Cytokeratin profile relates to histological subtypes and intrahepatic location of intrahepatic cholangiocarcinoma and primary sites of metastatic adenocarcinoma of liver

Identification of prognostic biomarkers for cholangiocarcinoma by combined analysis of molecular characteristics of clinical MVI subtypes and molecular subtypes

Cholangiocarcinoma (CCA) is widely noted for its high degree of malignancy, rapid progression, and limited therapeutic options. This study was carried out on transcriptome data of 417 CCA samples from different anatomical locations. The effects of lipid metabolism related genes and immune related genes as CCA classifiers were compared. Key genes were derived from MVI subtypes and better molecular subtypes. Pathways such as epithelial mesenchymal transition (EMT) and cell cycle were significantly activated in MVI-positive group. CCA patients were classified into three (four) subtypes based on lipid metabolism (immune) related genes, with better prognosis observed in lipid metabolism-C1, immune-C2, and immune-C4. IPTW analysis found that the prognosis of lipid metabolism-C1 was significantly better than that of lipid metabolism-C2 + C3 before and after correction. KRT16 was finally selected as the key gene. And knockdown of KRT16 inhibited proliferation, migration and invasion of CCA cells.

Recommendations on maximising the clinical value of tissue in the management of patients with intrahepatic cholangiocarcinoma

Background & Aims

Patients with intrahepatic cholangiocarcinoma can now be managed with targeted therapies directed against specific molecular alterations. Consequently, tissue samples submitted to the pathology department must produce molecular information in addition to a diagnosis or, for resection specimens, staging information. The pathologist's role when evaluating these specimens has therefore changed to accommodate such personalised approaches.

Methods

We developed recommendations and guidance for pathologists by conducting a systematic review of existing guidance to generate candidate statements followed by an international Delphi process. Fifty-nine pathologists from 28 countries in six continents rated statements mapped to all elements of the specimen pathway from receipt in the pathology department to authorisation of the final written report. A separate survey of 'end-users' of the report including surgeons, oncologists, and gastroenterologists was undertaken to evaluate what information should be included in the written report to enable appropriate patient management.

Results

Forty-eight statements reached consensus for inclusion in the guidance including 10 statements about the content of the written report that also reached consensus by end-user participants. A reporting proforma to allow easy inclusion of the recommended data points was developed.

Conclusions

These guiding principles and recommendations provide a framework to allow pathologists reporting on patients with intrahepatic cholangiocarcinoma to maximise the informational yield of specimens required for personalised patient management.

Impact and Implications

Biopsy or resection lesional tissue from intrahepatic cholangiocarcinoma must yield information about the molecular abnormalities within the tumour that define suitability for personalised therapies in addition to a diagnosis and staging information. Here, we have developed international consensus guidance for pathologists that report such cases using a Delphi process that sought the views of both pathologists and 'end-users of pathology reports. The guide highlights the need to report cases in a way that preserves tissue for molecular testing and emphasises that reporting requires interpretation of histological characteristics within the broader clinical and radiological context. The guide will allow pathologists to report cases of intrahepatic cholangiocarcinoma in a uniform manner that maximises the value of the tissue received to facilitate optimal multidisciplinary patient management.

A pancreatic adenocarcinoma mimicking hepatoid carcinoma of uncertain histogenesis: A case report and literature review

In rare cases, metastatic adenocarcinomas of different origin may exhibit the features of hepatoid carcinoma (HC), a rare malignant epithelial tumor, most commonly occurring in the ovaries and stomach, as well as in the pancreas and biliary ducts. A case of a 72-year-old female patient who developed a highly aggressive, poorly differentiated pancreatic ductal adenocarcinoma with peritoneal carcinomatosis, demonstrating hepatoid differentiation upon conventional hematoxylin and eosin staining is reported in the present study. The patient presented with severe abdominal pain, and the radiological investigations performed revealed ovarian and hepatic tumor masses and peritoneal lesions, which were surgically removed. The gross examination of the peritoneum and omentum revealed multiple solid, firm, grey-white nodules, diffusely infiltrating the adipose tissue. The microscopic examination revealed a malignant epithelial proliferation, composed of polygonal cells with abundant eosinophilic cytoplasm and irregular, pleomorphic nuclei. Certain cells presented with intracytoplasmic mucus inclusions, raising suspicion of a HC with an uncertain histogenesis. Immunohistochemical staining was performed, and the tumor cells were found to be positive for cytokeratin (CK)7, CK18 and mucin 5AC, whereas negative staining for CK20, caudal-type homeobox transcription factor 2, α-fetoprotein, paired box gene 8, GATA-binding protein 3 and Wilms tumor 1 were documented. Thus, the diagnosis of metastatic pancreatic adenocarcinoma was established. The main aim of the present study was to provide further knowledge concerning poorly differentiated metastatic adenocarcinoma resembling HC, emphasizing the histopathological and immunohistochemical features of these malignant lesions and raising awareness of the diagnostic difficulties that may arise, as well as the importance of the use immunohistochemistry in differentiating carcinomas of uncertain histogenesis.

