Multiple cells of origin in cholangiocarcinoma underlie biological, epidemiological and clinical heterogeneity

Hepatic Nuclear Receptors in Cholestasis-to-Cholangiocarcinoma Pathology

Cholestasis, characterized by impaired bile flow, is associated with an increased risk of cholangiocarcinoma (CCA), a malignancy originating from the biliary epithelium and hepatocytes. Hepatic nuclear receptors (NRs) are pivotal in regulating bile acid and metabolic homeostasis, and their dysregulation is implicated in cholestatic liver diseases and the progression of liver cancer. This review elucidates the role of various hepatic NRs in the pathogenesis of cholestasis-to-CCA progression. We explore their impact on bile acid metabolism as well as their interactions with other signaling pathways implicated in CCA development. Additionally, we introduce available murine models of cholestasis/primary sclerosing cholangitis leading to CCA and discuss the clinical potential of targeting hepatic NRs as a promising approach for the prevention and treatment of cholestatic liver diseases and CCA. Understanding the complex interplay between hepatic NRs and cholestasis-to-CCA pathology holds promise for the development of novel preventive and therapeutic strategies for this devastating disease.

Expert Consensus on Pathological Diagnosis of Intrahepatic Cholangiocarcinoma (2022 version)

Intrahepatic cholangiocarcinoma (iCCA) can originate from the large bile duct group (segment bile ducts and area bile ducts), small bile duct group (septal bile ducts and interlobular bile ducts), and terminal bile duct group (bile ductules and canals of Hering) of the intrahepatic biliary tree, which can be histopathological corresponding to large duct type iCCA, small duct type iCCA and iCCA with ductal plate malformation pattern, and cholangiolocarcinoma, respectively. The challenge in pathological diagnosis of above subtypes of iCCA falls in the distinction of cellular morphologies, tissue structures, growth patterns, invasive behaviors, immunophenotypes, molecular mutations, and surgical prognoses. For these reasons, this expert consensus provides nine recommendations as a reference for standardizing and refining the diagnosis of pathological subtypes of iCCA, mainly based on the 5th edition of the World Health Organization Classification of Tumours of the Digestive System.

Liver cell therapies: cellular sources and grafting strategies

The liver has a complex cellular composition and a remarkable regenerative capacity. The primary cell types in the liver are two parenchymal cell populations, hepatocytes and cholangiocytes, that perform most of the functions of the liver and that are helped through interactions with non-parenchymal cell types comprising stellate cells, endothelia and various hemopoietic cell populations. The regulation of the cells in the liver is mediated by an insoluble complex of proteins and carbohydrates, the extracellular matrix, working synergistically with soluble paracrine and systemic signals. In recent years, with the rapid development of genetic sequencing technologies, research on the liver's cellular composition and its regulatory mechanisms during various conditions has been extensively explored. Meanwhile breakthroughs in strategies for cell transplantation are enabling a future in which there can be a rescue of patients with end-stage liver diseases, offering potential solutions to the chronic shortage of livers and alternatives to liver transplantation. This review will focus on the cellular mechanisms of liver homeostasis and how to select ideal sources of cells to be transplanted to achieve liver regeneration and repair. Recent advances are summarized for promoting the treatment of end-stage liver diseases by forms of cell transplantation that now include grafting strategies.

Locoregional Therapy for Intrahepatic Cholangiocarcinoma

Intrahepatic cholangiocarcinoma (ICC) has a poor prognosis, and surgical resection (SR) offers the only potential for cure. Unfortunately, only a small proportion of patients are eligible for resection due to locally advanced or metastatic disease. Locoregional therapies (LRT) are often used in unresectable liver-only or liver-dominant ICC. This review explores the role of these therapies in the treatment of ICC, including radiofrequency ablation (RFA), microwave ablation (MWA), transarterial chemoembolization (TACE), transarterial radioembolization (TARE), external beam radiotherapy (EBRT), stereotactic body radiotherapy (SBRT), hepatic arterial infusion (HAI) of chemotherapy, irreversible electroporation (IE), and brachytherapy. A search of the current literature was performed to examine types of LRT currently used in the treatment of ICC. We examined patient selection, technique, and outcomes of each type. Overall, LRTs are well-tolerated in the treatment of ICC and are effective in improving overall survival (OS) in this patient population. Further studies are needed to reduce bias from heterogenous patient populations and small sample sizes, as well as to determine whether certain LRTs are superior to others and to examine optimal treatment selection.

