CT Differentiation of cholangiocarcinoma from periductal fibrosis in patients with hepatolithiasis

Practice guidelines for managing extrahepatic biliary tract cancers

Backgrounds/Aims

Reported incidence of extrahepatic bile duct cancer is higher in Asians than in Western populations. Korea, in particular, is one of the countries with the highest incidence rates of extrahepatic bile duct cancer in the world. Although research and innovative therapeutic modalities for extrahepatic bile duct cancer are emerging, clinical guidelines are currently unavailable in Korea. The Korean Society of Hepato-Biliary-Pancreatic Surgery in collaboration with related societies (Korean Pancreatic and Biliary Surgery Society, Korean Society of Abdominal Radiology, Korean Society of Medical Oncology, Korean Society of Radiation Oncology, Korean Society of Pathologists, and Korean Society of Nuclear Medicine) decided to establish clinical guideline for extrahepatic bile duct cancer in June 2021.

Methods

Contents of the guidelines were developed through subgroup meetings for each key question and a preliminary draft was finalized through a Clinical Guidelines Committee workshop.

Results

In November 2021, the finalized draft was presented for public scrutiny during a formal hearing.

Conclusions

The extrahepatic guideline committee believed that this guideline could be helpful in the treatment of patients.

Cholangiocarcinoma imaging: from diagnosis to response assessment

Cholangiocarcinoma (CCA), a highly aggressive primary liver cancer arising from the bile duct epithelium, represents a substantial proportion of hepatobiliary malignancies, posing formidable challenges in diagnosis and treatment. Notably, the global incidence of intrahepatic CCA has seen a rise, necessitating a critical examination of diagnostic and management strategies, especially due to presence of close imaging mimics such as hepatocellular carcinoma (HCC) and combined hepatocellular carcinoma-cholangiocarcinoma (cHCC-CCA). Hence, it is imperative to understand the role of various imaging modalities such as ultrasound, computed tomography (CT), and magnetic resonance imaging (MRI), elucidating their strengths, and limitations in diagnostic precision and staging accuracy. Beyond conventional approaches, there is emerging significance of functional imaging tools including positron emission tomography (PET)-CT and diffusion-weighted (DW)-MRI, providing pivotal insights into diagnosis, therapeutic assessment, and prognostic evaluation. This comprehensive review explores the risk factors, classification, clinical features, and role of imaging in the holistic spectrum of diagnosis, staging, management, and restaging for CCA, hence serving as a valuable resource for radiologists evaluating CCA.

Prediction of Multiple Serum Tumor Markers in Hepatolithiasis Complicated with Intrahepatic Cholangiocarcinoma

Objective

To evaluate the predictive value of multiple serum tumor markers in hepatolithiasis complicated with intrahepatic cholangiocarcinoma (hepatolithiasis-associated cholangiocarcinoma, HL-CCA).

Methods

From January 2010 to December 2020, three hundred eighty-five hepatolithiasis patients in Zhoukou Central Hospital were retrospectively analyzed, among them thirty patients complicated with intrahepatic cholangiocarcinoma. The levels of serum AFP, CA125, CA19-9, CA242, and CEA in hepatolithiasis or HL-CCA were measured. Receiver operating characteristic (ROC) curves were used to evaluate the diagnostic effects of single or combined detection of the five tumor markers for HL-CCA.

Results

The level of AFP was insignificantly different between the hepatolithiasis and HL-CCA (P=0.730). CA125, CA19-9, CA242 and CEA were elevated in HL-CCA. The area under ROC curves (AUCs) of the single detection of serum CA125, CA19-9, CA242 and CEA were all more than 0.5. The maximum AUC occurred in CA19-9. The AUC of AFP was slightly higher than 0.5, but the level of serum AFP was insignificantly different between hepatolithiasis and HL-CCA. The single detection of AFP was not of great significance to the differential diagnosis. The optimal cut-off values of CA125, CA19-9, CA242, and CEA were 104.09 kU/L, 383.28 U/mL, 152.56 kU/L, 6.29 ng/mL. The diagnostic effect of CA19-9 was the highest one for differential diagnosis between hepatolithiasis and HL-CCA. With reference to CA19-9 >383.28 U/mL, the sensitivity and specificity of the single detection were 80.00% and 82.61% respectively, and the AUC was 0.883. The diagnostic effect of CEA was secondary toward CA19-9. With reference to CEA >6.29 ng/mL, the sensitivity and specificity of the single detection were 66.67% and 83.76% respectively, and the AUC was 0.814.

Conclusion

Serum CA19-9 maybe the effective tumor marker in the diagnosis of HL-CCA, and measurement of combined serum tumor markers can help in the detection of HL-CCA.