EASL-ILCA Clinical Practice Guidelines on the management of intrahepatic cholangiocarcinoma

Intrahepatic cholangiocarcinoma (iCCA) develops inside the liver, between bile ductules and the second-order bile ducts. It is the second most frequent primary liver cancer after hepatocellular carcinoma, and its global incidence is increasing. It is associated with an alarming mortality rate owing to its silent presentation (often leading to late diagnosis), highly aggressive nature and resistance to treatment. Early diagnosis, molecular characterisation, accurate staging and personalised multidisciplinary treatments represent current challenges for researchers and physicians. Unfortunately, these challenges are beset by the high heterogeneity of iCCA at the clinical, genomic, epigenetic and molecular levels, very often precluding successful management. Nonetheless, in the last few years, progress has been made in molecular characterisation, surgical management, and targeted therapy. Recent advances together with the awareness that iCCA represents a distinct entity amongst the CCA family, led the ILCA and EASL governing boards to commission international experts to draft dedicated evidence-based guidelines for physicians involved in the diagnostic, prognostic, and therapeutic management of iCCA.

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.

Diagnostic and prognostic impact of cytokeratin 19 expression analysis in human tumors: a tissue microarray study of 13,172 tumors

To evaluate cytokeratin 19 (CK19) expression in normal and cancerous tissues, 15,977 samples from 122 tumor types and 608 samples of 76 normal tissue types were analyzed by immunohistochemistry (IHC). In normal tissues, CK19 expression occurred in epithelial cells of most glandular organs but was strictly limited to the basal cell layer of nonkeratinizing squamous epithelium and absent in the skin. CK19 expression in ≥90% of cases was seen in 34% of the tumor entities including the adenocarcinomas of the pancreas (99.4%), colorectum (99.8%), esophagus (98.7%), and stomach (97.7%), as well as breast cancer (90.0%-100%), high-grade serous (99.1%) or endometrioid (97.8%) ovarian cancer, and urothelial carcinoma (92.6%-100%). A low CK19 positivity rate (0.1-10%) was seen in 5 of 122 tumor entities including hepatocellular carcinoma and seminoma. A comparison of tumor versus normal tissue findings demonstrated that upregulation and downregulation of CK19 can occur in cancer and that both alterations can be linked to unfavorable phenotypes. CK19 downregulation was linked to high grade (p = 0.0017) and loss of estrogen receptor- and progesterone receptor-expression (p < 0.0001 each) in invasive breast carcinoma of no special type. CK19 upregulation was linked to nodal metastases in neuroendocrine tumors and papillary thyroid carcinomas (p < 0.05 each) and to poor grade in clear cell renal cell carcinoma (p < 0.05). CK19 upregulation was particularly common in squamous cell carcinomas. We concluded that CK19 IHC might separate primary liver cell carcinoma from liver metastases, seminoma from other testicular tumors, and helps in the detection of early neoplastic transformation in squamous epithelium.

Liver metastases

Liver metastases are commonly detected in a range of malignancies including colorectal cancer (CRC), pancreatic cancer, melanoma, lung cancer and breast cancer, although CRC is the most common primary cancer that metastasizes to the liver. Interactions between tumour cells and the tumour microenvironment play an important part in the engraftment, survival and progression of the metastases. Various cells including liver sinusoidal endothelial cells, Kupffer cells, hepatic stellate cells, parenchymal hepatocytes, dendritic cells, resident natural killer cells as well as other immune cells such as monocytes, macrophages and neutrophils are implicated in promoting and sustaining metastases in the liver. Four key phases (microvascular, pre-angiogenic, angiogenic and growth phases) have been identified in the process of liver metastasis. Imaging modalities such as ultrasonography, CT, MRI and PET scans are typically used for the diagnosis of liver metastases. Surgical resection remains the main potentially curative treatment among patients with resectable liver metastases. The role of liver transplantation in the management of liver metastasis remains controversial. Systemic therapies, newer biologic agents (for example, bevacizumab and cetuximab) and immunotherapeutic agents have revolutionized the treatment options for liver metastases. Moving forward, incorporation of genetic tests can provide more accurate information to guide clinical decision-making and predict prognosis among patients with liver metastases.

Diagnostic and prognostic impact of cytokeratin 18 expression in human tumors: a tissue microarray study on 11,952 tumors

BACKGROUND

Cytokeratin 18 (CK18) is an intermediate filament protein of the cytokeratin acidic type I group and is primarily expressed in single-layered or "simple" epithelial tissues and carcinomas of different origin.

METHODS

To systematically determine CK18 expression in normal and cancerous tissues, 11,952 tumor samples from 115 different tumor types and subtypes (including carcinomas, mesenchymal and biphasic tumors) as well as 608 samples of 76 different normal tissue types were analyzed by immunohistochemistry in a tissue microarray format.

