Mimics of cholangiocarcinoma: spectrum of disease

Adult bile duct strictures: role of MR imaging and MR cholangiopancreatography in characterization

Bile duct strictures in adults are secondary to a wide spectrum of benign and malignant pathologic conditions. Benign causes of bile duct strictures include iatrogenic causes, acute or chronic pancreatitis, choledocholithiasis, primary sclerosing cholangitis, IgG4-related sclerosing cholangitis, liver transplantation, recurrent pyogenic cholangitis, Mirizzi syndrome, acquired immunodeficiency syndrome cholangiopathy, and sphincter of Oddi dysfunction. Malignant causes include cholangiocarcinoma, pancreatic adenocarcinoma, and periampullary carcinomas. Rare causes include biliary inflammatory pseudotumor, gallbladder carcinoma, hepatocellular carcinoma, metastases to bile ducts, and extrinsic bile duct compression secondary to periportal or peripancreatic lymphadenopathy. Contrast material-enhanced magnetic resonance (MR) imaging with MR cholangiopancreatography is extremely helpful in the noninvasive evaluation of patients with obstructive jaundice, an obstructive pattern of liver function, or incidentally detected biliary duct dilatation. Some of these conditions may show characteristic findings at MR imaging-MR cholangiopancreatography that help in making a definitive diagnosis. Although endoscopic retrograde cholangiopancreatography with tissue biopsy or surgery is needed for the definitive diagnosis of many of these strictures, certain MR imaging characteristics of the narrowed segment (eg, thickened wall, long-segment involvement, asymmetry, indistinct outer margin, luminal irregularity, hyperenhancement relative to the liver parenchyma) may favor a malignant cause. Awareness of the various causes of bile duct strictures in adults and familiarity with their appearances at MR imaging-MR cholangiopancreatography are important for accurate diagnosis and optimal patient management.

Segmental cholangiectasia clinically worrisome for cholangiocarcinoma: comparison with recurrent pyogenic cholangitis

The aim of this study was to review the clinical, radiographic, and pathologic features of cases of benign segmental cholangiectasia in non-Asian US patients with clinical concern for cholangiocarcinoma and compare these features with cases of recurrent pyogenic cholangitis (RPC) in Asian patients. A total of 10 non-Asian US patients with benign segmental cholangiectasia were included in this study. Nine of them underwent partial hepatic resection due to cholangiographic findings of segmental cholangiectasia with mural thickening and/or proximal biliary stricture. One was found to have markedly dilated and thickened intrahepatic bile ducts at the time of autopsy. Clinical and radiographic findings were reviewed. Elastin stains and immunostains for immunoglobulin G4, cluster of differentiation (CD1a), and Langerin were performed. Six comparison cases of RPC in Asian US patients were also examined. Histologic examination of resection specimens revealed markedly dilated large intrahepatic bile ducts with variable degrees of mural fibrosis, periductal gland hyperplasia, inflammation, and liver parenchymal atrophy. These changes were not associated with a ductular reaction. There was no evidence of biliary dysplasia or biliary cirrhosis in any cases. No gross or microscopic feature definitively separated the Asian from non-Asian patients. The etiology of this disorder in non-Asian US patients is unclear. It does not appear to represent a localized variant of Caroli disease or primary sclerosing cholangitis. The high degree of similarity shared by these cases and classic RPC suggests a common pathogenic mechanism, although the pathologic features tend to be less well developed in the cases from the non-Asian US patients.

Bile duct tumors

Bile duct tumors are benign or malignant lesions which may be associated to risk factors or potentially malignant lesions. They constitute an heterogenous entities group with a different biological behavior and prognosis according to location and growth pattern. We revise the role of the radiologist in order to detect, characterize and stage these tumors, specially the importance of their classification when deciding an appropriate management and treatment.

Metastatic breast cancer mimicking a hilar cholangiocarcinoma: case report and review of the literature

BACKGROUND/AIMS

Breast cancer is the most common tumor in women and the first cause of death for malignancy in the female population. Bile ducts are not among the common sites of metastasis from breast cancer; few cases of obstructive jaundice due to metastatic breast cancer have been described in the literature and they mostly resulted from widespread liver metastases that eventually involved the bile ducts. We report an exceptional case of metastatic infiltration of the extrahepatic bile ducts in absence of liver metastases.