Resection of extrahepatic bile ducts with partial hepatectomy for treating intra- and extrahepatic hepatolithiasis

Background

To evaluate the efficacy and safety of our new surgical procedures for primary intra- and extrahepatic hepatolithiasis. Hepatolithiasis is an intractable disease with frequent recurrences.

Methods

From 1996 to 2005, 142 patients with intrahepatic and/or extrahepatic hepatolithiasis treated with the conventional surgical methods were included as the control group, while 128 consecutive patients treated with new surgical methods from 2006 to 2015 were included as the observation group. The new surgical procedures included a comprehensive intraoperative exploration of the bile ducts, focusing on the structure and function of the hilar bile duct and duodenal papilla, exploration of the affected liver, and bile culture.

Results

The observation group had a significantly higher complete stone clearance rate than the control group (100% vs. 65.96%). The observation group had significantly lower incidences of cholangitis and bile duct stones, as well as a higher excellent and good long-term surgical efficacy rate (86.24% vs. 52.73%). Multivariate Cox analysis showed that the control group had a higher risk for fair + poor efficacy than the observation group (HR: 8.47).

Conclusions

Our new surgical procedures are safe and can provide a good long-term efficacy for treating primary hepatolithiasis intra- and extrahepatic hepatolithiasis.

The imbalance of biliary microflora in hepatolithiasis

BACKGROUND

The imbalance of microbial flora is thought to be associated with many diseases. However, the characteristics of the biliary microflora and its relation to in hepatolithiasis are unknown.

METHODS

This study included 40 patients with hepatolithiasis and 10 control patients. Bile samples were taken during hepatectomy surgeries and 16S rRNA sequencing was performed. The sequencing results were analyzed by operational taxonomic unit (OTU) clustering, species annotation and abundance analyses, sample complexity analyses, diversity analyses, and environmental factor correlation analyses.

RESULTS

There were significant differences in bile microflora between the hepatolithiasis group and the control group. We found that the abundance of microflora in the bile of patients with hepatolithiasis was relatively high (52.4% versus 40.2% and 42.1% versus 29.6%). The diversity of microflora in the bile of patients with hepatolithiasis decreased significantly (Shannon (P = 0.004), Observed species (P = 0.001), PD-whole-tree (P = 0.001)). These differences are mainly associated with Enterococcus(P＜0.001), Enterobacter(P = 0.003). In addition, we found that there were intra-group differences in hepatolithiasis, but the differences in the hepatolithiasis group were generally smaller than the differences in the non-hepatolithiasis group.

CONCLUSION

There is an imbalance of microflora in the bile duct of patients with hepatolithiasis. The imbalance of biliary flora may be associated with hepatolithiasis pathogenesis.

Cholangiocarcinoma: Part 1, Pathological and Morphological Subtypes, Spectrum of Imaging Appearances, Prognostic Factors and Staging

Cholangiocarcinoma (CC) is the most frequent malignant tumor of the biliary tract. The vast majority of cholangiocarcinomas are adenocarcinomas with a high proportion of fibrous stroma. Based on the macroscopic growth pattern, CC is classified as mass-forming, periductal infiltrating, or intraductal, with each type having its own characteristic imaging findings and prognostic outcome. The recently proposed pathological classification of cholangiocarcinoma into two types: perihilar large duct type and peripheral small duct and/or ductular type helps in better understanding of the morphology and the imaging appearances. Computed tomography (CT) and magnetic resonance imaging (MRI) remain the main tools of imaging. We aim to provide a comprehensive outline of the different subtypes and the rationale behind various imaging features of these subtypes. Cholangiocarcinoma is one of the more difficult tumors to treat and till date, surgery remains the only definitive curative treatment.

Modified percutaneous transhepatic papillary balloon dilation for patients with refractory hepatolithiasis

BACKGROUND

Some patients with hepatolithiasis cannot tolerate surgery due to severe cardiac or pulmonary comorbidities, or cannot be endoscopically treated because of altered gastrointestinal anatomies.

AIM

To propose a modified percutaneous transhepatic papillary balloon dilation procedure, and evaluate the clinical efficacy and safety of this modality.

METHODS

Data from 21 consecutive patients who underwent modified percutaneous transhepatic papillary balloon dilation with hepatolithiasis were retrospectively analyzed. Using auxiliary devices, intrahepatic bile duct stones were pushed into the common bile duct and expelled into the duodenum with an inflated balloon catheter. The outcomes recorded included success rate, procedure time, hospital stay, causes of failure, and procedure-related complications. Patients with possible long-term complications were followed up for 2 years.