RESULTS

CK18 was expressed in normal epithelial cells of most organs but absent in normal squamous epithelium. At least an occasional weak CK18 positivity was seen in 90 of 115 (78.3%) tumor types. Wide-spread CK18 positivity was seen in 37 (31.9%) of tumor entities, including adenocarcinomas of the lung, prostate, colon and pancreas as well as ovarian cancer. Tumor categories with variable CK18 immunostaining included cancer types arising from CK18 positive precursor cells but show CK18 downregulation in a fraction of cases, tumor types arising from CK18 negative precursor cells occasionally exhibiting CK18 neo-expression, tumors derived from normal tissues with variable CK18 expression, and tumors with a mixed differentiation. CK18 downregulation was for example seen in renal cell cancers and breast cancers, whereas CK18 neo-expression was found in squamous cell carcinomas of various origins. Down-regulation of CK18 in invasive breast carcinomas of no special type and clear cell renal cell carcinomas (ccRCC) was related to adverse tumor features in both tumors (p ≤ 0.0001) and poor patient prognosis in ccRCC (p = 0.0088). Up-regulation of CK18 in squamous cell carcinomas was linked to high grade and lymph node metastasis (p < 0.05). In summary, CK18 is consistently expressed in various epithelial cancers, especially adenocarcinomas.

CONCLUSIONS

Down-regulation or loss of CK18 expression in cancers arising from CK18 positive tissues as well as CK18 neo-expression in cancers originating from CK18 negative tissues is linked to cancer progression and may reflect tumor dedifferentiation.

Cancer of Unknown Primary: Challenges and Progress in Clinical Management

Simple Summary

Patients with cancer of unknown primary site suffer the burden of an uncertain disease, which is characterized by the impossibility to identify the tissue where the tumor has originated. The identification of the primary site of a tumor is of great importance for the patient to have access to site-specific treatments and be enrolled in clinical trials. Therefore, patients with cancer of unknown primary have reduced therapeutic opportunities and poor prognosis. Advancements have been made in the molecular characterization of this tumor, which could be used to infer the tumor site-of-origin and thus broaden the diagnostic outcome. Moreover, we describe here the novel therapeutic opportunities that are based on the genetic and immunophenotypic characterization of the tumor, and thus independent from the tumor type, which could provide most benefit to patients with cancer of unknown primary.

Abstract

Distant metastases are the main cause of cancer-related deaths in patients with advanced tumors. A standard diagnostic workup usually contains the identification of the tissue-of-origin of metastatic tumors, although under certain circumstances, it remains elusive. This disease setting is defined as cancer of unknown primary (CUP). Accounting for approximately 3–5% of all cancer diagnoses, CUPs are characterized by an aggressive clinical behavior and represent a real therapeutic challenge. The lack of determination of a tissue of origin precludes CUP patients from specific evidence-based therapeutic options or access to clinical trial, which significantly impacts their life expectancy. In the era of precision medicine, it is essential to characterize CUP molecular features, including the expression profile of non-coding RNAs, to improve our understanding of CUP biology and identify novel therapeutic strategies. This review article sheds light on this enigmatic disease by summarizing the current knowledge on CUPs focusing on recent discoveries and emerging diagnostic strategies.

CK20 and lymph node involvement predict adverse outcome of malignant intraductal papillary neoplasm of the bile duct

OBJECTIVES

To identify prognostic factors of malignant intraductal papillary neoplasm of the bile duct (m-IPNB).

MATERIALS AND METHODS

We included 38 consecutive cases which underwent surgical resection and diagnosed as IPNB with malignant component from January 2003 to January 2017. Clinicopathological variables were collected to conduct survival analysis and identify prognostic factors.

RESULTS

The median overall survival (OS) of m-IPNB was 76.0 months, with 1-, 3-, and 5-year survival rates of 97.2%, 73.5%, and 59.8%, respectively. The median RFS was 48.0 months with 1-, 3-, and 5-year recurrence-free survival (RFS) rate was 83.2%, 59.8%, and 44.6%, respectively. Univariate analysis showed that elevation of carcinoembryonic antigen CEA, lymph node involvement, resection margin status, degree of periductal invasion, and positive expression of CK20 were associated with both OS and RFS of m-IPNB. After multivariate Cox models analysis, lymph node involvement and positive expression of CK20 were identified as independent prognostic factors for OS, while lymph node involvement and resection margin status were independent prognostic factors for RFS. The median OS of patients with m-IPNB involving lymphatic metastases and positive expression of CK20 was 27.0±8.8 months and 51.0±12.4 months, respectively. The median RFS of cases with lymph node involvement and R1 resection was 10.0±3.3 months and 25.0±6.9 months, respectively. However, there was no significant difference in OS or RFS between cases of pancreaticobiliary and intestinal subtype.

CONCLUSIONS

Lymph node involvement and positive expression of CK20 are independent prognostic factors for shorter OS of m-IPNB, while patients with lymph node involvement and positive resection margin are at higher risk of tumor recurrence.