Heterogeneity of Cholangiocarcinoma Immune Biology

Cholangiocarcinomas (CCAs) are aggressive tumors arising along the biliary tract epithelium, whose incidence and mortality are increasing. CCAs are highly desmoplastic cancers characterized by a dense tumor microenvironment (TME), in which each single component plays a fundamental role in shaping CCA initiation, progression and resistance to therapies. The crosstalk between cancer cells and TME can affect the recruitment, infiltration and differentiation of immune cells. According to the stage of the disease and to intra- and inter-patient heterogeneity, TME may contribute to either protumoral or antitumoral activities. Therefore, a better understanding of the effect of each immune cell subtype may open the path to new personalized immune therapeutic strategies for the management of CCA. In this review, we describe the role of immune cells in CCA initiation and progression, and their crosstalk with both cancer-associated fibroblasts (CAFs) and the cancer-stem-cell-like (CSC) niche.

Surgical Strategies for Combined Hepatocellular-Cholangiocarcinoma (cHCC-CC)

Combined hepatocellular-cholangiocarcinoma (cHCC-CC) is a tumor entity presenting features of hepatocellular and cholangiocellular epithelial differentiation. Due to the likeness between cHCC-CC, HCC and CC, accurate pretherapeutical diagnosis is challenging and advanced stages are prevalent. Radical oncological surgery is the only curative therapeutical option in patients with cHCC-CC. To reach this goal a profound understanding of this rare liver tumor is crucial. Factors such as clinicopathological characteristics, growth patterns and biological behavior are of central importance. To explore onco-surgical strategies and aspects for complete resection of cHCC-CC and to answer important key questions, an extensive review of the literature was conducted to answer the following questions: What are the best surgical options? Is there a significance for nonanatomical resections? Is there a prognostic value of concomitant lymphadenectomy? What about multimodal concepts in local advanced cHCC-CC? The role of minimally invasive liver surgery (MILS) including the role of robotic liver surgery for cHCC-CC will be discussed. While liver transplantation (LT) is standard for patients with unresectable HCC, the role of LT in cHCC-CC patients is still controversial. How can patients with high risk for early tumor recurrence be identified to avoid aggressive surgical treatment without clinical benefit? The comprehensive understanding of this challenging liver tumor will help to improve future treatment options for these patients.

Implication of Ferroptosis in Cholangiocarcinoma: A Potential Future Target?

Cholangiocarcinoma (CCA), the second most common liver neoplasm, has a poor overall 5-year survival rate of less than 10%. A deeper understanding of the molecular pathogenesis contributing to CCA progression is essential for developing better therapeutic approaches to manage this disease. Ferroptosis, an oxidative iron-dependent form of regulated cell death, has been reported to be involved in tumorigenesis and progression. In particular, ferroptosis and inflammation, which are common issues in cholangiocarcinogenesis and CCA development, might be in concert with disease progression. Notably, the key feature of cancer cells is "iron addiction", which is crucial for the high metabolic demand in carcinogenesis and cancer progression. Additionally, iron metabolism is of great importance in ferroptosis. Moreover, that cancer cells are vulnerable to ferroptosis might be a possible mechanism of CCA development. Although the underlying mechanism of how ferroptosis is implicated in CCA development requires further investigation, developing a new strategy combined with a pro-ferroptotic treatment would be an exciting CCA treatment approach in the future.

