p53 gene mutations and overexpression of p53 product in cancerous and noncancerous biliary epithelium in patients with pancreaticobiliary maljunction

Choledochocele with hyperplastic epithelium in a patient who developed severe acute pancreatitis and underwent subtotal stomach-preserving pancreatoduodenectomy: a case report

Choledochocele is defined as a congenital dilatation of the distal intramural part of the common bile duct protruding into the wall of the descending duodenum, typically without pancreaticobiliary maljunction. However, some cases present with a similar pathophysiology to pancreaticobiliary maljunction, including reciprocal reflux of pancreatic juices and bile, leading to protein plugs, pancreatitis, and biliary tract carcinogenesis. Choledochocele is relatively rare and its anatomy, physiology, pathology, and clinical features are thus not well known. We describe a patient with choledochocele who suffered from repeated severe acute pancreatitis and underwent subtotal stomach-preserving pancreatoduodenectomy, in whom the pathological findings of choledochocele showed hyperplasia.

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.

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.

Risk of carcinogenesis in the biliary epithelium of children with congenital biliary dilatation through epigenetic and genetic regulation

PURPOSES

Congenital biliary dilatation (CBD), defined as pancreaticobiliary maljunction (PBM) with biliary dilatation, is a high risk factor for biliary tract cancer (BTC). KRAS and p53 mutations reportedly affect this process, but the mechanisms are unclear, as is the likelihood of BTC later in life in children with CBD. We investigated potential carcinogenetic pathways in children with CBD compared with adults.

METHODS

The subjects of this study were nine children with CBD and 13 adults with PBM (10 dilated, 3 non-dilated) without BTC who underwent extrahepatic bile duct resections, as well as four control patients who underwent pancreaticoduodenectomy for non-biliary cancer. We evaluated expressions of Ki-67, KRAS, p53, histone deacetylase (HDAC) and activation-induced cytidine deaminase (AID) in the biliary tract epithelium immunohistochemically.

RESULTS

The Ki-67 labeling index (LI) and expressions of KRAS, p53, HDAC, and AID in the gallbladder epithelium were significantly higher or tended to be higher in both the children with CBD and the adults with PBM than in the controls.

CONCLUSIONS

BTC may develop later in children with CBD and in adults with PBM, via HDAC and AID expression and through epigenetic and genetic regulation.

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.

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.

Biliary carcinogenesis in pancreaticobiliary maljunction

Pancreaticobiliary maljunction (PBM) is a congenital malformation in which the pancreatic and bile ducts join anatomically outside the duodenal wall. Because of the excessive length of the common channel in PBM, sphincter action does not directly affect the pancreaticobiliary junction, which allows pancreatic juice to reflux into the biliary tract. According to the results of a nationwide survey, bile duct and gallbladder cancers were found in 6.9 and 13.4 % of adult patients with congenital biliary dilatation, respectively, and in 3.1 and 37.4 % of those with PBM without biliary dilatation, respectively. Biliary tract cancers develop about 15-20 years earlier in patients with PBM than in individuals without PBM; they sometimes develop as double cancers. Carcinogenesis is strongly associated with stasis of bile intermingled with refluxed pancreatic juice. Epithelial cells in the biliary tract of PBM patients are under constant attack from activated pancreatic enzymes, increased secondary bile acids, or other mutagens. This can result in hyperplastic change with increased cell proliferation activity, and in turn, oncogene and/or tumor suppressor gene mutations in the epithelia, leading to the biliary tract carcinogenesis. The carcinogenesis of biliary tract cancer accompanying PBM is considered to involve a hyperplasia-dysplasia-carcinoma sequence induced by chronic inflammation caused by the reflux of pancreatic juice into the biliary tract, which differs from the adenoma-carcinoma sequence or the de novo carcinogenesis associated with biliary tract cancers in the population without PBM. Patients with a relatively long common channel have a similar, albeit slightly lower, risk for gallbladder cancer compared with PBM patients.