CASE PRESENTATION

A 56-year-old woman who had undergone a right mastectomy 13 years earlier due to infiltrating ductal breast cancer and had remained tumor free, presented at a follow-up examination with obstructive jaundice.Imaging (computed tomography, magnetic resonance and endoscopic retrograde cholangiopancreatography) scans showed features that were suggestive of a primary tumor of the extrahepatic bile duct. At surgery, the intraoperative findings were also those of a tumor of the bile duct, however, an histological examination showed no evidence of malignancy in the mucosa, but did shown an infiltration of the external wall from adenocarcinoma. Immunohistochemistry analysis demonstrated that the tumor was metastatic breast cancer.

CONCLUSIONS

Indeterminate stenosis of the extrahepatic bile ducts should be examined with suspicion in women with a history of breast cancer, and bile duct metastases are to be considered among the possible diagnoses. A differential diagnosis from cholangiocarcinoma is of paramount importance and mainly relies on pathology.

Bile proteome in health and disease

The study of bile proteins could improve the understanding of physiological processes involved in the regulation of the hepato-biliary system. Researchers have tried for years to investigate the bile proteome but, until recently, only a few tens of proteins were known. The advent of proteomics, availing of large-scale analytical devices paired with potent bioinformatic resources, lately allowed the identification of thousands of proteins in bile. Nevertheless, the knowledge of their role in the hepato-biliary system still represents almost a "blank page in the book of physiology." In this review, we first guide the reader through the historical phases of the analysis of bile protein content, emphasizing the recent progresses achieved through the use of proteomic techniques. Thereafter, we deeply explore the involvement of bile proteins in health and disease, with a particular focus on the discovery of biomarkers for biliary tract malignancies.

MRI of cholangiocarcinoma

Cholangiocarcinomas are the second most common primary hepatobiliary tumors after hepatocellular carcinomas. They can be categorized either based on their location (intrahepatic/perihilar/extrahepatic distal) or their growth characteristics (mass-forming/periductal-infiltrating/intraductal) because they exhibit varied presentations and outcomes based on their location and or pattern of growth. The increased risk of cholangiocarcinoma in PSC necessitates close surveillance of these patients by means of imaging and laboratory measures; and because currently surgical resection is the only effective treatment for cholangiocarcinoma, the need for accurate pre-operative staging and assessment of resectability has emphasized the role of high quality imaging in management. Today magnetic resonance imaging (MRI) is the modality of choice for detection, pre-operative staging and surveillance of cholangiocarcinoma.

Bile analysis using high-throughput FTIR spectroscopy for the diagnosis of malignant biliary strictures: a pilot study in 57 patients

This study aimed at determining whether FTIR spectroscopy is able to distinguish bile samples from patients with and without malignant biliary strictures. Bile samples were collected in 19 patients with malignant biliary strictures and 38 with benign biliary diseases during endoscopic procedures. FTIR spectra were acquired on dried drops of whole bile, aqueous and organic phases obtained after lipid extraction. Data were analyzed by principal component analysis and by the support vector machine classification using a leave-n-out cross validation procedure. This was applied to the whole set of spectra and the mean and median spectra of each patient. By leaving one patient out, the classifier allowed discriminating patients with and without malignant biliary strictures with a sensitivity between 82% and 95% and a specificity between 85% and 100%. Using a randomized leave-n -out cross-validation with n = 2, 5 and 10 patients, the sensitivity decreased slightly by about 5 to 10% while the specificity remained stable, suggesting the robustness of the classifier. FTIR spectroscopy combined with chemometrics therefore shows potential to differentiate bile from patients with and without malignant biliary strictures. Although promising, the results of this pilot study cannot be generalized and needs to be confirmed in a larger population.

Magnetic resonance evaluations of biliary malignancy and condition at high-risk for biliary malignancy: Current status

Tumors of the biliary tree are relatively rare; but their incidence is rising worldwide. There are several known risk factors for bile duct cancers, and these are seem to be associated with chronic inflammation of the biliary epithelium. Herein, 2 risk factors have been discussed, primary sclerosing cholangitis and reflux of pancreatic juice into the bile duct, as seen in such as an abnormal union of the pancreatic-biliary junction because magnetic resonance imaging (MRI) is used widely and effectively in the diagnosis of these diseases. When biliary disease is suspected, MRI can often help differentiate between benignity and malignancy, stage tumors, select surgical candidates and guide surgical planning. MRI has many advantages over other modalities. Therefore, MRI is a reliable noninvasive imaging tool for diagnosis and pre-surgical evaluation of bile duct tumors. Nowadays remarkable technical advances in magnetic resonance technology have expanded the clinical applications of MRI in case of biliary diseases. In this article, it is also discussed how recent developments in MRI contributes to the diagnosis of the bile duct cancer and the evaluation of patients with risk factors affecting bile duct cancer.