RESULTS

Intrahepatic bile duct stones were successfully removed in 20 (95.23%) patients. Mean procedure time was 65.8 ± 5.3 min. Mean hospital stay was 10.7 ± 1.5 d. No pancreatitis, gastrointestinal, or biliary duct perforation was observed. All patients were followed up for 2 years, and there was no evidence of reflux cholangitis or calculi recurrence.

CONCLUSION

Modified percutaneous transhepatic papillary balloon dilation was feasible and safe with a small number of patients with hepatolithiasis, and may be a treatment option in patients with severe comorbidities or in patients in whom endoscopic procedure was not successful.

Peribiliary glands: development, dysfunction, related conditions and imaging findings

Peribiliary glands are minute structures that are distributed along the intrahepatic large bile ducts, extrahepatic bile duct, and cystic duct. These glands regulate many physiological functions, such as enzyme secretion. Pancreatic exocrine tissues and enzymes are often observed in peribiliary glands; thus, peribiliary glands are involved in enzyme secretion. As such, these glands can be affected by conditions such as IgG4-related sclerosing cholangitis based on commonalities with their pancreatic counterparts. Cystic changes in peribiliary glands can occur de novo, as part of a congenital syndrome, or secondary to insults such as alcoholic cirrhosis. Biliary tree stem/progenitor cells have recently been identified in peribiliary glands. These cells are involved in turnover and regeneration of biliary epithelia as well as in sclerosing reactions in some pathological conditions, such as primary sclerosing cholangitis and hepatolithiasis. Notably, hepatolithiasis is involved in mucin secretion by the peribiliary glands. Additionally, these cells are associated with the manifestation of several neoplasms, including intraductal papillary neoplasm, cystic micropapillary neoplasm, and cholangiocarcinoma. Normal peribiliary glands themselves are particularly small structures that cannot be recognized using any available imaging modalities; however, these glands are closely associated with several diseases, as mentioned above, which have typical imaging features. Therefore, knowledge of the basic pathophysiology of peribiliary glands is helpful for understanding biliary diseases associated with the peribiliary glands.

Early detection of intrahepatic cholangiocarcinoma

Cholangiocarcinoma (CC) is a malignant tumor which arises from the biliary epithelium and most cases represent adenocarcinoma. CC can be classified into intrahepatic CC (ICC), perihilar CC, and distal CC, based on the site of anatomic origin. The incidence of ICC is increasing in both Western and Eastern countries, while that of extrahepatic cholangiocarcinoma remains fairly stable. ICC infiltrates into adjacent nerves and lymphatic vessels, resulting in progressive disease with a poor prognosis; thus, early detection of ICC is critical for achieving better outcomes and providing better patient care. However, it is difficult for clinicians to detect an ICC, especially in its early stage. Different from hepatocellular carcinoma, the lack of surveillance system for the high-risk group of CC does not allow for a reliable screening examination. In this context, for early detection and diagnosis of ICC, radiologists need to know predisposing conditions that can lead to the development of ICC, such as chronic biliary or hepatic inflammation, primary sclerosing cholangitis, congenital biliary diseases, and other conditions. In this article, we discuss and illustrate the radiologic features of ICC with special attention to early disease stages and of predisposing conditions of ICC.

Outcomes following percutaneous treatment of biliary stones

BACKGROUND

The percutaneous approach (PA) for management of biliary stones (BS) with or without an underlying biliary stenosis is an option for patients in whom an endoscopic approach (EA) is not possible. The aim of this study was to evaluate the efficacy of a PA in patients with BS unsuitable for an EA.

METHODS

A retrospective review of a database was performed. Inclusion criteria included patients with benign disease, BS who had undergone a PA. The outcomes were technical success rate, short (≤90 days) and long-term (>90 days) efficacy and safety.

RESULTS

A total of 91 patients enrolled were divided into those with (n = 38) or without (n = 53) a biliary stenosis. A median of 5 (IQR:3-7) treatments/patient were performed. During a median follow-up of 23 months (IQR:3-52), the median time free from recurrence was 21 months (CI:14-29). In the long term, the PA was most efficacious in those patients without a biliary stenosis with long term success in 68% of patients as compared to 36% of patients with a biliary stenosis (p = 0.003).

CONCLUSION

A PA is an effective procedure with high initial success rate, however the coexistence of stenosis affects long-term efficacy, especially in patients with chronic biliary disease.