Well-differentiated endocrine carcinoma originating from the bile duct in association with a congenital choledochal cyst

We encountered a rare case of a well-differentiated endocrine carcinoma originating from the bile duct in association with a congenital choledochal cyst (CCC). The patient is a 28-year-old woman referred to our clinic for pruritus. Laboratory data showed mild elevation of serum hepatobiliary enzymes. Computed tomography and magnetic resonance imaging demonstrated pancreatobiliary maljunction and a Todani type IV-A CCC from the inferior bile duct to the bilateral intrahepatic bile ducts. A solid tumor was detected in the middle portion of the common bile duct. Pancreatoduodenectomy and total extrahepatic bile duct resection was performed. Based on pathologic and immunohistochemical examinations, a diagnosis of well-differentiated endocrine carcinoma was made according to the World Health Organization criteria. To our knowledge, this is the third report of a neuroendocrine tumor originating from the bile duct in association with a CCC.

Curative resection of hilar cholangiocarcinoma in a 25-year-old woman: report of a case

A 25-year-old woman was referred to our hospital with persistent upper abdominal pain. Preoperative imaging studies revealed a hilar bile duct stricture with portal venous encasement, and the patient underwent curative resection involving extended left hepatectomy and segmental portal vein resection. The pathological findings demonstrated a well-differentiated tubular adenocarcinoma of the bile duct with regional lymph node metastasis (stage IIIB according to the UICC TNM classification), as well as the overexpression of p53 proteins and the K-ras gene mutation in tumor cells. The patient has shown no evidence of recurrence in the 10 months since the operation. Although there are several reports of relatively young adults with cholangiocarcinoma, the majority of such patients demonstrate either an anomalous arrangement of the pancreaticobiliary duct system or primary sclerosing cholangitis. The absence of any morphological abnormalities in this patient's biliary system implicates de novo carcinogenesis as the most likely cause of the cholangiocarcinoma.

Modern diagnostic approaches to cholangiocarcinoma

BACKGROUND

Cholangiocarcinoma is a very aggressive tumor with poor survival. Therefore, early diagnosis and surgical resection are of paramount importance. Its diagnosis is difficult because access to the tumor is not easy. Biopsy is possible only for intrahepatic cholangiocarcinoma, which accounts for 10% of cases. Routine brush cytology from endoscopic retrograde cholangiopancreatography (ERCP) has a high specificity of 100% but unfortunately a low sensitivity of 30%. In this review we briefly describe new diagnostic techniques applicable to ERCP brush cytology specimens and targeting the genetic background of the disease, in particular fluorescence in situ hybridization (FISH) and digital image analysis (DIA).

DATA SOURCES

The PubMed database up to 2011 was used for the retrieval of relevant articles. The search terms FISH, fluorescence in situ hybridization, DIA, digital image analysis and cholangiocarcinoma were used. Both original and review articles were used.

RESULTS

FISH identifies cells with chromosomal abnormalities, mainly numerical aberrations, using a mixture of fluorescence-labeled probes. FISH offers a higher sensitivity than routine cytology, retaining a high level of specificity. The DIA criterion for malignancy is demonstration of aneuploidy. This technique increases the sensitivity to 40%, but the specificity remains low. Preliminary data from application to other tumors suggest that combination of FISH and DIA may be of further benefit.

CONCLUSIONS

The new techniques offer a significantly enhanced diagnostic efficacy in the evaluation of ERCP brush specimens. Apart from contributing to a more timely diagnosis, their wider application to cholangiocarcinoma may also facilitate the genetic study of the disease and add to our understanding of oncogenesis at the molecular level, with the prospect of identifying targets for novel therapeutic interventions.

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.

Metachronous Carcinomas of the Biliary Tract in a Patient Treated Three Times with Curative Surgery

We here report on a case of metachronous multicentric carcinomas of the biliary tract treated 3 times with curative surgery over 23 years. A 28-year-old woman underwent cholecystectomy because of papillary carcinoma of the gallbladder. After 17 years, 3 carcinomas developed in the biliary tract: intrahepatic cholangiocarcinoma of the left liver, common bile duct carcinoma, and remnant cystic duct carcinoma. They were successfully removed via left hepatectomy combined with pylorus-preserving pancreatoduodenectomy. Furthermore, another intrahepatic cholangiocarcinoma developed 6 years after the second surgery, which was removed again via partial resection of the posterior segment of the liver. Histological findings of carcinomas represented various grades of cell differentiation. No predisposition toward carcinogenesis was found, since neither pancreaticobiliary maljunction nor primary sclerosing cholangitis was present, and the overexpression of cyclooxygenase-2 was negative in all resected specimens. Close monitoring for recurrence is warranted for early detection of metachronous carcinoma that might be effectively treated with repeated resection.