Imaging Features of Premalignant Biliary Lesions and Predisposing Conditions with Pathologic Correlation

Biliary malignancies include those arising from the intrahepatic and extrahepatic bile ducts as well as the gallbladder and hepatopancreatic ampulla of Vater. The majority of intrahepatic and extrahepatic malignancies are cholangiocarcinomas (CCAs). They arise owing to a complex interplay between the patient-specific genetic background and multiple risk factors and may occur in the liver (intrahepatic CCA), hilum (perihilar CCA), or extrahepatic bile ducts (distal CCA). Biliary-type adenocarcinoma constitutes the most common histologic type of ampullary and gallbladder malignancies. Its prognosis is poor and surgical resection is considered curative, so early detection is key, with multimodality imaging playing a central role in making the diagnosis. There are several risk factors for biliary malignancy as well as predisposing conditions that increase the risk; this review highlights the pertinent imaging features of these entities with histopathologic correlation. The predisposing factors are broken down into three major categories: (a) congenital malformations such as choledochal cyst and pancreaticobiliary maljunction; (b) infectious or inflammatory conditions such as parasitic infections, hepatolithiasis, primary sclerosing cholangitis, and porcelain gallbladder; and (c) preinvasive epithelial neoplasms such as biliary intraepithelial neoplasm, intraductal papillary neoplasm of the bile duct, intra-ampullary papillary tubular neoplasm, and intracholecystic papillary neoplasm of the gallbladder. Recognizing the baseline features of these premalignant biliary entities and changes in their appearance over time that indicate the advent of malignancy in high-risk patients can lead to early diagnosis and potentially curative management. An invited commentary by Volpacchio is available online. Online supplemental material is available for this article. ^©RSNA, 2022.

Development and Characterization of Human Primary Cholangiocarcinoma Cell Lines

Cholangiocarcinoma (CCA) is the second most common primary liver tumor and is associated with late diagnosis, limited treatment options, and a 5-year survival rate of around 30%. CCA cell lines were first established in 1971, and since then, only 70 to 80 CCA cell lines have been established. These cell lines have been essential in basic and translational research to understand and identify novel mechanistic pathways, biomarkers, and disease-specific genes. Each CCA cell line has unique characteristics, reflecting a specific genotype, sex-related properties, and patient-related signatures, making them scientifically and commercially valuable. CCA cell lines are crucial in the use of novel technologies, such as three-dimensional organoid models, which help to model the tumor microenvironment and cell-to-cell crosstalk between tumor-neighboring cells. This review highlights crucial information on CCA cell lines, including: i) type of CCA (eg, intra- or extrahepatic), ii) isolation source (eg, primary tumor or xenograft), iii) chemical digestion method (eg, trypsin or collagenase), iv) cell-sorting method (colony isolation or removal of fibroblasts), v) maintenance-medium choice (eg, RPMI or Dulbecco's modified Eagle's medium), vi) cell morphology (eg, spindle or polygonal shape), and vii) doubling time of cells.

Future challenges in gastroenterology and hepatology, between innovations and unmet needs: A SIGE Young Editorial Board's perspective

Gastroenterology, Digestive Endoscopy and Hepatology have faced significant improvements in terms of diagnosis and therapy in the last decades. However, many fields still remain poorly explored, and many questions unanswered. Moreover, basic-science, as well as translational and clinical discoveries, together with technology advancement will determine further steps toward a better, refined care for many gastroenterological disorders in the future. Therefore, the Young Investigators of the Italian Society of Gastroenterology (SIGE) joined together, offering a perspective on major future innovations in some hot clinical topics in Gastroenterology, Endoscopy, and Hepatology, as well as the current pitfalls and the grey zones.

Comparison of growth features and cancer stem cell prevalence in intrahepatic and extrahepatic cholangiocarcinoma cell lines

Aim of the study

Intra- and extrahepatic cholangiocarcinoma (I-CCA and E-CCA respectively) exhibit different growth features that contribute to different clinical outcomes. Cancer stem cells (CSCs) influence tumor growth and thereby may be responsible for these differences. The aim of this study was to document and compare the growth features of human I-CCA and E-CCA cell lines and determine whether any differences observed could be explained by differences in the prevalence and/or stem cell surface marker (SCSM) expression profiles of CSCs within the tumor cell lines.

Material and methods

Six CCA cells lines, three I-CCA and three E-CCA, were studied. Tumor cell growth features including cell proliferation, colony/spheroid formation, migration and invasion were documented. CSC prevalence and SCSM expression profiles were examined by flow cytometry.

