallbladder were identified more frequently when the amylase level was high. High amylase levels in the gallbladder can be associated with caused chronic bacterial infections with occult pancreaticobiliary reflux, potentially triggering gallbladder cancer.

Free fatty acids and triglyceride change in the gallbladder bile of gallstone patients with pancreaticobiliary reflux

Background

Pancreaticobiliary reflux (PBR) causes chronic inflammation of the gallbladder mucosa and changes in the bile components, which are known to promote gallstone formation. This study aimed to investigate the bile biochemistry changes in gallstone patients with PBR and provide new clues for research on the involvement of PBR in gallstone formation.

Methods

Patients undergoing surgery for gallstones between December 2020 and May 2021 were eligible for inclusion. The bile biochemistry (including amylase, lipase, triglyceride, cholesterol, free fatty acids [FFAs], alanine aminotransferase [ALT], aspartate aminotransferase [AST], alkaline phosphatase [ALP], and γ-glutamyl transferase [γ-GT]) of the included gallstone patients was analysed to determine correlations with PBR.

Results

In this study, 144 gallstone patients who underwent surgery were enrolled. Overall, 15.97 % of the patients had an increased bile amylase level, which was associated with older age and significantly higher bile levels of ALP, lipase, triglyceride, and FFAs. Positive correlations were observed between amylase and lipase, triglyceride, FFAs levels in the gallbladder bile. However, the bile levels of triglyceride, FFAs, and lipase were positively correlated with each other only in the PBR group and showed no significant correlation in the control (N) group. In addition, elevated bile FFAs levels were found to be an independent risk factor for gallbladder wall thickening.

Conclusions

In conclusion, PBR-induced increase in FFAs and triglyceride in the gallbladder bile is a cause of gallstone formation, and an increase in bile ALP suggests the presence of cholestasis in PBR.

Common bile duct pressure in patients with and without cholelithiasis: A case-control study

BACKGROUND

The reflux of pancreatic enzymes into the bile duct and the gallbladder is an abnormal phenomenon that plays a role in lithogenesis and carcinogenesis. Because the pressure of the common bile duct depends on the pressures of the sphincter of Oddi, its dysfunction would be reflected in an increase in the pressure of the common bile duct in patients with cholelithiasis. The objective of this study was to measure the pressures of the common bile duct in patients with and without cholelithiasis and to relate them to the presence of pancreatobiliary reflux.

METHODS

A prospective case-control study was designed. The study universe was constituted by all patients undergoing total gastrectomy for gastric cancer stages I and II over 30 months. The primary outcome measure was to establish differences between common bile duct pressures in patients with and without cholelithiasis.

RESULTS

Common bile duct pressures in patients with gallstones showed a significant elevation (16.9 mmHg) compared to patients without gallstones (3.3 mm Hg) (p < 0.0001). These pressures correlated with the levels of amylase and lipase in gallbladder bile; higher levels were found in patients with gallstones compared to patients without gallstones (P < 0.0001).

CONCLUSIONS

Common bile duct pressure in patients with cholelithiasis was significantly higher compared to patients without cholelithiasis leading to pancreatobiliary reflux.

Standardized Surgical Management for Cystic Dilation of the Bile Ducts Based on Clinical and Pathological Studies: A Narrative Review

The surgical method of complete/radical cyst excision plus Roux-en-Y hepaticojejunostomy remains the primary therapy and the only effective treatment for cystic dilation of the bile ducts (CDBDs). However, the incidence of long-term postoperative complications is still high, as is the reoperation rate, and the potential for postoperative malignant transformation still exists. In recent years, significant progress has been made in understanding the pathogenic mechanism and pathological changes of adult CDBDs. Based on which, the surgical procedures for CDBDs have been revised to further improve their effectiveness. The purpose of this review is to systematically summarize the latest concepts of the etiology and pathogenic mechanism and the pathological changes of adult CDBDs. Based on the findings of these clinical and pathological studies, a comprehensive theoretical system in the surgical treatment of CDBDs has been established, which corrects many previous theoretical misunderstandings. The specific surgical method for each type of CDBDs and the key technical notes are also described in detail. Using these principles, treatment outcomes for CDBDs can be significantly improved, and the current high complication rate, reoperation rate, and rate of postoperative malignant transformation can be reduced.