Gallbladder cancer harboring ERBB2 mutation on the primary and metastatic site: A case report

BACKGROUND

Bile duct cancer constitutes gallbladder cancer (GBC), intrahepatic cholangiocarcinoma (ICA), and extrahepatic cholangiocarcinoma (ECA). These three entities show morphological and immunohistochemical resemblance so that it is difficult to differentiate between primary ICA and liver metastasis of GBC, which sometimes becomes a point of discussion in clinical practice. Although these cancers demonstrate significant differences in their mutational landscape, several reports demonstrated shared genomic alteration in paired primary and metastatic site aids in distinguishing metastatic recurrence from second primary cancers.

CASE SUMMARY

We present a 73-year-old female patient who underwent curative resection for GBC harboring epidermal growth factor receptor 2 (ERBB2) activating mutation on next-generation sequencing (NGS)-based genomic testing. One year later, a hepatic lesion was observed on follow-up imaging and she underwent surgical resection for a pathological diagnosis. The histological findings of the hepatic lesion were similar to those of the primary lesion. Additionally, using NGS panel testing, the hepatic lesion was found to have ERBB2 activating mutation, which is the identical mutation detected in the sequencing result of the primary site. ERBB2 activating mutation occurs more frequently in GBC than ICA and ECA. Therefore, in the present case, we think this molecular finding potentiated the diagnosis of the liver mass toward a metastatic recurrence. Additionally, this patient underwent HER2-targeted treatment with lapatinib in combination with capecitabin and obtained clinical benefit.

CONCLUSION

This case illustrated NGS panel usefulness in distinguishing GBC recurrence from second primary cancer and HER2-targeted agent efficacy on ERBB2 mutated GBC.

SOX9 expression decreases survival of patients with intrahepatic cholangiocarcinoma by conferring chemoresistance

BACKGROUND

Sex-determining region Y-box (SRY-box) containing gene 9 (SOX9) expression confers cancer stem cell features. However, SOX9 function in intrahepatic cholangiocarcinoma (iCCA) is unknown. This study investigated the effects and underlying mechanisms of SOX9 in iCCA.

METHODS

SOX9 expression in 59 iCCA patients was examined by immunohistochemistry. The association between SOX9 expression and clinical outcome was evaluated. Gene signature and biological functions of SOX9 in iCCA were examined in vitro.

RESULTS

iCCA patients with high SOX9 expression had shorter survival time than those with low SOX9. In patients receiving chemotherapy, median survival time in patients with low and high levels of SOX9 were 62 and 22 months, respectively. In vitro, gemcitabine increased SOX9 expression in iCCA cells. When SOX9 was knocked down, gemcitabine-induced apoptosis was markedly increased. Silencing SOX9 significantly inhibited gemcitabine-induced phosphorylation of checkpoint kinase 1, a key cell cycle checkpoint protein that coordinates the DNA damage response and inhibited the expression of multidrug resistance genes. Microarray analyses showed that SOX9 knockdown in CCA cells altered gene signatures associated with multidrug resistance and p53 signalling.

CONCLUSIONS

SOX9 governs the response of CCA cells to chemotherapy. SOX9 is a biomarker to select iCCA patients eligible for efficient chemotherapy.

Budd-Chiari Syndrome and Esophageal Achalasia: Unrecognized Intrahepatic Cholangiocarcinoma Invading Multiple Organs

Intrahepatic cholangiocarcinoma (ICC) is the second-most common primary liver cancer, although its occurrence is relatively rare. Budd-Chiari syndrome (BCS) is characterized by outflow obstruction from the liver, with hepatocellular carcinoma being the most common cause of malignant BCS. In this case report, we describe the occurrence of an unrecognized ICC that induced BCS and esophageal achalasia.

Gallbladder papillary neoplasms share pathological features with intraductal papillary neoplasm of the bile duct

Intraductal papillary neoplasm of the bile duct (IPNB) has been widely recognized. However, the knowledge of intracystic papillary neoplasm of the gallbladder (IPNG) including papillary adenoma and adenocarcinoma is not well defined. In this study, we compared the clinicopathological and immunohistochemical features between 32 IPNG cases and 32 IPNB cases. IPNG-1 (low-high grade dysplasia) exhibited an earlier onset age, smaller tumor size and lower level of CK20 expression compared to IPNG-2 (invasive carcinoma). Histologically, pancreaticobiliary and intestinal subtype accounted for nearly half of IPNG or IPNB (44.4% and 48.1% vs. 44.0% and 44.0%), respectively. Immunohistochemically, 88.9% of IPNG and 92.0% of IPNB cases were positive for MUC1, and 96.3% and 92.0% for CK7, respectively. CDX2 and MUC2 were more highly expressed in the intestinal subtype than in other subtypes. CK20 expression increased in parallel with tumor progression. In addition, 53.1% of IPNG cases and 68.6% of IPNB cases exhibited invasive carcinoma, and showed significant survival advantages to conventional gallbladder adenocarcinoma and cholangiocarcinoma, respectively. In conclusion, papillary adenoma and adenocarcinoma of the gallbladder can be recognized as different pathological stages of IPNG, and they share pathological features with IPNB.