Results

I-CCA cells had significantly increased proliferative activity, shorter doubling times and were more invasive than E-CCA cells, while colony/spheroid formation and migration were similar in the two cell populations. There were no significant differences in CSC prevalence rates or SCSM expression profiles.

Conclusions

These findings suggest that I-CCA cells proliferate at a more rapid rate and are more invasive than E-CCA cells but the differences cannot be explained by differences in the prevalence or SCSM expression profiles of CSCs within the tumor cell population.

Imaging Spectrum of Intrahepatic Mass-Forming Cholangiocarcinoma and Its Mimickers: How to Differentiate Them Using MRI

Intrahepatic cholangiocarcinoma (ICC) is the second most common primary hepatic malignancy, with mass-forming growth pattern being the most common. The typical imaging appearance of mass-forming ICC (mICC) consists of irregular ring enhancement in the arterial phase followed by the progressive central enhancement on portal venous and delayed phases. However, atypical imaging presentation in the form of hypervascular mICC might also be seen, which can be attributed to distinct pathological characteristics. Ancillary imaging features such as lobular shape, capsular retraction, segmental biliary dilatation, and vascular encasement favor the diagnosis of mICC. Nevertheless, these radiological findings may also be present in certain benign conditions such as focal confluent fibrosis, sclerosing hemangioma, organizing hepatic abscess, or the pseudosolid form of hydatid disease. In addition, a few malignant lesions including primary liver lymphoma, hemangioendothelioma, solitary hypovascular liver metastases, and atypical forms of hepatocellular carcinoma (HCC), such as scirrhous HCC, infiltrative HCC, and poorly differentiated HCC, may also pose a diagnostic dilemma by simulating mICC in imaging studies. Diffusion-weighted imaging and the use of hepatobiliary contrast agents might be helpful for differential diagnosis in certain cases. The aim of this manuscript is to provide a comprehensive overview of mICC imaging features and to describe useful tips for differential diagnosis with its potential mimickers.

Circulating Cell-Free DNA-Based Comprehensive Molecular Analysis of Biliary Tract Cancers Using Next-Generation Sequencing

Biliary tract cancer (BTC) is a rare malignancy with a long disease course and an overall poor prognosis. Despite multiple chemotherapy agents, there is no defined second-line treatment opportunity for advanced BTCs. In the era of precision oncology, NGS plays an important role in identifying mutations that may predict the molecular pathomechanism and manage the BTC therapy. The peripheral blood liquid biopsy (LB) of cancer patients represents variable amounts of cell-free DNA (cfDNA) released from tumor foci of any anatomical location. Our study aimed to identify somatic mutations and tumor variant burden (TVB) in cell-free and matched tumor DNA. We found a positive correlation between the estimated tumor volume and cfDNA yield (r = 0.9326, p < 0.0001). Comparing tissue and LB results, similar TVB was observed. SNVs were proven in 84% of the cases, while in two cases, only the LB sample was informative for molecular analysis. The most important aberrations in BTCs, such as FGFR2, IDH1, IDH2, KRAS, and TP53, could be detected in matched LB samples. Our prospective study demonstrates a minimally invasive testing approach to identify molecular genetic alterations in cholangiocarcinoma and gallbladder cancers. Clinical applications of cfDNA reflect by capturing the outstanding spatial tumor heterogeneity and guarantee novel aspects for the precision oncology treatment.

The Role of the Hedgehog Pathway in Cholangiocarcinoma

Simple Summary

Cholangiocarcinoma (CCA) is one of the most refractory malignancies with a high mortality rate. Among all the pathways involved in CCA development, emerging evidence highlights Hedgehog (HH) signaling as a substantial player in CCA-genesis and development. The pro-tumoral function of HH provides potential therapeutic implications, and recently the use of HH inhibitors has paved the way for clinical application in various solid tumors. Targeting HH members, namely Hedgehog ligands, SMO transmembrane protein and GLI transcription factors may thus confer therapeutic options for the improvement of CCA treatment outcome.