Multimodality imaging of intrahepatic cholangiocarcinoma

Intrahepatic cholangiocarcinomas account for approximately 20% of cases of cholangiocarcinomas. Three growth patterns or morphologic subtypes exist, including mass-forming, periductal-infiltrating, and intraductal-growth subtypes. Knowledge of these morphologic subtypes and their radiologic appearance aids in timely diagnosis, a key to optimizing patient outcomes. The morphologic variability of intrahepatic cholangiocarcinomas has a direct impact on the diagnostic sensitivity and specificity of various diagnostic imaging modalities, including ultrasound (US), computed tomography (CT), magnetic resonance imaging (MRI)/magnetic resonance cholangiopancreatography (MRCP), and positron emission tomography (PET). The following review emphasizes optimal imaging technique for each of these modalities and reviews the imaging appearance of each morphologic subtype of intrahepatic cholangiocarcinoma.

Intrahepatic cholangiocarcinoma: current perspectives

Intrahepatic cholangiocarcinoma (ICC) is the second most common malignancy arising from the liver. ICC makes up about 10% of all cholangiocarcinomas. It arises from the peripheral bile ducts within the liver parenchyma, proximal to the secondary biliary radicals. Histologically, the majority of ICCs are adenocarcinomas. Only a minority of patients (15%) present with resectable disease, with a median survival of less than 3 years. Multidisciplinary management of ICC is complicated by large differences in disease course for individual patients both across and within tumor stages. Risk models and nomograms have been developed to more accurately predict survival of individual patients based on clinical parameters. Predictive risk factors are necessary to improve patient selection for systemic treatments. Molecular differences between tumors, such as in the epidermal growth factor receptor status, are promising, but their clinical applicability should be validated. For patients with locally advanced disease, several treatment strategies are being evaluated. Both hepatic arterial infusion chemotherapy with floxuridine and yttrium-90 embolization aim to downstage locally advanced ICC. Selected patients have resectable disease after downstaging, and other patients might benefit because of postponing widespread dissemination and biliary obstruction.

Hepatolithiasis and intrahepatic cholangiocarcinoma: A review

Although the incidence of hepatolithiasis is decreasing as the pattern of gallstone disease changes in Asia, the prevalence of hepatolithiasis is persistently high, especially in Far Eastern countries. Hepatolithiasis is an established risk factor for cholangiocarcinoma (CCA), and chronic proliferative inflammation may be involved in biliary carcinogenesis and in inducing the upregulation of cell-proliferating factors. With the use of advanced imaging modalities, there has been much improvement in the management of hepatolithiasis and the diagnosis of hepatolithiasis-associated CCA (HL-CCA). However, there are many problems in managing the strictures in hepatolithiasis and differentiating them from infiltrating types of CCA. Surgical resection is recommended in cases of single lobe hepatolithiasis with atrophy, uncontrolled stricture, symptom duration of more than 10 years, and long history of biliary-enteric anastomosis. Even after resection, patients should be followed with caution for development of HL-CCA, because HL-CCA is an independent prognostic factor for survival. It is not yet clear whether hepatic resection can reduce the occurrence of subsequent HL-CCA. Furthermore, there are no consistent findings regarding prediction of subsequent HL-CCA in patients with hepatolithiasis. In the management of hepatolithiasis, important factors are the reduction of recurrence of cholangitis and suspicion of unrecognized HL-CCA.

Hilar cholangiocarcinoma with intratumoral calcification: A case report

This report describes a rare case of hilar cholangiocarcinoma with intratumoral calcification that mimicked hepatolithiasis. A 73-year-old man presented to a local hospital with a calcified lesion in the hepatic hilum. At first, hepatolithiasis was diagnosed, and he underwent endoscopic stone extraction via the trans-papillary route. This treatment strategy failed due to biliary stricture. He was referred to our hospital, and further examination suggested the existence of cholangiocarcinoma. He underwent left hepatectomy with caudate lobectomy and extrahepatic bile duct resection. Pathological examination revealed hilar cholangiocarcinoma with intratumoral calcification, while no stones were found. To the best of our knowledge, only one case of calcified hilar cholangiocarcinoma has been previously reported in the literature. Here, we report a rare case of calcified hilar cholangiocarcinoma and reveal its clinicopathologic features.

The role of diffusion-weighted MR imaging for differentiating benign from malignant bile duct strictures

OBJECTIVES

To assess the added value of diffusion-weighted imaging (DWI) to conventional magnetic resonance imaging (MRI) for differentiating benign from malignant bile duct strictures.

METHODS

Twenty-seven patients with a benign stricture and 42 patients with a malignant stricture who had undergone gadoxetic acid-enhanced MRI with DWI were enrolled. Qualitative (signal intensity, dynamic enhancement pattern) and quantitative (wall thickness and length) analyses were performed. Two observers independently reviewed a set of conventional MRI and a combined set of conventional MRI and DWI, and receiver operating characteristic (ROC) curve analysis was assessed.