Comparative Analysis of Immunohistochemical Markers for Differential Diagnosis of Hepatocelluar Carcinoma and Cholangiocarcinoma

Aims and background

Differential diagnosis of hepatocellular carcinoma and intrahepatic cholangiocarcinoma is sometimes difficult to accurately perform.

Methods

Eight markers including cytokeratin 7 (CK7), cytokeratin 19 (CK19), MOC31, CD10, glypican 3 (GPC3), claudin 4, biglycan and high mobility group A1 (HMGA1) were immunohistochemically stained in samples from 179 surgically resected hepatocellular carcinomas and 127 intrahepatic cholangiocarcinomas, and the rates of marker expression were statistically compared.

Results

With the exception of biglycan, 7 of the 8 markers were found to have significantly different expression patterns when comparing the two types of cancer (P <0.05). In intrahepatic cholangiocarcinomas, the expression rates of CK7, CK19, MOC31, claudin 4 and HMGA1 were 83.4%, 89.0%, 88.2%, 69.2%, and 31.5%, respectively. These rates of expression in intrahepatic cholangiocarcinomas were all higher than in those in hepatocellular carcinomas (CK7, 31.3%; CK19, 10.1%; MOC31, 34.0%; claudin 4, 11.2%; and HMGA1, 19.5%). The expression rates of GPC3, CD10, and biglycan were 72.6%, 39.7% and 10.0%, respectively, in hepatocellular carcinoma. These were higher than the rates found in intrahepatic cholangiocarcinomas (GPC3, 7.0%; CD10, 18.1%; and biglycan, 7.0%). In a multivariate logistic regression analysis, GPC3, CK19, MOC31 and claudin 4 were found to be independent markers for differentially diagnosing intrahepatic cholangiocarcinoma.

Conclusions

Based on our results, GPC3 and CK19 can be used as first-line markers for differential diagnoses of hepatocellular carcinoma and intrahepatic cholangiocarcinoma (accuracy rate, 73.5%), and additional combined screening for claudin 4 and MOC31 markers in GPC3(-) and CK19(-) tumors might increase the accuracy rate for distinguishing hepatocellular carcinoma from intrahepatic cholangiocarcinoma to 88.5%.

Intrahepatic mass-forming cholangiocarcinoma and solitary hypovascular liver metastases: is the differential diagnosis using diffusion-weighted MRI possible?

Background Intrahepatic mass-forming cholangiocellular carcinoma (IMC) is the second most common primary liver tumor. The differentiation between IMC and solitary hypovascular liver metastases (SHLM) represents a diagnostic challenge due to many overlapping magnetic resonance imaging (MRI) features. Purpose To determine the value of diffusion-weighted imaging (DWI) in addition to conventional MRI for the distinction between intrahepatic mass-forming cholangiocarcinoma and solitary hypovascular liver metastases. Material and Methods Fifty-three patients with pathologically proven IMC (n = 31) and SHLM (n = 22) who had undergone MRI and DWI before surgery or percutaneous biopsy were enrolled in this study. The following MRI features were analyzed: the size and shape of the lesion, presence of capsular retraction and segmental biliary dilatation, T2-weighted (T2W) signal intensity, the presence of target sign on DWI and enhancement pattern. Apparent diffusion coefficient (ADC) values were calculated for each lesion ( b = 800 s/mm²). Univariate and multivariate logistic regression analyses were used to identify significant differentiating features between IMCs and SHLMs. Results Univariate analysis revealed that following parameters favor diagnosis of IMCs over SHLMs: lobulating shape, heterogeneous T2W signal intensity, capsular retraction, segmental biliary dilatation, target sign on DWI and rim-like enhancement on arterial phase followed by progressive enhancement in delayed phases. ADC values measured in the periphery of the lesion were significantly lower in IMCs in comparison to SHLMs. Multivariate analysis revealed that target sign on DWI was the most significant predictor of IMCs. Conclusion Qualitative DWI analysis with target sign significantly improves diagnostic accuracy for differentiation among IMC and SHLM lesions.

Utility of KRAS mutational analysis in the preoperative diagnosis of synchronous pancreatic cancer and intrahepatic cholangiocarcinoma: A case report

RATIONALE

It is often challenging to discriminate between intrahepatic cholangiocarcinoma (ICC) and metastatic liver tumors, especially when the hepatic tumor is small and of a mass-forming type.

PATIENT CONCERNS

We report a 69-year-old woman presented at our hospital with a small solid tumor in the head of the pancreas that was previously discovered during a medical checkup.

DIAGNOSES

The patient was diagnosed with synchronous pancreatic cancer and ICC.

INTERVENTIONS

The patient underwent clinical, histological, immunohistological, and KRAS mutational analysis.