p53 gene mutation and p53 protein overexpression in a patient with simultaneous double cancer of the gallbladder and bile duct associated with pancreaticobiliary maljunction

Pancreaticobiliary maljunction (PBM) is associated with the occurrence of biliary cancer due to pancreatobiliary reflux. We present a case of simultaneous double cancer of the gallbladder and bile duct. A 77-year-old woman who had jaundice, intra- and extra-hepatic biliary ductal dilatation and a space-occupying lesion in the gallbladder and lower bile duct underwent pancreatoduodenectomy. The gallbladder cancer showed papillary carcinoma without mutation of the K-ras gene and with p53 non-sense mutation of CCA (Pro) to CA (Stop) on codon 301 in exon 8. The bile duct cancer revealed a well-differentiated adenocarcinoma without mutation of the K-ras gene and with p53 miss-sense mutation of GTG (Val) to GAG (Glu) on codon 272 in exon 8. There were no mutations of either the K-ras or p53 gene in non-cancerous epithelia. In contrast, only the mucosa of the common channel had p53 protein accumulation and high cell proliferation activity. Therefore, the genetic pathway might be the same in both the gallbladder and bile duct cancer, and a high potential for carcinogenesis might be present in the epithelium of the common channel in patients with PBM.

Secretin-stimulating MRCP in patients with pancreatobiliary maljunction and occult pancreatobiliary reflux: direct demonstration of pancreatobiliary reflux

We propose the hypothesis that the enlargement of the common bile duct (CBD) or gallbladder (GB) that is occasionally demonstrated on magnetic resonance cholangiopancreatography (MRCP) after secretin stimulation is caused by pancreatobiliary reflux. Recently, occult pancreatobiliary reflux (OPR) has been demonstrated in patients without morphological pancreatobiliary maljunction (MPBM). The aim of this study was to evaluate the efficacy of secretin-stimulating MRCP (SMRCP) in the diagnosis of pancreatobiliary reflux. The study included 14 patients with MPBM and 32 patients with a normal pancreatobiliary junction. OPR was evaluated by bile collection and diagnosed in seven of the 32 patients. All the patients underwent SMRCP; the related findings were considered positive when enlargement of the CBD or GB was observed. Positive findings on SMRCP were observed in all MPBM patients. In the patients with normal pancreatobiliary junction, there was significant difference between the mean amylase levels in the patients with positive and negative SMRCP findings (mean, 4,755.7 and 29.7 IU/l). The sensitivity and specificity of SMRCP for diagnosing OPR was 85.7% and 68.0%, respectively. SMRCP provides a non invasive method for excluding PBR and can identify patients who could benefit from bile duct sampling to diagnose OPR.

Histological study of gallbladder and bile duct epithelia in patients with anomalous arrangement of the pancreaticobiliary ductal system: comparison between those with and without a dilated common bile duct

BACKGROUND

We histologically evaluated the epithelia of the gallbladder (GB) and bile duct (BD) in patients with anomalous arrangement of the pancreaticobiliary ductal system (AAPB), with regard to the shape of the common BD (CBD).

METHODS

The GB and BD were studied histologically using surgical materials from 44 patients with AAPB: 27 with a dilated CBD (D-type) and 17 with a nondilated CBD (N-type).

RESULTS

GB cancer and BD cancer were found in 11.1% and 3.7% of D-type and 17.6% and 0% of N-type respectively. Hyperplastic epithelium and atypical epithelium of the GB were frequently seen in both D-type (46%, 46%) and N-type (82%, 70%), while such epithelia of the BD were only seen in D-type (10%, 35%). The Ki67 labeling index of the nonneoplastic epithelium of the GB was high in both D-type (13.0%) and N-type (9.7%), though that of the BD was high in D-type (12.5%) but low in N-type (1.8%). The prevalences of pyloric gland metaplasia, intestinal metaplasia, and p53 protein overexpression of the nonneoplastic epithelium did not show any significant differences between D-type and N-type.