Telomere length of gallbladder epithelium is shortened in patients with congenital biliary dilatation: measurement by quantitative fluorescence in situ hybridization

BACKGROUND

Congenital biliary dilatation (CBD) is a congenital malformation involving both dilatation of the extrahepatic bile duct and pancreaticobiliary maljunction. Persistent reflux of pancreatic juice injures the biliary tract mucosa, resulting in chronic inflammation and higher rates of carcinogenesis in the biliary tract, including the gallbladder. Telomeres are repetitive DNA sequences located at the ends of chromosomes. Chromosomal instability due to telomere dysfunction plays an important role in the carcinogenesis of many organs. This study was performed to determine whether excessive shortening of telomeres occurs in the gallbladder mucosa of patients with CBD.

METHODS

Resected gallbladders were obtained from 17 patients with CBD, ten patients with cholecystolithiasis without pancreatic juice reflux, and 17 patients with normal gallbladders (controls) (median age of each group of patients: 37, 50, and 53 years, respectively). The telomere lengths of the gallbladder epithelium were measured by quantitative fluorescence in situ hybridization using tissue sections, and the normalized telomere-to-centromere ratio (NTCR) was calculated.

RESULTS

The NTCRs in the CBD, cholecystolithiasis, and control groups were 1.24 [interquartile range (IQR) 1.125-1.52], 1.96 (IQR 1.56-2.295), and 1.77 (IQR 1.48-2.53), respectively. The NTCR in the CBD group was significantly smaller than that in the cholecystolithiasis and control groups (p = 0.003 and 0.004, respectively), even in young patients.

CONCLUSIONS

Our findings indicate that telomere shortening in the gallbladder mucosa plays an important role in the process of carcinogenesis in patients with CBD. These results support the recommendation of established guidelines for prophylactic surgery in patients with CBD because CBD is a premalignant condition with excessive telomere shortening.

Gallbladder mucosal lesions associated with high biliary amylase irrespective of pancreaticobiliary maljunction

BACKGROUND

Previous studies have focused on the presence of reflux in selected cohorts with pancreaticobiliary maljunction (PBM), but little is known regarding the wider incidence of occult reflux and associated mucosal changes. We aimed to correlate gallbladder mucosal abnormalities with objective evidence of PBM and occult pancreaticobiliary reflux (PBR) in an Australian population undergoing cholecystectomy.

METHODS

Patients undergoing cholecystectomy between September 2010 and September 2012 were eligible for inclusion. Demographic and pre-operative clinical data were collated and entered into a pre-defined database. Operative cholangiograms were routinely performed and the presence of PBM noted. Gallbladder bile samples were analysed for bilirubin (<20 µmol/L), amylase (<100 U/L) and lipase (<70 U/L) levels. Evidence of PBR was correlated with gallbladder mucosal findings.

RESULTS

A total of 305 cholecystectomies were performed for biliary colic (73%), choledocholithiasis (9%), cholecystitis (8.4%) and pancreatitis (6.4%). A total of 12.7% had cholangiographic evidence of PBM and 11.9% possessed gallbladder mucosal changes. Overall, 7.7% had increased biliary amylase, which was associated with significantly higher rates of gallbladder intestinal metaplasia (33% versus 8.6%; P = 0.012). Elevated biliary amylase was also higher in patients with prior pancreatitis (P = 0.02) or choledocholithiasis (P < 0.01). The presence of PBM did not predict for the presence of PBR.

CONCLUSION

PBR is associated with an increased frequency of gallbladder mucosal metaplasia, irrespective of the presence of PBM. Objectively identified reflux represents an additional indication for cholecystectomy but the long-term consequences for extra-hepatic biliary malignancy remain unknown and warrant further investigation. Methods of objectively identifying PBR pre-operatively require further investigation.