OUTCOMES

Computed tomography revealed poorly enhanced small nodules in both the pancreatic head and liver. Biopsies of both nodules revealed adenocarcinoma; however, it was unclear whether the hepatic lesion was a metastasis of the pancreatic tumor or primary ICC. KRAS mutational analysis from FFPE biopsy samples revealed a discordance of mutation status between the tumors. Therefore, the patient was diagnosed with synchronous pancreatic cancer and ICC, whereupon she underwent hepatopancreatoduodenectomy.

LESSONS

KRAS mutational analysis of FFPE biopsy samples can be utilized for differentiating between ICC and metastatic liver tumor.

Micrometastasis in colorectal cancer: does it affect staging?

BACKGROUND

Micrometastasis (MM) in colorectal cancer (CRC) is not considered in tumour-node-metastasis (TNM) staging currently and also the prognostic significance of these occult tumoural cells is not proven yet. This study was designed to find whether MM to bone marrow (BM) and/or liver cause upstaging of the tumour according to conventional staging system and if it may alter the survival rate.

METHODS

Thirty-eight CRC patients who were candidates of surgical procedure were enrolled in our cross-sectional study. Liver and BM biopsy were obtained during the surgery to be looked for tissue-specific marker of CRC, CK20. CK20 expression in BM and liver was assessed by the two methods of reverse transcriptase polymerase chain reaction and immunohistochemistry.

RESULTS

Among the 38 submitted patients, a total number of 14 MM, including 10 BM (23%) and seven hepatic (18%) were detected. There was no significant difference in clinicopathological aspects including size, location, stage, grade, local invasion to vessels and neurons, TNM staging and relapse rate of tumour among patients with/without disseminated tumoural cells. The result did not demonstrate a survival difference between patients receiving neoadjuvant chemotherapy compared to other patients.

CONCLUSION

Our study did not confirm that the presence of MM influences TNM staging and overall survival of the patients. Additional clinical investigations with longer follow-up period and larger number of cases are required to decide on administration of neoadjuvant therapy in CRC patients.

Practical Applications in Immunohistochemistry: Carcinomas of Unknown Primary Site

CONTEXT

-Identification of the site of origin of carcinoma of unknown primary using immunohistochemistry is a frequent requirement of anatomic pathologists. Diagnostic accuracy is crucial, particularly in the current era of targeted therapies and smaller sample sizes.

OBJECTIVES

-To provide practical guidance and suggestions for classifying carcinoma of unknown primary using both proven and new antibodies, as well as targeting panels based on integration of morphologic and clinical features.

DATA SOURCES

-Literature review, the authors' practice experience, and authors' research.

CONCLUSIONS

-With well-performed and interpreted immunohistochemistry panels, anatomic pathologists can successfully identify the site of origin of carcinoma of unknown primary. It is crucial to understand not only the diagnostic uses of the many available antibodies but also the potential limits and pitfalls.

Mass-forming cholangiocarcinoma and adenocarcinoma of unknown primary: can they be distinguished on liver MRI?

PURPOSE

To determine MR features suggestive of mass-forming cholangiocarcinoma (CCA) or liver metastases of adenocarcinoma of unknown primary (AUP), and to compare the ability of two experienced radiologists to establish the correct diagnosis.

MATERIALS AND METHODS

61 patients with CCA or AUP, with MRIs were placed into two groups: population 1, 28 patients with certain diagnosis of either CCA or AUP; and population 2, 33 patients with uncertain diagnosis. Using population 1 with known diagnosis, two investigators formulated imaging criteria for CCA or AUP, which represented phase 1 of the study. In phase 2, two independent radiologists categorized the patients in populations 1 and 2 as CCA or AUP using the formulated criteria. This categorization was compared with the patient medical records and pathologist review. Findings were tested for statistical significance.

RESULTS

In phase 1, solitary lesion, multifocal lesions with dominant lesion, capsule retraction, and porta hepatis lymphadenopathy were features of CCA; multifocal lesions with similar size, and ring enhancement were features of AUP. The number of lesions, capsule retraction, and early tumor enhancement pattern were observed to be significant features (P < 0.05). In phase 2, agreement between the two radiologists was good (k = 0.663). For population 1, the agreement was good (k = 0.659), and was fair for population 2 (k = 0.293). Concordance between the two radiologists, medical record, and the pathologist was found in 41/61 (67%) patients.

CONCLUSION

Distinctive features of CCA and AUP are identifiable on MRI images, which may aid the radiologist to establish the correct diagnosis.

Mass spectrometry-based proteomic analysis of formalin-fixed paraffin-embedded extrahepatic cholangiocarcinoma

BACKGROUND

Extrahepatic cholangiocarcinoma is very difficult to diagnose at an early stage, and has a poor prognosis. Novel markers for diagnosis and optimal treatment selection are needed. However, there has been very limited data on the proteome profile of extrahepatic cholangiocarcinoma. This study was designed to unravel the proteome profile of this disease and to identify overexpressed proteins using mass spectrometry-based proteomic approaches.