Abstract

Cholangiocarcinoma (CCA) is a poorly treatable type of cancer and, along with hepatocellular carcinoma (HCC), is the predominant type of primitive liver cancer in adults. The lack of understanding of CCA biology has slowed down the identification of novel targets and the development of effective treatments. While tumors share some general characteristics, detailed knowledge of specific features is essential for the development of effectively tailored therapeutic approaches. The Hedgehog (HH) signaling cascade regulates stemness biology, embryonal development, tissue homeostasis, and cell proliferation and differentiation. Its aberrant activation has been associated with a variety of solid and hematological human malignancies. Several HH-inhibiting compounds have been indeed developed as potential anticancer agents in different types of tumors, with Smoothened and GLI inhibitors showing the most promising results. Beside its well-established function in other tumors, findings regarding the HH signaling in CCA are still controversial. Here we will give an overview of the most important clinical and molecular features of cholangiocarcinoma, and we will discuss the available evidence of the crosstalk between the HH signaling pathway and the cholangiocarcinoma cell biology.

Imaging of Intrahepatic Cholangiocarcinoma

Cholangiocarcinoma is the second most common primary hepatic malignancy and is a heterogeneous tumor of biliary epithelium. We discuss the risk factors, anatomic classification of cholangiocarcinoma (CC) as well as the different morphologic subtypes of CC. Imaging findings of CC on different modalities are described, focusing on intrahepatic CC. Recently recognized imaging features that carry prognostic significance, such as a worse prognosis in tumors that have more desmoplastic stroma, are detailed. Other benign and malignant entities that should be considered in the differential diagnosis of CC will also be discussed.

Molecular Landscape and Therapeutic Strategies in Cholangiocarcinoma: An Integrated Translational Approach towards Precision Medicine

Cholangiocarcinomas (CCAs) are heterogeneous biliary tract malignancies with dismal prognosis, mainly due to tumor aggressiveness, late diagnosis, and poor response to current therapeutic options. High-throughput technologies have been used as a fundamental tool in unveiling CCA molecular landscape, and several molecular classifications have been proposed, leading to various targeted therapy trials. In this review, we aim to analyze the critical issues concerning the status of precision medicine in CCA, discussing molecular signatures and clusters, related to both anatomical classification and different etiopathogenesis, and the latest therapeutic strategies. Furthermore, we propose an integrated approach comprising the CCA molecular mechanism, pathobiology, clinical and histological findings, and treatment perspectives for the ultimate purpose of improving the methods of patient allocations in clinical trials and the response to personalized therapies.

Tumor-associated macrophages in cholangiocarcinoma: complex interplay and potential therapeutic target

Cholangiocarcinoma (CCA) is an aggressive and multifactorial malignancy of the biliary tract. The carcinogenesis of CCA is associated with genomic and epigenetic abnormalities, as well as environmental effects. However, early clinical diagnosis and reliable treatment strategies of CCA remain unsatisfactory. Multiple compartments of the tumor microenvironment significantly affect the progression of CCA. Tumor-associated macrophages (TAMs) are a type of plastic immune cells that are recruited and activated in the CCA microenvironment, especially at the tumor invasive front and perivascular sites. TAMs create a favorable environment that benefits CCA growth by closely interacting with CCA cells and other stromal cells via releasing multiple protumor factors. In addition, TAMs exert immunosuppressive and antichemotherapeutic effects, thus intensifying the malignancy. Targeting TAMs may provide an improved understanding of, and novel therapeutic approaches for, CCA. This review focuses on revealing the interplay between TAMs and CCA.

Current challenges to underpinning the genetic basis for cholangiocarcinoma

AREAS COVERED

This review provides an overview regarding the current scenario and knowledge of the CCA genomic landscape and the potentially actionable molecular aberrations in each CCA subtype.

EXPERT OPINION

The establishment and advances of high-throughput methodologies applied to genetic and epigenetic profiling are changing many cancer types' therapeutic landscape , including CCA.The large body of data generated must be interpreted appropriately and eventually implemented in clinical practice. The following advancements toward precision medicine in CCA management will require designing better clinical trials with improved methods to stratify biliary tumor patients.

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.