Common bile duct stones associated with pancreatobiliary reflux and disproportionate bile duct dilatation

Occult pancreatobiliary reflux (PBR) in patients with a normal pancreatobiliary junction has been studied by various methods, but the exact etiology, mechanisms, and implications of this reflux have not yet been clarified. The aim of this study was to investigate the degree of PBR and patterns of biliary ductal dilatation in patients with acute calculous cholangitis by endoscopic retrograde cholangiopancreatography (ERCP).We retrospectively evaluated the degree of PBR and pattern of bile duct dilatation in patients with acute calculous cholangitis due to distal CBD (common bile duct) stones (Group A) as compared with patients with malignant CBD obstruction due to distal CBD cancer (Group B). All related data were prospectively collected. Bile juice was aspirated at the proximal CBD for measurement of biliary amylase and lipase before the injection of contrast dye. The diameters of the CBD and the peripheral intrahepatic duct (IHD) were calculated after contrast dye injection. Patients with pancreatobiliary maljunction and/or gallstone pancreatitis were excluded from the study.ERCP was performed on 33 patients with calculous cholangitis (Group A) and 12 patients with malignant CBD obstruction (Group B). Mean levels of bile amylase and lipase were significantly higher (P < .05) in group A (1387 and 6737 U/l, respectively) versus those in group B (32 and 138 U/l, respectively). Thirty patients in group A (90.9%) showed disproportionate dilatation (i.e., CBD was and IHD was not dilated), whereas only 4 patients in group B (33%) showed disproportionate dilatation.The results of this study suggest that patients with calculous cholangitis exhibit PBR that is associated with disproportionate bile duct dilatation.

New concept: cellular senescence in pathophysiology of cholangiocarcinoma

Cholangiocarcinoma, a malignant tumor arising in the hepatobiliary system, presents with poor prognosis because of difficulty in its early detection/diagnosis. Recent progress revealed that cellular senescence may be involved in the pathophysiology of cholangiocarcinoma. Cellular senescence is defined as permanent growth arrest caused by several cellular injuries, such as oncogenic mutations and oxidative stress. "Oncogene-induced" and/or stress-induced senescence may occur in the process of multi-step cholangiocarcinogenesis, and overexpression of a polycomb group protein EZH2 may play a role in the escape from, and/or bypassing of, senescence. Furthermore, senescent cells may play important roles in tumor development and progression via the production of senescence-associated secretory phenotypes. Cellular senescence may be a new target for the prevention, early diagnosis, and therapy of cholangiocarcinoma in the near future.

Elevated bile amylase level without pancreaticobiliary maljunction is a risk factor for gallbladder carcinoma

BACKGROUND

Elevated bile amylase level in patients with pancreaticobiliary maljunction (PBM) or high confluence of pancreaticobiliary ducts (HCPBD) is well known as a risk factor for gallbladder carcinoma (GBC) development. However, the effects of occult pancreaticobiliary reflux (OPR), a condition characterized by high bile amylase level in the presence of an anatomically normal pancreaticobiliary junction, on GBC development remain unclear. The aim of this study was to assess the relationship between OPR and GBC.

METHODS

Clinicopathological data of 52 patients who were preoperatively diagnosed with gallbladder (GB) tumor (22 malignant, 30 benign) were retrospectively reviewed. All of the patients underwent preoperative endoscopic retrograde cholangiopancreatography to evaluate pancreaticobiliary junction morphology and bile amylase level. The relationship between the histological diagnosis of GB lesions, and pancreaticobiliary junction morphology and bile amylase level were investigated.

RESULTS

Pancreaticobiliary maljunction, HCPBD, and normal pancreaticobiliary junction (NPJ) were identified in 12, nine, and 31 patients, respectively. The rates of GBC in patients with PBM, HCPBD, and NPJ were 58% (7/12), 67% (6/9), and 29% (9/31), respectively. Of the 31 patients with NPJ, 22 had OPR and nine of these had GBC. None of the patients with NPJ and normal bile amylase level had GBC. Additionally, among patients with NPJ, bile amylase level was significantly higher in patients with GBC than in patients with benign tumors.