Imaging biliary strictures--a pictorial review

The diagnosis of biliary diseases may be delayed or missed because of an unpredictable clinical course and presentation. Some biliary diseases carry the risk of morbidity and mortality and are difficult to treat. The purpose of this article is to revisit the various causes and the appearances of biliary strictures on different imaging modalities and to emphasize the role of magnetic resonance imaging (MRI) with magnetic resonance cholangiopancreatography (MRCP) in their evaluation compared with endoscopic retrograde cholangiopancreatography. MRI with MRCP is advantageous to endoscopic retrograde cholangiopancreatography for being a 1-stop shop to provide biliary, soft tissue, and vascular information that is helpful for planning intervention or surgery. Thus it serves as a superb imaging modality for the evaluation of biliary strictures.

Biliary manifestations of systemic diseases

Patients with a variety of systemic diseases may present with clinical indications of biliary tract disorders. This article describes a group of systemic conditions associated with bile duct abnormalities and the role of endoscopic therapy in their diagnosis and management.

Comparison of concomitant and subsequent cholangiocarcinomas associated with hepatolithiasis: Clinical implications

AIM: To compare the outcomes of concomitant cholangiocarcinoma (C-CCA) and subsequent cholangiocarcinoma (S-CCA) associated with hepatolithiasis.

METHODS: From December 1987 to December 2007, 276 patients underwent hepatic resection for hepatolithiasis in Changhua Christian Hospital. Sixty-five patients were excluded due to incomplete medical records and the remaining 211 patients constituted our study population base. Ten patients were diagnosed with C-CCA based on the preoperative biopsy or postoperative pathology. During the follow-up period, 12 patients developed S-CCA. The diagnosis of S-CCA was made by image-guided biopsy or by pathology if surgical intervention was carried out. Patient charts were reviewed to collect clinical information. Parameters such as CCA incidence, interval from operation to CCA diagnosis, interval from CCA diagnosis to disease-related death, follow-up time, and mortality rate were calculated for both the C-CCA and S-CCA groups. The outcomes of the C-CCA and S-CCA groups were mathematically compared and analysed.

RESULTS: Our study demonstrates the clinical implications and the survival outcomes of C-CCA and S-CCA. Among the patients with unilateral hepatolithiasis, the incidence rates of C-CCA and S-CCA were fairly similar (4.8% vs 4.5%, respectively, P = 0.906). However, for the patients with bilateral hepatolithiasis, the incidence rate of S-CCA (12.2%) was higher than that of C-CCA (4.7%), although the sample size was limited and the difference between two groups was not statistically significant (P = 0.211). The average follow-up time was 56 mo for the C-CCA group and 71 mo for the S-CCA group. Regard to the average time intervals from operation to CCA diagnosis, S-CCA was diagnosed after 67 mo from the initial hepatectomy. The average time intervals from the diagnoses of CCA to disease-related death was 41 mo for the C-CCA group and 4 mo for the S-CCA group, this difference approached statistical significance (P = 0.075). Regarding the rates of overall and disease-related mortality, the C-CCA group had significantly lower overall mortality (70% vs 100%, P = 0.041) and disease-related mortality (60% vs 100%, P = 0.015) than the S-CCA group. For the survival outcomes of two groups, the Kaplan-Meier curves corresponding to each group also demonstrated better survival outcomes for the C-CCA group (log rank P = 0.005). In the C-CCA group, three patients were still alive at the time of data analysis, all of them had free surgical margins and did not have pathologically proven lymph node metastasis at the time of the initial hepatectomy. In the S-CCA group, only one patient had chance to undergo a second hepatectomy, and all 12 S-CCA patients had died at the time of data analysis.

CONCLUSION: C-CCA has better outcomes than S-CCA. The first hepatectomy is crucial because most patients with recurrent CCA or S-CCA are not eligible for repeated surgical intervention.

A study of mifepristone/IFN-γ-induced apoptosis of human cholangiocarcinoma cell line FRH-0201 in vitro

OBJECTIVE

To investigate the effects of mifepristone, a progesterone receptor (PR) antagonist, through the proliferation of human cholangiocarcinoma cell line FRH-0201 in vitro and the possible mechanisms involved.