A New Option for the Treatment of Intrahepatic Cholangiocarcinoma: Percutaneous Hepatic Perfusion with CHEMOSAT Delivery System

Liver metastases are a major management problem; since they occur in tumors of different origin, they are often multiple, difficult to visualize and can lie dormant for many years. Patients with liver metastases usually die of their disease, mostly due to liver failure, since systemic treatments are unable to eradicate micro-metastasis, and interventional loco-regional procedures cannot treat all existing ones. Cholangiocarcinoma (CCA) is the second most common primary liver tumor, showing a poor overall prognosis. When resection is not possible, treatment options include tumor-focused or local ablative therapy, organ-focused or regional therapy and systemic therapy. We reviewed available loco-regional therapeutic options, with particular focus on the CHEMOSAT® Melphalan/Hepatic Delivery System (CS-HDS), which is uniquely positioned to perform a percutaneous hepatic perfusion (PHP), in order to treat the entire liver as a standalone or as complementary therapy. This system isolates the liver circulation, delivers a high concentration of chemotherapy (melphalan), filters most chemotherapy out of the blood and is a repeatable procedure. Most CS-HDS benefits are demonstrated in liver-predominant diseases, like liver metastasis from uveal melanoma (UM), hepatocarcinoma (HCC) and CCA. More than 650 procedures have been performed in Europe to date, mostly to treat liver metastases from UM. In CCA, experience is still limited, but retrospective analyses have been reported, while phase II and III studies are closed, waiting for results or ongoing.

Intrahepatic cholangiocarcinoma: Morpho-molecular pathology, tumor reactive microenvironment, and malignant progression

Intrahepatic cholangiocarcinoma (iCCA) is a relatively rare, but highly lethal and biologically complex primary biliary epithelial cancer arising within liver. After hepatocellular carcinoma, iCCA is the second most common primary liver cancer, accounting for approximately 10-20% of all primary hepatic malignancies. Over the last 10-20 years, iCCA has become the focus of increasing concern largely due to its rising incidence and high mortality rates in various parts of the world, including the United States. The challenges posed by iCCA are daunting and despite recent progress in the standard of care and management options for iCCA, the prognosis for this cancer continues to be dismal. In an effort to provide a framework for advancing our understanding of iCCA malignant aggressiveness and therapy resistance, this review will highlight key etiological, biological, molecular, and microenvironmental factors hindering more effective management of this hepatobiliary cancer. Particular focus will be on critically reviewing the cell origins and morpho-molecular heterogeneity of iCCAs, providing mechanistic insights into high risk fibroinflammatory cholangiopathies associated with iCCA development, and notably discussing the deleterious role played by the tumor reactive desmoplastic stroma in regulating iCCA malignant progression, lymphangiogenesis, and tumor immunobiology.

Pathogenesis of Cholangiocarcinoma

Cholangiocarcinoma (CCA) encompasses a group of malignancies that can arise at any point in the biliary tree. Although considered a rare cancer, the incidence of CCA is increasing globally. The silent and asymptomatic nature of these tumors, particularly in their early stages, in combination with their high aggressiveness, intra- and intertumor heterogeneity, and chemoresistance, significantly compromises the efficacy of current therapeutic options, contributing to a dismal prognosis. During the last few years, increasing efforts have been made to unveil the etiologies and pathogenesis of these tumors and to develop more effective therapies. In this review, we summarize current findings in the field of CCA, mainly focusing on the mechanisms of pathogenesis, cells of origin, genomic and epigenetic abnormalities, molecular alterations, chemoresistance, and therapies.

Peritumoral ductular reaction can be a prognostic factor for intrahepatic cholangiocarcinoma

Background

Peritumoral ductular reaction (DR) was reported to be related to the prognosis of combined hepatocellular-cholangiocarcinoma and hepatocellular carcinoma. Non-mucin-producing intrahepatic cholangiocarcinoma (ICC) which may be derived from small bile duct cells or liver progenitor cells (LPCs) was known to us. However, whether peritumoral DR is also related to non-mucin-producing ICCs remains to be investigated.

Methods

Forty-seven patients with non-mucin-producing ICC were eventually included in the study and clinicopathological variables were collected. Immunohistochemical analysis and immunofluorescence staining for cytokeratin 19, proliferating cell nuclear antigen, and α-smooth muscle actin were performed in tumor and peritumor liver tissues.