CONCLUSIONS

Occult pancreaticobiliary reflux, like PBM and HCPBD, is a risk factor for GBC development.

Idiopathic perforation of acalculous gallbladder after insertion of a transpapillary pancreatic stent

Endoscopic retrograde pancreatocholangiography (ERCP) is associated with many types of adverse events (AEs) but idiopathic perforation of the gallbladder (IPGB) is very rare. Pancreatobiliary reflux is one of the factors involved with occurrence of IPGB 1. Here we present a case of acalculous gallbladder perforation as an AE following the insertion of an indwelling endoscopic nasal pancreatic drainage (ENPD) tube (a pancreatic stent) to obtain pancreatic fluid. In this case, acute pancreatobiliary reflux might have been caused by the insertion of the ENPD-tube.

Predictive Factors of Biliary Tract Cancer in Anomalous Union of the Pancreaticobiliary Duct

The assessment of malignancies associated with anomalous union of the pancreaticobiliary duct (AUPBD) is essential for the design of appropriate treatment strategies. The aim of the present study is to measure the incidence of AUPBD-related pancreaticobiliary malignancy and to identify predictive factors. This retrospective cohort study included cases of 229 patients with AUPBD between January 1999 and December 2013. The impact of bile duct dilatation on the incidence of AUPBD-related pancreaticobiliary disease was measured, and predictive factors were evaluated.Among 229 patients with AUPBD, 152 had common bile duct dilatation (≥10 mm) (dilated group) and 77 did not (<10 mm) (nondilated group). Intrahepatic cholangiocarcinoma occurred more frequently in the nondilated group than in the dilated group (3.9% vs 0%; P < 0.05). By contrast, no significant difference in the incidence of extrahepatic cholangiocarcinoma was observed between the 2 groups (1.3% vs 3.9%; P = 0.271). By univariate analysis, age, type of AUPBD, and the level of pancreatic enzymes refluxed in the bile duct were associated with occurrence of biliary tract cancers. In multivariate analysis, age ≥45 years (odds ratio [OR] 1.042, 95% confidence interval [CI] 1.011-1.073, P < 0.05), P-C type (OR 3.327, 95% CI 1.031-10.740, P < 0.05), and a high level of biliary lipase (OR 4.132, 95% CI 1.420-12.021, P < 0.05) showed a significant association with AUPBD-related biliary tract cancer.Intrahepatic cholangiocarcinoma may occur more frequently in AUPBD patients without bile duct dilatation. Age ≥45 years, P-C type, and biliary lipase level ≥45,000 IU/L are significantly associated with AUPBD-related biliary tract cancer.

Sphincter of Oddi Dysfunction and the Formation of Adult Choledochal Cyst Following Cholecystectomy: A Retrospective Cohort Study

To determine the causes underlying the formation of adult choledochal cyst.Anomalous pancreaticobiliary junction is the most widely accepted theory regarding the etiology of choledochal cyst. However, choledochal cysts have been found in patients in the absence of this anomaly. Because the number of adult patients with choledochal cyst is increasing, it is important to address this controversy.Bile amylase levels in the cysts of 27 patients (8 males and 19 females) who had undergone cholecystectomy were retrospectively evaluated.The average age of the 27 patients was 45.8 ± 10.1 years and the majority (85.2%) were diagnosed with Todani type I cysts. None of the patients had dilatation of the common bile duct prior to surgery. There were 6 (22.2%) patients with anomalous pancreaticobiliary junction. However, amylase levels did not significantly differ between patients with and without this anomaly (P = 0.251). According to bile amylase levels, pancreatobiliary reflux was present in 21 (77.8%) patients. The mean amylase level significantly differed in patients with pancreatobiliary reflux (23,462 ± 11,510 IU/L) and those without (235 ± 103 IU/L) (P < 0.001). In patients with pancreatobiliary reflux, only 4 patients had anomalous pancreaticobiliary junction. That is, the majority of patients (17/21, 81%) having pancreatobiliary reflux did not have an anomalous junction of the pancreatic and biliary ducts.Since the only explanation for pancreatobiliary reflux in patients with a normal pancreaticobiliary junction is sphincter of Oddi dysfunction, we proposed that the formation of adult choledochal cyst is mainly due to sphincter of Oddi dysfunction.