METHODS

A two-step addition of poly-HRP anti-mouse immunoglobulin G detection system was used to detect the expression of PR in FRH-0201 cells. After treatments with various concentrations of mifepristone (10, 20, 40, 80, 160, and 320 μmol/L) at various time intervals (24, 48, and 72 hours), the rate of cell inhibition, the rate of cell apoptosis, and the expression of bax/bcl-2/Fas were analyzed with tetrazolium blue (MTT) assay, flow cytometry, reverse transcription polymerase chain reaction and Western blotting. The effect of mifepristone and mifepristone combined with interferon (IFN)-γ-inducing apoptosis on the cells was observed.

RESULTS

Mifepristone remarkably inhibited the proliferation of FRH-0201 cells, which was revealed by MTT assay in a dose- and time-dependent manner. The inhibitory rate gradually increased following the increase of the dosage of mifepristone from a low dosage (10 μmol/L) to a high dosage (320 μmol/L) at different time intervals. Flow cytometry analysis showed mifepristone increased the rate of the FRH-0201 cell-line apoptosis. Notably, the rate of apoptosis increased markedly when the cells were pretreated with IFN-γ and then treated with mifepristone. In addition, mifepristone obviously upregulated bax and Fas expression and downregulated bcl-2 expression.

CONCLUSION

Mifepristone effectively inhibited the growth of PR-positive human cholangiocarcinoma cell line FRH-0201 in vitro through multiple mechanisms. Mifepristone combined with IFN-γ might therefore induce the apoptosis of the cell line, which is possibly a beneficial clinical scheme for patients suffering from cholangiocarcinoma.

Detection of IGF2BP3, HOXB7, and NEK2 mRNA expression in brush cytology specimens as a new diagnostic tool in patients with biliary strictures

Introduction

It is a challenging task to distinguish between benign and malignant lesions in patients with biliary strictures. Here we analyze whether determination of target gene mRNA levels in intraductal brush cytology specimens may be used to improve the diagnosis of bile duct carcinoma.

Materials and Methods

Brush cytology specimens from 119 patients with biliary strictures (malignant: n = 72; benign: n = 47) were analyzed in a retrospective cohort study. mRNA of IGF-II mRNA-binding protein 3 (IGF2BP3), homeobox B7 (HOXB7), Forkhead box M1 (FOXM1), kinesin family member 2C (KIF2C) and serine/threonine kinase NEK2 was determined by semi-quantitative RT-PCR using the ΔCt method.

Results

IGF2BP3 (p<0.0001), HOXB7 (p<0.0001), and NEK2 (p<0.0001) mRNA expression levels were significantly increased in patients with cholangiocarcinoma or pancreatic cancer. Median ΔCt values differed by 3.5 cycles (IGF2BP3), 2.8 cycles (HOXB7) and 1.3 cycles (NEK2) corresponding to 11-fold, 7-fold and 2.5-fold increased mRNA levels in malignant versus benign samples. Sensitivity to detect biliary cancer was 76.4% for IGF2BP3 (80.9% specificity); 72.2% for HOXB7 (78.7% specificity) and 65.3% for NEK2 (72.3% specificity), whereas routine cytology reached only 43.1% sensitivity (85.4% specificity). Diagnostic precision was further improved, when all three molecular markers were assessed in combination (77.8% sensitivity, 87.2% specificity) and achieved 87.5% sensitivity and 87.2% specificity when molecular markers were combined with routine cytology.

Conclusions

Our data suggest that measuring IGF2BP3, HOXB7 and NEK2 mRNA levels by RT-PCR in addition to cytology has the potential to improve detection of malignant biliary disorders from brush cytology specimens.

Klatskin-like lesions

Hilar cholangiocarcinoma, also known as Klatskin tumour, is the commonest type of cholangiocarcinoma. It poses unique problems in the diagnosis and management because of its anatomical location. Curative surgery in the form of major hepatic resection entails significant morbidity. About 5-15% of specimens resected for presumed Klatskin tumour prove not to be cholangiocarcinomas. There are a number of inflammatory, infective, vascular, and other pathologies, which have overlapping clinical and radiological features with a Klatskin tumour, leading to misinterpretation. This paper aims to summarise the features of such Klatskin-like lesions that have been reported in surgical literature.

Inflammatory myofibroblastic tumour of liver masquerading as hilar cholangiocarcinoma

There is a wide variety of inflammatory and benign neoplastic disorders of the biliary system that mimic cholangiocarcinoma in terms of clinical manifestations and imaging findings. Inflammatory myofibroblastic tumour of the bilary tract is one such condition, which is extremely rare but benign. Like cholangiocarcinoma this condition presents as painless progressive obstructive jaundice and it is often difficult to differentiate between the two prior to laparotomy, with the usual investigative modalities. Diagnosis is usually established by the characteristic histopathology findings in biopsy specimen. Newer diagnostic modalities directed at obtaining preoperative biopsy of the lesion appear promising in differentiating benign from malignant biliary lesions, but their routine use is yet to become standardised. Until then, awareness of doctors about the existence of such benign entities might prompt a less aggressive treatment approach while dealing with atypical hilar lesions of liver.