RESULTS

Benign strictures showed isointensity (18.5-70.4 %) and a similar enhancement pattern (22.2 %) to that of normal bile duct more frequently than malignant strictures (0-40.5 % and 0 %) on conventional MRI (P < 0.05). Malignant strictures (90.5-92.9 %) showed hypervascularity on arterial and portal venous phase images more frequently than benign strictures (37.0-70.4 %) (P < 0.01) On DWI, all malignant strictures showed hyperintensity compared with benign cases (70.4 %) (P < 0.001). Malignant strictures were significantly thicker and longer than benign strictures (P < 0.001). The diagnostic performance of both observers improved significantly after additional review of DWI.

CONCLUSIONS

Adding DWI to conventional MRI is more helpful for differentiating benign from malignant bile duct strictures than conventional MRI alone.

KEY POINTS

• Accurate diagnosis and exclusion of benign strictures of bile duct are important. • Diffusion-weighted MRI helps to distinguish benign from malignant bile duct strictures. • DWI plus conventional MRI provides superior diagnostic accuracy to conventional MRI alone.

Diagnosis and treatment of cholangiocarcinoma in bile duct reoperation

AIM: To investigate the key points to the diagnosis and treatment of cholangiocarcinoma in bile duct reoperation.

METHODS: The clinical data for 26 patients who underwent bile duct reoperation and were finally diagnosed with cholangiocarcinoma from November 2006 to December 2011 were retrospectively analyzed.

RESULTS: There were 15 cases of intrahepatic cholangiocarcinoma and 11 cases of extrahepatic cholangiocarcinoma. For extrahepatic cholangiocarcinomas, 5 were located around the site of biliary-enteric anastomosis, and one was located within the choledochol cyst. Fifteen patients had cholelithiasis. Abdominal pain and obstructive jaundice were the most common symptom for intrahepatic cholangiocarcinomas and extrahepatic cholangiocarcinomas, respectively. Eight patients revealed atypical imaging findings, including inflammatory biliary strictures in 5 cases, atrophy of the liver in 2 cases and residual choledochol cyst in 1 case. Fourteen patients received en-bloc tumor resection.

CONCLUSION: Laboratory tests, imaging studies and frozen-section examinations should be combined to improve the diagnosis of cholangiocarcinomas in bile duct reoperation. The tumor and the residual lesion of the bile duct which causes the tumor should be removed completely.

Incidence of Cholangiocarcinoma with or without Previous Resection of Liver for Hepatolithiasis

BACKGROUND/AIMS

To investigate the incidence of cholangiocarcinoma in patients with hepatolithiasis with or without previous resection of liver.

METHODS

From 2002 to 2009, we retrospectively reviewed 117 patients who were diagnosed and treated for hepatolithiasis in Korea University Guro Hospital. Among the 117 patients, 55 patients who were lost during follow-up were excluded, and 62 patients were eligible for analysis. The hepatic resection group (n=25) included patients who underwent left hemihepatectomy (n=2); left lateral segmentectomy (n=10); left lobectomy (n=9); right lobectomy (n=3); or wedge resection (n=1). The nonhepatic resection group (n=37) included transhepatic cholangiographic lithotomy and endoscopic retrograde cholangiopancreatography-treated patients. The mean follow-up period was 47 months.

RESULTS

The incidence of cholangiocarcinoma while patients were followed for hepatolithiasis was 12.9% (8/62) (hepatic resection group, three cases [12%] vs nonhepatic resection group, five cases [13.5%]; p=1.000). The mean follow-up period was 53 months (47±11 months) until the diagnosis of cholangiocarcinoma.

CONCLUSIONS

There was no difference in the incidence of cholangiocarcinoma according to previous liver resections. Patients with hepatolithiasis should be carefully followed up for detection of cholangiocarcinoma even after a previous liver resection.

Classification and management of hepatolithiasis: A high-volume, single-center's experience

Hepatolithiasis is endemic to East Asia, but immigration from the region means that this rare but emerging disease will pose a therapeutic challenge to doctors in the West as well. Curative management of hepatolithiasis is difficult since its etiology has not been fully elucidated. Hepatectomy is the best approach to treating hepatolithiasis. Here, we propose a novel classification of hepatolithiasis and describe features of each type. We then relate our experience with various forms of hepatectomy to treat different types of hepatolithiasis. Surgery should be indicated for all cases of hepatolithiasis. The proposed classification will help to determine surgical strategies. Better selection of which patients should undergo a hepatectomy will lead to better outcomes.