Long-term follow-up may be needed for pancreaticobiliary reflux in healthy adults

PURPOSE

The reflux of pancreatic enzymes into the biliary tract is associated with chronic inflammation and increases cellular proliferation of the biliary epithelium, leading to biliary carcinoma. The aim of this study is to detect the incidence of occult pancreaticobiliary reflux (OPBR) in patients who underwent elective cholecystectomy.

METHODS

Forty-seven patients with symptomatic gallstones who underwent cholecystectomy were recruited for this study. The gallbladder bile samples were obtained from the specimen of gallbladder and the amylase level was measured. The immunohistochemistry of p53, SMAD4 and Ki-67 were performed for the detection of metaplasia and dysplasia.

RESULTS

Biliary amylase was higher than the serum amylase in 10 patients (group A, 15,402.66 ± 33,592.43 IU/L; group B, 13.06 ± 18.12 IU/L). The mean age was 67.2 years in group A and 51.2 in group B (P < 0.01). The ratio of male to female was 1:2.3 and 1:1.8 in group A and B, respectively (P = 0.297). Eight patients in group A and thirteen patients in group B had inflammation (P = 0.014). The positive results of the Ki-67 test were exhibited in five cases in each group (P = 0.024).

CONCLUSION

Results from the study indicate that the age was older, degree of inflammation and positive rate of Ki-67 were higher when OPBR was suspected. In conclusion, the patients with OPBR would need long-term follow-up, because the OPBR can cause dysplasia and the reflux of pancreatic juice may be considered as a risk factor for extrahepatic bile duct carcinoma.

Diagnosis and management of gallbladder cancer

Gallbladder cancer (GBC) is a rather uncommon disease, but at the time when it gives symptoms it has usually reached no longer curable stage. Therefore, all attempts must be made to make the diagnosis earlier to have better opportunity for cure. The author searched PubMed, and reviewed literatures on diagnoses and treatment of GBC.

Japanese clinical practice guidelines for pancreaticobiliary maljunction

There have been no clinical guidelines for the management of pancreaticobiliary maljunction (PBM). The Japanese Study Group on Pancreaticobiliary Maljunction (JSPBM) has proposed to establish clinical practice guidelines on how to deal with PBM, with the support of the Japan Biliary Association (JBA). Because the body of evidence-based literature is relatively small, we decided to create guidelines based on the consensus of experts, using the medical literature for reference. A total of 46 clinical questions (CQs) were considered by the members of the editorial committee responsible for the guidelines. The CQs covered distinct aspects of PBM: (1) Concepts and Pathophysiology (10 CQs); (2) Diagnosis (10 CQs); (3) Pancreatobiliary complications (9 CQs); and (4) Treatments and prognosis (17 CQs). Statements and comments for each CQ were prepared by the guidelines committee members and collaborating partners. The CQs were completed after review by members of the editorial committee, meetings of this committee, public comments on the homepages of the JSPBM and the JBA, public hearings, and assessment and approval by the guidelines evaluation board. PBM includes cases where the bile duct is dilated (PBM with biliary dilatation) and those in which it is not (PBM without biliary dilatation). In these guidelines, PBM with biliary dilatation is defined as being identical to congenital biliary dilatation of Todani type I (except for type Ib) and type IV-A, both of which are accompanied by PBM in almost all cases. These guidelines are created to provide assistance in the clinical practice of PBM management; their contents focus on clinical utility, and they include general information on PBM to make this disease more widely recognized.

Many faces of pancreaticobiliary reflux

Pancreaticobiliary reflux may occur either as a result of an anatomically abnormal pancreaticobiliary junction or because of a functionally impaired sphincter despite a normal radiological appearance. It is associated with a wide spectrum of biliary diseases, including gall bladder and bile duct carcinoma. Pancreaticobiliary maljunction and related biliary reflux have been studied extensively in Southeast Asian populations and associations with choledochal cyst and biliary malignancy defined. However, reflux in the absence of ductal malunion has only been described relatively recently and its significance with respect to biliary malignancy requires clarification. We present four cases of pancreaticobiliary reflux to demonstrate the varied associations of this under-recognized disorder and review the related management issues.