CONCLUSIONS

It is suggested that the BD epithelium of N-type probably has a lower potential for developing malignancy than that of D-type, while the GB epithelia of both D-type and N-type have a high potential for developing malignancy. This might support the selection of simple cholecystectomy as the treatment of choice in AAPB patients of N-type, although further investigation of the BD epithelium is required in a larger number of such patients.

Expression of GalNAc-T3 and its relationships with clinicopathological factors in 61 extrahepatic bile duct carcinomas analyzed using stepwise sections - special reference to its association with lymph node metastases-

Extrahepatic bile duct carcinomas (EBDCs) still result in an unfavorable prognostic outcome, and little is known about their biological aggressiveness. Recently, UDP-N-acetyl-alpha-D-galactosamine:polypeptide N-acetylgalactosaminyl transferase-3 (GalNAc-T3) was reported to be associated with differentiation and malignant potential of human carcinomas. Here, we investigated 61 EBDCs for their detailed clinicopathological features and GalNAc-T3 expression by immunohistochemistry, and then evaluated the relationships between the clinicopathological features and GalNAc-T3 expression patterns. Most of the EBDCs were massively invasive tumors with frequent vascular or perineural invasion and lymph node metastases. GalNAc-T3 expression was detected in all 61 EBDCs, and the expression patterns could be classified into granular and diffuse types. All four noninvasive or minimally invasive EBDCs were the granular type. Among the 58 minimally or massively invasive EBDCs, the GalNAc-T3 expression pattern at the luminal surface was the granular type in 38 cases (66%) and diffuse type in 20 cases (34%), while the expression pattern at the invasive front was the granular type in 26 cases (45%) and diffuse type in 32 cases (55%). Among the 38 cases with granular-type expression at the luminal surface, 26 cases (68%) remained the granular type and 12 cases (32%) became the diffuse type at the invasive front. All 20 cases with diffuse-type expression at the luminal surface remained the diffuse type at the invasive front. Diffuse-type GalNAc-T3 expression at the invasive front was significantly associated with lymph node metastasis (P<0.05). There were no significant correlations between the GalNAc-T3 expression patterns and other clinicopathological factors, including tumor differentiation, depth of invasion or overall survival. In conclusion, EBDCs alter their GalNAc-T3 expression pattern during tumor growth, and the difference in the GalNAc-T3 expression pattern may be associated with lymph node metastasis. Clinically, preoperative evaluation of GalNAc-T3 expression is considered to be useful for decisions regarding operative procedures.

Double cancer of gall bladder and bile duct not associated with anomalous junction of the pancreaticobiliary duct system

BACKGROUND

Simultaneous double cancers of the biliary tract are rare. Most of them are thought to be associated with pancreaticobiliary maljunction (PBM); however, the characteristics of tumours without PBM are still unclear.

METHODS

Histology, immunoreactivity with carcinoembryonic antigen, carbohydrate antigen 19-9 and p53 and mutations in the K-ras gene were examined in tumours resected from cases of simultaneous double cancers of the biliary tract.

RESULTS

Four cases of simultaneous double cancers of the biliary tract were identified among 108 patients with biliary tract cancer (3.7%). None of the four cases associated with PBM, and the results of histological, immunohistochemical and genetic examinations differed between the bile duct and gall bladder cancers in each case.

CONCLUSION

Even when they do not associate with PBM, double cancers in the biliary tract are more likely to be the result of multicentric development.

Biliary tract cancers: molecular profiling as a tool for treatment decisions. A literature review

Biliary tract cancer is a quite rare disease; despite recent significant advances in imaging modalities, most of the patients have advanced disease at presentation thus making radical surgery not feasible. Many different chemotherapeutic regimens have been investigated in small uncontrolled studies, with generally disappointing results. We extensively reviewed the literature on this topic trying to give an explanation to chemoresistance in this setting of patients and considering the molecular profiling as a tool for treatment decision. This review is divided in two parts, in the first one we illustrated chemotherapy results and possible mechanisms of resistance. In the second part we analysed the new molecular targets developing an hypothesis about the future therapeutics perspectives.