METHODS

We analyzed a discovery set of formalin-fixed paraffin-embedded tissues of 14 extrahepatic cholangiocarcinomas using shotgun mass spectrometry, and compared proteome profiles with those of seven controls. Then, selected candidates were verified by quantitative analysis using scheduled selected reaction monitoring-based mass spectrometry. Furthermore, immunohistochemical staining used a validation set of 165 cases.

RESULTS

In total, 1,992 proteins were identified and 136 proteins were overexpressed. Verification of 58 selected proteins by quantitative analysis revealed 11 overexpressed proteins. Immunohistochemical validation for 10 proteins showed positive rates of S100P (84%), CEAM5 (75%), MUC5A (62%), OLFM4 (60%), OAT (42%), CAD17 (41%), FABPL (38%), AOFA (30%), K1C20 (25%) and CPSM (22%) in extrahepatic cholangiocarcinomas, which were rarely positive in controls.

CONCLUSIONS

We identified 10 proteins associated with extrahepatic cholangiocarcinoma using proteomic approaches. These proteins are potential targets for future diagnostic biomarkers and therapy.

Tubulin β-III: a novel immunohistochemical marker for intrahepatic peripheral cholangiocarcinoma

AIMS

Our recent proteomic study identified tubulin β-III (TUBB3) as a potential tissue marker for intrahepatic cholangiocarcinomas (CCs). This validation study was conducted to see whether or not TUBB3 can serve as a novel immunohistochemical marker for peripheral CCs, using a large cohort (n = 197) covering various liver tumours and premalignant conditions.

METHODS AND RESULTS

Immunostaining using a monoclonal antibody demonstrated TUBB3 expression in 14/28 cases of peripheral CCs (50%), while its expression was significantly less common in perihilar CCs (6/40, 15%) (P = 0.002). No significant difference was identified in clinicopathological features between TUBB3-positive and -negative cases. TUBB3 expression was entirely negative in hepatocellular carcinomas, biliary premalignant lesions (i.e., biliary intraepithelial neoplasias, intraductal papillary neoplasms), peribiliary gland hamartomas (bile duct adenomas), and non-neoplastic biliary epithelium. TUBB3 expression was only focally noted in 2/12 cases of mixed hepatocellular and cholangiocarcinomas (<10% of cancer cells). Compared with other biliary (CK7 and CK19) and malignant markers (p53 and MUC1), TUBB3 was less sensitive but more specific for peripheral CCs. TUBB3 was also expressed in 40% of metastatic colorectal or breast cancers.

CONCLUSIONS

This study revealed that TUBB3 is a moderately sensitive and highly specific tissue marker for discriminating peripheral CCs from other primary liver tumours.

Differences in immunohistochemical biomarkers between intra- and extrahepatic cholangiocarcinoma: a systematic review and meta-analysis

BACKGROUND AND AIM

Cholangiocarcinomas of different locations differ in growth patterns, symptoms, treatment response, and survival. Still, they are regarded in many studies as a uniform malignancy. Because intra- (iCCA) and extrahepatic (eCCA) cholangiocarcinoma display such differences, we performed a systematic review and meta-analysis to analyze differences in the immunohistochemical profile of these tumors.

METHODS

In February 2014, we searched the two main medical literature databases MEDLINE and EMBASE. We extracted risk ratios and 95% confidence intervals from the identified studies and performed random-effects model meta-analyses in accordance with PRISMA and REMARK guidelines.

RESULTS

A total of 54 cohort studies, including 4458 patients and studying 102 individual markers met the inclusion criteria. Of the 57 markers that were evaluated in more than 30 iCCA and eCCA patients, 18 showed a statistically significant difference in expression between iCCA and eCCA. Biomarkers expressed differently between iCCA and eCCA included potential targets of therapy: EGFR, c-erbB-2 and VEGF-A. Several markers showed no statistical difference but large 95% confidence intervals, suggesting insufficient sample size.

CONCLUSIONS

This systematic review shows differences in marker expression between iCCA and eCCA. Consequently, patients with iCCA and eCCA may benefit from different treatment strategies.

Cocarcinogenic effects of intrahepatic bile acid accumulation in cholangiocarcinoma development