A rare grade III symptomatic Tsunoda class III left lobe hepatolithiasis in a North American woman

A 44-year-old Caucasian woman without any identified predisposing factors, presented to her local emergency room with multiple episodes of recurrent ascending cholangitis. She underwent a laparoscopic cholecystectomy several years prior to her admission to the hospital for parenteral antibiotic therapy and she had no personal or family history of hypercholesterolaemia. Transferred to a tertiary hospital for surgical therapy, she underwent a left hepatic resection for a chronically infected left lobe hepatolithiasis (HL) conditioning atrophy of the parenchyma due to obstruction of the biliary tree by multiple large cholesterol stones. HL is a very rare condition in Western countries and its aetiology and predisposing factors are still unclear. We present her symptomatology, diagnostic and therapeutic management and discuss the epidemiology and risk factors of HL, that is, a common condition in South East Asia while exceptional in Caucasian patients who have not travelled in high-prevalence regions.

Diffusion-weighted imaging of biliopancreatic disorders: Correlation with conventional magnetic resonance imaging

Diffusion-weighted magnetic resonance imaging (DWI) is a well established method for the evaluation of intracranial diseases, such as acute stroke. DWI for extracranial application is more difficult due to physiological motion artifacts and the heterogeneous composition of the organs. However, thanks to the newer technical development of DWI, DWI has become increasingly used over the past few years in extracranial organs including the abdomen and pelvis. Most previous studies of DWI have been limited to the evaluation of diffuse parenchymal abnormalities and focal lesions in abdominal organs, whereas there are few studies about DWI for the evaluation of the biliopancreatic tract. Although further studies are needed to determine its performance in evaluating bile duct, gallbladder and pancreas diseases, DWI has potential in the assessment of the functional information on the biliopancreatic tract concerning the status of tissue cellularity, because increased cellularity is associated with impeded diffusion, as indicated by a reduction in the apparent diffusion coefficient. The detection of malignant lesions and their differentiation from benign tumor-like lesions in the biliopancreatic tract could be improved using DWI in conjunction with findings obtained with conventional magnetic resonance cholagiopancreatography. Additionally, DWI can be useful for the assessment of the biliopancreatic tract in patients with renal impairment because contrast-enhanced computed tomography or magnetic resonance scans should be avoided in these patients.

Focal intrahepatic strictures: a review of diagnosis and management

INTRODUCTION

Focal intrahepatic strictures are becoming more common owing to more prevalent and accurate cross-sectional imaging. However, data relating to their management are lacking. The purpose of the present review was to synthesize the current evidence regarding these lesions and to formulate a strategy for diagnosis and management.

METHODS

A literature search of relevant terms was performed using Medline. References of papers were subsequently searched to obtain older literature.

RESULTS

Focal intrahepatic strictures involve segmental hepatic ducts and/or left and right main hepatic ducts during their intrahepatic course. Most patients are asymptomatic while the minority present with vague abdominal pain or recurrent sepsis and only rarely with jaundice. Investigations used to distinguish benign from malignant aetiologies include blood tests (CEA, Ca19.9), imaging studies [ultrasonography (US), computed tomography (CT), magnetic resonance cholangiopancreatography (MRCP) and fluorodeoxyglucose-positron emission tomography (FDG-PET)], endoscopic modalities [endoscopic retrograde cholangiopancreatography (ERCP)/endoscopic ultrasound (EUS)/cholangioscopy] and tissue sampling (brush cytology/biopsy).

CONCLUSIONS

A focal intrahepatic stricture requires thorough investigation to exclude malignancy even in patients with a history of biliary surgery, hepatolithiasis or parasitic infection. If during the investigative process a diagnosis or suspicion of malignancy is demonstrated then surgical resection should be performed. If all diagnostic modalities suggest a benign aetiology, then cholangioscopy with targeted biopsies should be performed.

Characterization of mesothelioma and tissues present in contrast-enhanced thoracic CT scans

PURPOSE

The purpose of this study was to characterize the Hounsfield unit (HU) distributions of mesothelioma and other tissues present in contrast-enhanced thoracic CT scans, to compare the HU distributions of mesothelioma, muscle, and liver by scanner and reconstruction filter/kernel combination, and to assess interpatient HU distribution variability.

METHODS

The database consisted of 28 contrast-enhanced thoracic CT scans from different patients. For each scan, regions of interest were manually outlined within each of 13 tissues, including mesothelioma. For each tissue, the empirical percentiles in HU values were calculated along with the interpatient variability. The HU distributions of select tissues were compared across three different scanner and reconstruction filter/kernel combinations.

RESULTS

The HU distributions of blood-containing tissues demonstrated substantial overlap, as did the HU distributions of pleural effusion, mesothelioma, muscle, and liver. The HU distribution of fat had the least overlap with the other tissues. Fat and muscle had the lowest interpatient HU variability and the narrowest HU distributions, while blood-containing tissues had the highest interpatient HU variability. A soft-tissue reconstruction filter/kernel yielded the narrowest HU distribution, and fat with artifact had the widest HU distribution.