Results

A significant correlation existed between peritumoral DR and local inflammation and fibrosis. (r = 0.357, 95% CI, 0.037–0.557; P = 0.008 and r = 0.742, 95% CI, 0.580–0.849; P < 0.001, respectively). Patients with obvious peritumoral DR had high recurrence rate (81.8% vs 56.0%, P = 0.058) and poor overall and disease-free survival time (P = 0.01 and P = 0.03, respectively) comparing with mild peritumoral DR. Compared with the mild peritumoral DR group, the proliferation activity of LPCs/ cholangiocytes was higher in obvious peritumoral DR, which, however, was not statistically significant. (0.43 ± 0.29 vs 0.28 ± 0.31, P = 0.172). Furthermore, the correlation analysis showed that the DR grade was positively related to the portal/septalα-SMA level (r = 0.359, P = 0.001).

Conclusions

Peritumoral DR was associated with local inflammation and fibrosis. Patients with non-mucin-producing ICC having obvious peritumoral DR had a poor prognosis. Peritumoral DR could be a prognostic factor for ICC. However, the mechanism should be further investigated.

Intrahepatic cholangiocarcinomas with IDH1/2 mutation-associated hypermethylation at selective genes and their clinicopathological features

Intrahepatic cholangiocarcinoma (ICC) is a rare but fatal tumor. The isocitrate dehydrogenase 1 and 2 (IDH1/2) genes are known to be mutated in ICC. IDH1/2 mutations tend to be accompanied by enhanced hypermethylation at a subset of genomic loci. We sought to clarify the clinicopathological features, including prognostic value, of ICCs with IDH1/2 mutation-associated hypermethylation at a subset of genes. The mutation status of IDH1/2 and methylation status of 30 gene CpG island loci were analyzed in 172 cases of ICC using pyrosequencing and the MethyLight assay, respectively. The mutation status of IDH1/2 was correlated with clinicopathological features and the DNA methylation status at 30 gene loci. Then, the clinicopathological characteristics were analyzed regarding three-tiered methylation statuses in genes showing IDH1/2 mutation-associated methylation. IDH1/2 mutations were found in 9.3% of ICCs, and IDH1/2-mutated tumors were associated with the histological subtype, including the bile ductular type and small duct type, and poor differentiation. Eight DNA methylation markers showed associations with IDH1/2 mutations, and ICCs with > 5/8 methylated markers were associated with the bile ductular type or small duct type, absence of mucin production, absence of biliary intraepithelial neoplasia, and presence of chronic liver disease. > 5/8 methylated markers were an independent prognostic marker associated with better survival in both cancer-specific survival and recurrence-free survival. In summary, by analyzing the association between IDH1/2 mutations and DNA methylation in individual genes, we developed a panel of DNA methylation markers that were significantly associated with IDH1/2 mutations and were able to identify a subset of ICC with better clinical outcomes.

Cholangiocarcinoma 2020: the next horizon in mechanisms and management

Cholangiocarcinoma (CCA) includes a cluster of highly heterogeneous biliary malignant tumours that can arise at any point of the biliary tree. Their incidence is increasing globally, currently accounting for ~15% of all primary liver cancers and ~3% of gastrointestinal malignancies. The silent presentation of these tumours combined with their highly aggressive nature and refractoriness to chemotherapy contribute to their alarming mortality, representing ~2% of all cancer-related deaths worldwide yearly. The current diagnosis of CCA by non-invasive approaches is not accurate enough, and histological confirmation is necessary. Furthermore, the high heterogeneity of CCAs at the genomic, epigenetic and molecular levels severely compromises the efficacy of the available therapies. In the past decade, increasing efforts have been made to understand the complexity of these tumours and to develop new diagnostic tools and therapies that might help to improve patient outcomes. In this expert Consensus Statement, which is endorsed by the European Network for the Study of Cholangiocarcinoma, we aim to summarize and critically discuss the latest advances in CCA, mostly focusing on classification, cells of origin, genetic and epigenetic abnormalities, molecular alterations, biomarker discovery and treatments. Furthermore, the horizon of CCA for the next decade from 2020 onwards is highlighted.