Expression of cyclooxygenase-2 is associated with p53 accumulation in premalignant and malignant gallbladder lesions

AIM: To examine the relationship between cyclooxygenase-2 (COX-2) overexpression and p53 accumulation in gallbladder carcinoma and its precursor lesions.

METHODS: Sixty-eight gallbladder tissue samples comprising 14 cases of normal gallblader epithelium, 27 cases of dysplasia (11 low-grade dysplasia and 16 high-grade dysplasia) and 27 adenocarcinomas were evaluated by immunohistochemistry for COX-2 expression and p53 accumulation. The relationship among COX-2 expression, p53 accumulation and clinicopathological characteristics was analysed.

RESULTS: COX-2 was expressed in 14.3% of normal gallbladder epithelium, 70.3% of dysplastic epitehlium, and 59.2% of adenocarcinomas. When divided into low- and high-grade dysplasia, COX-2 was positive in 5 (45.4%) cases of low-grade and 14 (87.5%) of high-grade dysplasia (P = 0.019). Accumulation of p53 was detected in 5 (31.2%) cases of high-grade dysplasia and in 13 (48.1%) of carcinomas. No p53 accumulation was found in normal epithelium or low-grade dysplasia. COX-2 overexpression was observed in 17 of 18 (94.4%) cases with p53-accumulation in comparison with 20 (40.0%) out of 50 cases without p53 accumulation (P < 0.001).

CONCLUSION: The significant differences in COX-2 expression among normal epithelium, low-grade dysplasia and high-grade dysplasia suggest that overexpression of COX-2 enzyme is an early event in gallbladder carcinogenensis. Furthermore, since accumulation of p53 correlates with COX-2 expression, COX-2 overexpression observed in gallbladder high-grade dysplasia and carcinoma might be partly due to the dysfunction of p53.

K-ras, p53 mutations, and microsatellite instability (MSI) in gallbladder cancer

Despite the considerable progress in understanding the molecular pathology of carcinogenesis, the genetic mechanisms underlying the development and progression of gallbladder cancer (GC) are poorly understood. The survival of GC patients is generally poor. Therefore, it is very useful to define valuable prognostic factors. The most extensively studied oncogenes in gallbladder carcinogenesis are ras, commonly mutated in neoplasms of the gastrointestinal tract. K-ras oncogene is altered in a subset of gallbladder patients and mainly in those having anomalous junction of the pancreaticobiliary tract. Most of the studies of genetic abnormalities in GC have focused on p53 gene. p53 mutation/overexpression and/or LOH is present in more than 50% of gallbladder carcinomas, suggesting an important role in their pathogenesis. However, these results have not any predictive value yet. Moreover, the involvement of an alternative molecular pathway, that of microsatellite instability (MSI), is found in a limited group of GC patients. Additional research is necessary to establish its possible relation to defects of the mismatch repair (MMR) system and its proposed prognostic significance. Further elucidation of the molecular events specific to GC will help to identify novel molecular targets for the diagnosis and clinical management of the patients.

High-level microsatellite instability is not involved in gallbladder carcinogenesis

The molecular alterations involved in the pathogenesis of gallbladder cancer are not yet well defined. Our aim was to determine the microsatellite status of gallbladder carcinomas and its possible correlation with alterations in K-ras and p53 genes as well as the clinicopathological characteristics of these tumors. A group of 37 gallbladder carcinomas was analyzed for alterations in a proposed panel of mononucleotide and dinucleotide markers of microsatellite instability. Somatic frameshift mutations at repeated sequences in the coding regions of TGF-betaRII, Bax, hMSH3, hMSH6 were also examined. The findings were correlated with the presence of K-ras and p53 alterations, and tumors' clinicopathological features. Microsatellite instability and/or LOH was observed in 9 gallbladder carcinomas. Cases showing microsatellite instability displayed alterations only in dinucleotide markers and were classified as MSI-L carcinomas. A subset of gallbladder carcinomas is characterized by low-level instability, based on the analysis of the above mentioned panel of markers. The pathway of microsatellite instability seems to play a minor role in the pathogenesis of gallbladder cancer.

Pathologic changes in the non-carcinomatous epithelium of the gallbladder in patients with a relatively long common channel

BACKGROUND

Except for pancreaticobiliary maljunction, the relationship between a relatively long common channel and gallbladder carcinoma is unknown.