Magnetic resonance imaging of biliary tumors

This article presents current magnetic resonance imaging techniques for the diagnosis of biliary tumors. It emphasizes the need for a comprehensive protocol, combining imaging sequences of the liver parenchyma and soft tissues with magnetic resonance cholangiopancreatography and magnetic resonance angiography to detect and stage biliary malignancies. Imaging characteristics that may indicate a specific diagnosis are discussed. The potential role of diffusion-weighted imaging in diagnosing the cause of biliary obstruction and detecting unsuspected nodal disease and peritoneal seeding is emphasized and illustrated.

Primary hepatoid carcinoma of the biliary tree: a radiologic mimicker of Klatskin-type tumor

Hepatoid carcinomas are a group of neoplasms with features resembling hepatocellular carcinomas. Although extremely rare, more cases have been noted to arise from various organs within the last decade. Differentiating these tumors when located in the biliary tree from cholangiocarcinoma is not only a radiologic challenge but also critical, because treatment modalities and operative strategies are dependent on the exact nature of the tumor. We report a unique case in the literature of a 67-year-old Caucasian female who presented with obstructive jaundice due to an obstructing mass seen at the common hepatic duct on imaging with no preceding history of cirrhosis and increased serum α-fetoprotein (AFP), in whom a differential diagnosis from cholangiocarcinoma in a non-cirrhotic liver was particularly difficult given the combination of tumor location and solitary nature. The radiologist may include ectopic hepatoid adenocarcinomas in the differential consideration of an obstructing tumor in the biliary tree especially in patients with increased serum AFP levels.

CT and MR findings in extramedullary haematopoiesis with biliary system encasement: a case report

Extramedullary haematopoiesis is the production of blood elements outside the bone marrow cavity. In our case computed tomography and magnetic resonance imaging revealed the presence of a rare localization of extramedullary haematopoiesis with encasement of the biliary system in a 59 years-old male Caucasian patient, with chronic myelofibrosis and hepatic failure's symptomatology. Computed tomography detected the presence of homogeneous hypodense tissue around intra-hepatic bile ducts with minimal contrast enhancement, strongly suggestive for extramedullary haematopoiesis. Magnetic resonance confirmed the presence of a solid tissue surrounding the biliary tree, showing late enhancement after gadolinium administration suggestive for non-active lesion of extramedullary haematopoiesis. Final diagnosis was established by percutaneous biopsy.

Lymphoplasmacytic sclerosing cholangitis: assessment of clinical, CT, and pathological findings

AIM

To assess the clinical, computed tomography (CT), and pathological findings in patients with lymphoplasmacytic sclerosing cholangitis.

MATERIALS AND METHODS

Fifteen consecutive patients (four women and 11 men, mean age 71 years) with lymphoplasmacytic sclerosing cholangitis and without the characteristic features of underlying disorders causing benign biliary strictures were retrospectively recruited. Two radiologists evaluated multiphase contrast-enhanced CT images acquired with 0.5 or 1-mm collimation. One pathologist performed all histological examinations, including IgG4 immunostaining.

RESULTS

The intrahepatic biliary ducts showed dilatation in all 15 patients, but only seven presented with jaundice. Although laboratory data were not available in all patients, serum gammaglobulin and IgG levels were elevated in five of six patients and six of eight patients, respectively. Anti-nuclear antibody was detected in three of six patients. The involved biliary ducts showed the following CT findings: involvement of the hilar biliary duct (14/15), a mean wall thickness of 4.9 mm, a smooth margin (10/15), a narrow but visible lumen (6/15), hyper-attenuation during the late arterial phase (9/15), homogeneous hyper-attenuation during the delayed phase (11/11), and no vascular invasion (14/15). Abnormal findings in the pancreas and urinary tract were detected in eight of 15 patients. In 13 patients with adequate specimens, moderate to severe lymphoplasmacytic infiltration associated with dense fibrosis was observed. Infiltration of IgG4-positive plasma cells was moderate or severe in nine patients and minimal or absent in four patients.

CONCLUSION

Lymphoplasmacytic sclerosing cholangitis exhibits relatively characteristic clinical and CT findings, although they are not sufficiently specific for differentiation from other biliary diseases.