Current knowledge on pancreaticobiliary reflux in normal pancreaticobiliary junction

Knowledge on pancreaticobiliary reflux in normal pancreaticobiliary junction and their pathologic implications has experienced tremendous progress during the last few years. This article reviews the current knowledge on this condition and its pathological implications on gallbladder diseases. Many publications with different levels of evidence were found supporting biliary carcinogenesis associated with pancreaticobiliary reflux in normal and abnormal pancreaticobiliary junction. Also, there are many publications supporting the common occurrence of pancreaticobiliary reflux in normal pancreaticobiliary junction, and sphincter of Oddi dysfunction as the most plausible cause of this condition. Although an important body of research has been published regarding pancreaticobiliary reflux in normal pancreaticobiliary junction and their clinical significance, the current evidence does not fully support what has been suggested. The reflux of pancreatic enzymes into the bile tract and gallbladder is a fascinating subject of study which is open to active research. The final demonstration of the pathophysiology and consequences of PBR in NPBL and support by evidence level type I would constitute a major breakthrough in the understanding and eventually in the treatment of gallbladder diseases.

Pancreaticobiliary reflux in patients with a normal pancreaticobiliary junction: Pathologic implications

Knowledge on pancreaticobiliary reflux in normal pancreaticobiliary junction and its pathologic implications has experienced tremendous progress during the last few years. This editorial reviews the current knowledge on this condition and its pathological implications on gallbladder diseases. The following aspects were defined appropriate for discussion: (1) Evidence of carcinogenesis associated with pancreaticobiliary reflux; (2) Evidence of pancreaticobiliary reflux in normal pancreaticobiliary junction; and (3) Evidence of sphincter of Oddi (SO) dysfunction as a cause of pancreaticobiliary reflux in normal pancreaticobiliary junction. The articles reviewed were selected and classified according to five levels of evidence: LevelI, meta-analysis double-blind randomized clinical trials, Level II, cohort non-blinded studies and non-randomized clinical trials, Level III, good quality case-control studies and non-randomized cohort studies, Level IV, case series and poor quality case-control studies, and Level V, case report articles and experts’ opinion. Evidence levels II, III, IV and V were found to support biliary carcinogenesis associated with pancreaticobiliary reflux in normal and abnormal pancreaticobiliary junction. The same levels of evidence were found to support the common occurrence of pancreaticobiliary reflux in normal pancreaticobiliary junction, and SO dysfunction as the most plausible cause of this condition. Although an important body of research has been published regarding pancreaticobiliary reflux in normal pancreaticobiliary junction and its clinical significance, the current evidence does not fully support what has been suggested. Studies with evidence level I have not been undertaken. This is a fascinating subject of study, and if finally supported by evidence level I, the importance of this condition will constitute a major breakthrough in biliary pathology.

Progress in research of occult pancreatobiliary reflux

Increasing knowledge regarding pancreaticobiliary maljunction (PBM) has led researchers to find that pancreatobiliary reflux (flow of pancreatic juice into the biliary tract) occurs not only in PBM patients but also in individuals with a normal pancreaticobiliary junction (occult pancreatobiliary reflux, OPR). The functional disorders of the sphincter of Oddi have been proposed as a possible cause for OPR. Some studies have found that OPR is a high risk factor for gallbladder cancer. The incidence of choledochal stones is higher in patients with OPR than in those without OPR. In this article, we review the progress in research of OPR.