METHODS

For purposes of this study, a high confluence of pancreaticobiliary ducts was defined as a common channel that is 6 mm or greater in length, together with occlusion of the communication between the pancreatic and bile ducts during sphincter contraction. Pancreaticobiliary maljunction and high confluence of the pancreaticobiliary ducts were detected in 69 (2.1%) and 54 (1.6%), respectively, of 3300 consecutive patients who underwent ERCP. Proliferation activity and genetic alteration were examined in the non-carcinomatous epithelium of the gallbladder in patients with these two radiographic findings at ERCP.

RESULTS

The Ki-67 labeling index in the epithelium in cases of a high confluence of the pancreaticobiliary ducts and pancreaticobiliary maljunction without biliary dilatation was significantly greater than that in cases of gallbladder carcinoma without these anomalies (p < 0.01). Overexpression of p53 and K-ras mutations were detected in, respectively, 22.2% and 27.8% of cases of a high confluence of pancreaticobiliary ducts.

CONCLUSIONS

A relatively long common channel may be an important risk factor for the development of gallbladder carcinoma. Vigilance for the development of gallbladder carcinoma is indicated in patients with a relatively long common channel, in addition to those with pancreaticobiliary maljunction.

Association of anomalous pancreaticobiliary ductal junction with gallbladder carcinoma in Chinese patients: an ERCP study

BACKGROUND

Anomalous pancreaticobiliary ductal junction, a rare congenital anomaly, is associated with various biliary and pancreatic diseases. The aim of this study was to determine the frequency of anomalous pancreaticobiliary ductal junction in Chinese patients with gallbladder cancer.

METHODS

One thousand eight hundred seventy-six patients underwent ERCP between April 2000 and September 2001 with biliary and pancreatic duct opacification in 1082. Among the latter patients, those with proven gallbladder carcinoma were identified. Anomalous pancreaticobiliary ductal junction was defined as a common channel greater than 15 mm in length or a contractile segment totally distal to the union of the biliary and pancreatic ducts. When the common bile duct appeared to join the main pancreatic duct, the anomalous pancreaticobiliary ductal junction was denoted as B-P subtype; if the main pancreatic duct appeared to join the common bile duct, it was denoted P-B subtype.

RESULTS

Fifty-four patients had gallbladder carcinoma, 7 of whom (3 men, 4 women) had anomalous pancreaticobiliary ductal junction (P-B subtype 6, B-P subtype 1). The mean (SD) length of the common channel was 21.0 mm (11.2 mm) with a range of 12 to 45 mm. One patient had early cystic dilation of bile duct. Three other patients had anomalous pancreaticobiliary ductal junction; 1 had an associated choledochal cyst and 2 a normal biliary tree. The overall frequency of anomalous pancreaticobiliary ductal junction was 0.9% (10/1082 cases). The frequency of anomalous pancreaticobiliary ductal junction was significantly higher in patients with gallbladder carcinoma (p < 0.001; OR, 50.7; 95% CI [12.7, 202.3]).

CONCLUSIONS

Anomalous pancreaticobiliary ductal junction is strongly associated with gallbladder cancer among Chinese patients.

Pancreaticobiliary maljunction: pathophysiological and clinical aspects and the impact on biliary carcinogenesis

BACKGROUND

Pancreaticobiliary maljunction (PBM) is frequently associated with congenital choledochal cyst (CCBD), but differs in embryonic cause and clinical features. It is thought to develop as a misarrangement of the embryonic connections in the pancreaticobiliary ductal system, with the terminal bile duct joined to one of the ducts of the ventral pancreas. Clinical aspects are intermittent abdominal pain, relapsing acute pancreatitis, jaundice, cholangitis, and gallbladder cancer. In patients with PBM and CCBD, primary bile duct stones, acute cholangitis, and bile duct cancer are considered to result from cholestasis, regurgitation of pancreatic juice, and reciprocal reflux of bile and pancreatic juice. The mixture of bile and pancreatic juice due to recipocal reflex very likely plays an important role in biliary carcinogenesis.