CONCLUSIONS

Characterization of tissues in CT scans enhances the understanding of those tissues' HU distributions. Due to their overlapping HU distributions and close spatial proximity to one another, separating pleural effusion, mesothelioma, muscle, and liver from one another is a difficult task based on HU value thresholding alone. The results illustrate the wide distributions and large variability that exist for tissues present in clinical thoracic CT scans.

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.

Varying appearances of cholangiocarcinoma: radiologic-pathologic correlation

Intrahepatic cholangiocarcinoma is the second most common primary hepatic tumor. Various risk factors have been reported for intrahepatic cholangiocarcinoma, and the radiologic and pathologic findings of this disease entity may differ depending on the underlying risk factors. Intrahepatic cholangiocarcinoma can be classified into three types on the basis of gross morphologic features: mass-forming (the most common), periductal infiltrating, and intraductal growth. At computed tomography (CT), mass-forming intrahepatic cholangiocarcinoma usually appears as a homogeneous low-attenuation mass with irregular peripheral enhancement and can be accompanied by capsular retraction, satellite nodules, and peripheral intrahepatic duct dilatation. Periductal infiltrating cholangiocarcinoma is characterized by growth along the dilated or narrowed bile duct without mass formation. At CT and magnetic resonance imaging, diffuse periductal thickening and increased enhancement can be seen with a dilated or irregularly narrowed intrahepatic duct. Intraductal cholangiocarcinoma may manifest with various imaging patterns, including diffuse and marked ductectasia either with or without a grossly visible papillary mass, an intraductal polypoid mass within localized ductal dilatation, intraductal castlike lesions within a mildly dilated duct, and a focal stricture-like lesion with mild proximal ductal dilatation. Awareness of the underlying risk factors and morphologic characteristics of intrahepatic cholangiocarcinoma is important for accurate diagnosis and for differentiation from other hepatic tumorous and nontumorous lesions.

Intrahepatic cholangiocarcinoma associated with intrahepatic duct stones

OBJECTIVE

It has been well established that the long-term prognosis of intrahepatic duct stones (IHDS) is complicated by the late development of biliary cirrhosis with associated intrahepatic cholangiocarcinoma (IHCC). Despite recent improvements in imaging studies, accurate preoperative diagnosis of IHCC is difficult. Therefore, we attempted to elucidate the clinical features of patients with IHDS with IHCC.

METHODS

We reviewed 80 patients with IHDS and divided them into two groups. The DS group included 72 patients who had only IHDS. The second group was defined as the CC group and included eight patients who had IHDS and IHCC. For diagnosis of IHDS and confirmation of coexisting IHCC, patients underwent various radiological evaluations and additional laboratory tests, such as serum carbohydrate antigen 19-9 (CA 19-9).

RESULTS

There was no significant difference in the symptoms and stone characteristics between the two groups. For the CC group, liver resection was performed in four patients. Three patients underwent curative resection, but only one of these patients was alive at 36 months without recurrence.

CONCLUSION

IHCC with IHDS was difficult to diagnose in the early phase. Therefore, while performing diagnostic studies and surgery for IHDS, one should always consider the possibility of coexisting cholangiocarcinoma.

Surgical management of hepatolithiasis

BACKGROUND

Globalization and intercontinental migration have not just changed the socioeconomic status of regions, but have also altered disease dynamics across the globe. Hepatolithiasis, although still rare, is becoming increasingly evident in the West because of immigration from the Asia-Pacific region, where the disease prevails in endemic proportions. Such rare but emerging diseases pose a therapeutic challenge to doctors.

METHODS

Here, we briefly introduce the topic of hepatolithiasis and describe features of intrahepatic stones, the aetiology of hepatolithiasis and the symptoms and sequelae of the condition. We then provide a comprehensive review of the various management modalities currently in use to treat hepatolithiasis.

CONCLUSIONS

In our opinion, and as is evident from the literature, surgery remains the definitive treatment for hepatolithiasis. However, non-surgical procedures such as cholangiography, although limited in their therapeutic capabilities, play a vital role in diagnosis and preoperative evaluation.

Detection of biliary duct narrowing and choledocholithiasis: accuracy of portal venous phase multidetector CT

PURPOSE

To retrospectively evaluate the sensitivity and specificity of 64-detector computed tomography (CT) in the portal venous phase by using transverse images and both multiplanar and minimum intensity reformations for the detection of biliary duct narrowing and choledocholithiasis, with magnetic resonance cholangiopancreatography (MRCP) or endoscopic retrograde cholangiopancreatography (ERCP) as the reference standard.