Papillary hyperplasia of the gallbladder in pancreaticobiliary maljunction represents a senescence-related lesion induced by lysolecithin

Cellular senescence, an irreversible growth arrest, is considered to play as safeguard against malignant progression, though such a mechanism is speculative in human carcinogenesis. In gallbladder carcinoma, cholecystolithiasis and pancreaticobiliary maljunction (PBM) are major risk factors. Here, by using 113 surgically resected gallbladders and cultures of human gallbladder epithelial cells (HGECs) and gallbladder carcinoma cell line (TGBC2TKB), we examined carcinogenesis with respect to cellular senescence. Among 15 cases of PBM in which carcinoma was found in 4 cases, nonneoplastic gallbladder mucosa showed diffuse papillary hyperplasia (PHP). PHP was not found in gallbladders with cholecystolithiasis. Interestingly, PHP exhibited senescent features such as expression of p16(INK4A) and low cell proliferative activity. In contrast, EZH2, a polycomb group protein, was overexpressed in intraepithelial neoplasm and carcinoma in gallbladders with cholecystolithiasis. In PBM, EZH2 was expressed only in carcinoma foci but not in PHP. Cultured HGECs treated with lysolecithin, the level of which is elevated in gallbladder bile of PBM, showed increased expression of p16(INK4A) and senescence-associated beta-galactosidase. Conversely, enforced overexpression of EZH2 in senescent HGECs reduced p16(INK4A) expression. A knockdown of EZH2 in cultured TGBC2TKB cells increased p16(INK4a) expression. In conclusion, PHP in PBM may act as a barrier to malignant transformation for decades. EZH2 may be responsible for the escape from cellular senescence followed by malignant transformation in the gallbladder of PBM.

Intestinal metaplasia in gallbladder correlates with high amylase levels in bile in patients with a morphologically normal pancreaticobiliary duct

We reported previously that intestinal metaplasia in the gallbladder is strongly associated with expression of caudal-related homeobox transcription factor Cdx2. It has been documented that occult pancreatobiliary reflux, even in the absence of pancreaticobiliary maljunction, is associated with elevated risk of biliary malignancy. We ascertained the correlation between intestinal metaplasia in the gallbladder and occult pancreatobiliary reflux. In 196 patients with a normal pancreaticobiliary ductal arrangement who had undergone laparoscopic cholecystectomy, we performed intraoperative cholangiography and measured amylase levels in bile sampled from the gallbladder. The cutoff value for high cystic amylase was defined as a biliary amylase level higher than the normal upper limit of serum amylase (215 IU/L). We also retrospectively reviewed the cholecystectomized tissue specimens to investigate the presence of intestinal metaplasia and expression of Cdx2. Then, we explored the relationship between intestinal metaplasia in the gallbladder and occult choledocho-pancreatic reflux. Intestinal metaplasia was found in 16.8% (33/196) of the gallbladders. The prevalence of choledocho-pancreatic reflux revealed by intraoperative cholangiography was not significantly different between cases with intestinal metaplasia (5/33, 15.2%) and those without (25/163, 15.3%; P = .81). However, in cases with intestinal metaplasia, the rate of high cystic amylase (13/33, 39.4%) was significantly higher compared with cases without intestinal metaplasia (26/163, 16.0%, P = .005). In conclusion, intestinal metaplasia in the gallbladder is significantly correlated with high amylase levels in bile in patients with a morphologically normal pancreaticobiliary ductal arrangement.

Pancreatobiliary reflux resulting in pancreatic ascites and choleperitoneum after gallbladder perforation

A 65-year-old man with chronic hepatitis C and no history of alcohol abuse was admitted to our liver unit for the recent development of massive ascites and presumed hepatorenal syndrome. In the preceding two weeks, he had received medical treatment for acute pancreatitis and cholecystitis. Abdominal paracentesis demonstrated a cloudy, orange peritoneal fluid, with total protein concentration 3.6 g/dl, serum-ascites albumin gradient 1.0 g/dl, and ratios of ascites-serum bilirubin and amylase approximately 8:1. Diagnostic imaging demonstrated no pancreatic pseudocysts. Ten days later, at laparotomy, acalculous perforation of the gallbladder was identified. After cholecystectomy, amylase concentration in the ascitic fluid dropped within a few days to 40% of serum values; ascites disappeared within a few weeks. We conclude that in the presence of a perforated gallbladder, pancreatobiliary reflux was responsible for this unusual combination of choleperitoneum and pancreatic ascites, which we propose to call pancreatobiliary ascites.