PATIENTS AND METHODS

We reviewed the pathophysiological and clinical aspects and biliary carcinogenesis in 250 PBM patients (169 with benign hepatobiliary and pancreatic disease, 81 with malignancy).

RESULTS

PBM patients show elevated cellular proliferation activity in the gallbladder epithelia. A number of oncogenes and tumor suppressor genes have been identified and implicated in carcinogenesis, particularly the K- ras oncogene and the p53 suppressor gene. Some K- ras mutations do not appear essential for hyperplasia but may be an early event in carcinogenesis. The p53 mutations are involved in carcinogenesis in the biliary epithelium in PBM patients.

Immunohistochemical detection of 8-hydroxy-2'-deoxyguanosine in gallbladder epithelium of patients with pancreaticobiliary maljunction

OBJECTIVES

Pancreaticobiliary maljunction, an anomalous union of the pancreatic duct with the common bile duct, is a risk factor for biliary carcinoma. We hypothesized that, in patients with pancreaticobiliary maljunction, persistent regurgitation of pancreatic juice into the biliary tract induces oxidative DNA damage. We assessed the expression of an oxidative DNA base-modified product, 8-hydroxy-2'-deoxyguanosine, in gallbladder epithelium.

DESIGN

Eleven noncancerous gallbladders from patients with pancreaticobiliary maljunction, 12 gallbladder carcinomas from patients without pancreaticobiliary maljunction and 14 noncancerous gallbladders from patients without pancreaticobiliary maljunction (control) were studied.

METHODS

Immunohistochemistry was performed for 4-hydroxy-2-nonenal-modified protein (as a marker for lipid peroxidation), 8-hydroxy-2'-deoxyguanosine and p53 gene product.

RESULTS

Stronger cytoplasmic staining of 4-hydroxy-2-nonenal-modified protein was observed in the gallbladder epithelium from patients with pancreaticobiliary maljunction than in epithelium from gallbladder cancer patients or from control subjects with normal gallbladders. Clear, strong nuclear staining of 8-hydroxy-2'-deoxyguanosine was observed in the gallbladder epithelial cells from patients with pancreaticobiliary maljunction. Densitometric quantitation revealed significantly higher expression of 8-hydroxy-2'-deoxyguanosine in gallbladder epithelial cells from patients with pancreaticobiliary maljunction (index 27.3 +/- 3.1) than in cells from patients with gallbladder carcinoma (11.4 +/- 1.5; P < 0.05) or from control subjects with normal gallbladder (6.4 +/- 1.0; P < 0.05). Positivity of p53 was 27% in gallbladder epithelium associated with pancreaticobiliary maljunction, 75% in gallbladder carcinoma epithelium and 0% in control epithelium.

CONCLUSIONS

These results suggest that reactive oxygen species are produced in the gallbladder of patients with pancreaticobiliary maljunction and that oxidative DNA injury is related to carcinogenesis in these patients.

Genes and viruses in hepatobiliary neoplasia

Hepatobiliary neoplasms comprise a significant portion of the worldwide cancer burden. Advances in basic science research have led to rapid progress in our understanding of the molecular events responsible for these dreaded diseases. The genetic changes associated with hepatocellular carcinoma (HCC) have received the most attention. Aflatoxin B1 exposure leads to mutations in the p53 tumor suppressor gene, most commonly a transversion in codon 249 that leads to a substitution of serine for arginine in the p53 protein. Numerous other tumor suppressor genes, oncogenes, and tumor gene pathways are altered in HCC. Hepatitis B virus (HBV) infection is strongly associated with HCC. HBV may cause HCC either directly via the HBV X protein, or indirectly by causing liver inflammation and cirrhosis. Hepatitis C virus (HCV) infection is also associated with HCC. Recent evidence suggests that the HCV core protein may play a role in hepatocarcinogenesis. Several inherited metabolic diseases are associated with HCC. It is likely that these diseases cause HCC indirectly by causing cirrhosis. The molecular pathogenesis of cholangiocarcinoma and gallbladder cancer has not been well defined. However, multiple tumor suppressor genes and oncogenes, including p53 and K-ras, are altered in these tumors. Further molecular characterization of hepatobiliary tumors may lead to earlier diagnosis, better staging, improved treatment planning, and the development of more effective therapies.