MATERIALS AND METHODS

Approval from institutional review board was obtained for this HIPAA-compliant retrospective study; informed consent was waived. The study included all patients (42 men, 52 women; mean age, 61 years) who underwent abdominal 64-detector CT within 2 months of MRCP and/or ERCP. All patients underwent portal venous phase intravenous contrast material-enhanced abdominal CT. Sixty-one patients underwent MRCP and 54 patients underwent ERCP (21 patients underwent both). Two radiologists, blinded to the reference standard, independently evaluated the CT images, including multiplanar and minimum intensity reformations, for biliary duct narrowing and choledocholithiasis. Standard of reference examinations were used to calculate sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV).

RESULTS

Twenty-three (24%) of 94 patients had a biliary duct narrowing at reference examinations. For detecting biliary duct narrowing, observer 1 had a sensitivity of 78.2%, specificity of 100%, PPV of 100%, and NPV of 93.4% and observer 2 had a sensitivity of 69.6%, specificity of 100%, PPV of 100%, and NPV of 91.0%. In 18 (19%) of 94 patients, choledocholithiasis was detected at reference examinations. For detecting choledocholithiasis, observer 1 had a sensitivity of 77.8%, specificity of 96.1%, PPV of 82.4%, and NPV of 94.8% and observer 2 had a sensitivity of 72.2%, specificity of 96.1%, PPV of 81.2%, and NPV of 93.6%.

CONCLUSION

Portal venous phase multidetector CT images are highly specific and moderately sensitive for the detection of biliary duct narrowing and choledocholithiasis.

Diagnosis of cholangiocarcinoma

Cholangiocarcinoma is suspected based on signs of biliary obstruction, abnormal liver function tests, elevated tumor markers (carbohydrate antigen 19-9 and carcinoembryonic antigen), and ultrasonography showing a bile stricture or a mass, especially in intrahepatic cholangiocarcinoma. Magnetic resonance imaging (MRI) or computed tomography (CT) is performed for the diagnosis and staging of cholangiocarcinomas. However, differentiation of an intraductal cholangiocarcinoma from a hypovascular metastasis is limited at imaging. Therefore, reasonable exclusion of an extrahepatic primary tumor should be performed. Differentiating between benign and malignant bile duct stricture is also difficult, except when metastases are observed. The sensitivity of fluorodeoxyglucose positron emission tomography is limited in small, infiltrative, and mucinous cholangiocarcinomas. When the diagnosis of a biliary stenosis remains indeterminate at MRI or CT, endoscopic imaging (endoscopic or intraductal ultrasound, cholangioscopy, or optical coherence tomography) and tissue sampling should be carried out. Tissue sampling has a high specificity for diagnosing malignant biliary strictures, but sensitivity is low. The diagnosis of cholangiocarcinoma is particularly challenging in patients with primary sclerosing cholangitis. These patients should be followed with yearly tumor markers, CT, or MRI. In the case of dominant stricture, histological or cytological confirmation of cholangiocarcinoma should be obtained. More studies are needed to compare the accuracy of the various imaging methods, especially the new intraductal methods, and the imaging features of malignancy should be standardized.

Contrast-enhanced MRI combined with MR cholangiopancreatography for the evaluation of patients with biliary strictures: differentiation of malignant from benign bile duct strictures

PURPOSE

To determine imaging criteria for the combined use of contrast-enhanced (CE)-MRI and MR cholangiopancreatography (MRCP) to differentiate malignant from benign biliary strictures.

MATERIALS AND METHODS

A total of 44 patients with biliary stricture who had undergone unenhanced, MRCP, and dynamic MRI were identified from radiological and surgical databases. Two radiologists analyzed MR features for asymmetry, luminal irregularity, abrupt narrowing, outer margin, signal intensity (SI) on T2-weighted (T2W) images, and hyperenhancement relative to liver parenchyma during portal phase. The wall thickness and length of the narrowed segment were measured. MR findings relevant as predictors were identified using a Chi-square or Fisher's exact test and the odds ratio (OR).

RESULTS

The presence of hyperenhancement relative to liver parenchyma, length > 12 mm, wall thickness > 3 mm, indistinct outer margin, luminal irregularity, and asymmetry of strictured bile duct were significant factors for malignancy (P < 0.05). Malignant strictures were significantly thicker (5.0 +/- 2.0 mm) and longer (27.0 +/- 13.6 mm) than benign strictures. When any three or more of these six criteria were used in combination, we could identify 100% of malignant strictures and 87.0% of benign strictures.

CONCLUSION

The combined use of CE-MRI and MRCP helped to define the criteria for differentiating malignant from benign biliary strictures in our data.