Bile acid accumulation in liver with cholangiolar neoplastic lesions may occur before cholestasis is clinically detected. Whether this favors intrahepatic cholangiocarcinoma development has been investigated in this study. The E. coli RecA gene promoter was cloned upstream from Luc2 to detect in vitro direct genotoxic ability by activation of SOS genes. This assay demonstrated that bile acids were not able to induce DNA damage. The genotoxic effect of the DNA-damaging agent cisplatin was neither enhanced nor hindered by the hepatotoxic and hepatoprotective glycochenodeoxycholic and glycoursodeoxycholic acids, respectively. In contrast, thioacetamide metabolites, but not thioacetamide itself, induced DNA damage. Thus, thioacetamide was used to induce liver cancer in rats, which resulted in visible tumors after 30 weeks. The effect of bile acid accumulation on initial carcinogenesis phase (8 weeks) was investigated in bile duct ligated (BDL) animals. Serum bile acid measurement and determination of liver-specific healthy and tumor markers revealed that early thioacetamide treatment induced hypercholanemia together with upregulation of the tumor marker Neu in bile ducts, which were enhanced by BDL. Bile acid accumulation was associated with increased expression of interleukin (IL)-6 and downregulation of farnesoid X receptor (FXR). Bile duct proliferation and apoptosis activation, with inverse pattern (BDL > thioacetamide + BDL >> thioacetamide vs. thioacetamide > thioacetamide + BDL > BDL), were observed. In conclusion, intrahepatic accumulation of bile acids does not induce carcinogenesis directly but facilitates a cocarcinogenic effect due to stimulation of bile duct proliferation, enhanced inflammation, and reduction in FXR-dependent chemoprotection.

IMPLICATIONS

This study reveals that bile acids foster cocarcinogenic events that impact cholangiocarcinoma.

Detection of circulating tumor cells in cancers of biliary origin

BACKGROUND

Circulating Tumor Cells (CTCs) have been described in malignancies of epithelial origin. In this study we examined the detection of CTCs using CellSearch assay in cholangiocarcinoma and gallbladder cancer.

METHODS

The clinical outcomes and detection of CTCs were examined in sixteen patients with biliary cancer using the CellSearch assay. Stages of cancer, baseline demographic data and overall survival were evaluated.

RESULTS

Thirteen patients had cholangiocarcinoma and three had gallbladder cancer. Using a cut off of two or more CTCs per 7.5 mL of blood, 3/13 cholangiocarcinoma and 1/3 gallbladder cancer patients had detectable CTCs. At 12 months of follow up from time CTC is drawn; 1/4(25%) of patients with positive CTC were alive while 6/12 (50%) of patients with negative CTC remained alive without a significant difference in survival between the two groups.

CONCLUSIONS

Our finding that 25% of patients with cholangiocarcinoma and gallbladder cancer have two or more detectable CTCs/7.5 mL is the first report to our knowledge in this disease. Larger patient numbers are needed to determine the prognostic significance of finding CTCs in biliary cancer. Prospective validation of the role of CTC in advanced biliary cancer patients is on going.

Two distinct pathways of carcinogenesis in primary sclerosing cholangitis

AIMS

To identify clinicopathological characteristics of cholangiocarcinoma and premalignant lesions arising in patients with primary sclerosing cholangitis (PSC).

METHODS AND RESULTS

This study consisted of 25 patients with PSC and bile duct neoplasia [16 with cholangiocarcinoma and nine with biliary intra-epithelial neoplasia (BilIN) equivalent to biliary dysplasia]. Tumour cell morphology, growth patterns, history of inflammatory bowel disease and postoperative survival were recorded. Immunohistochemistry for CK7, CK20, MUC1, MUC2, MUC5AC, MUC6 and CDX2 was performed to characterize cell phenotypes. Cholangiocarcinoma and BilIN were classified into intestinal (n = 14) and non-intestinal classical (n = 11) types. Intestinal-type lesions showed histological features resembling intestinal dysplasia or adenocarcinoma. Intestinal-type cholangiocarcinoma commonly showed intraductal papillary proliferation and mucinous nodule formation. Intestinal-type lesions often had an intestinal immunophenotype that was not detected in classical-type lesions: CK20, 50% versus 0% (P = 0.007); MUC2, 86% versus 0% (P < 0.001); CDX2, 54% versus 0% (P = 0.003). Less commonly, intestinal-type cholangiocarcinoma showed perineural invasion (P = 0.003). Patients with intestinal-type cholangiocarcinoma had a more favourable cancer-specific prognosis than those with classical-type cholangiocarcinoma (P = 0.043).

CONCLUSIONS

Bile ducts in PSC show two distinct dysplasia-carcinoma sequences as evidenced by differences in cell morphology, growth patterns, immunophenotypes and grade of malignancy.

The novel monoclonal antibody HPC2 and N-cadherin distinguish pancreatic ductal adenocarcinoma from cholangiocarcinoma

Metastatic pancreatic ductal adenocarcinoma and primary cholangiocarcinoma are morphologically very similar and, therefore, challenging to distinguish in liver biopsies. The distinction is important because surgical management and prognosis differ significantly. Several immunohistochemical markers have been evaluated to aid this diagnosis, but aside from N-cadherin, which labels cholangiocarcinoma, few provide the combination of good sensitivity and specificity. Our laboratory recently developed the novel monoclonal antibody human pancreatic cancer fusion #2 (HPC2) that recognizes pancreatic cancer. We hypothesized that the combination of our new marker and N-cadherin can assist in distinguishing metastatic pancreatic cancer from cholangiocarcinoma. We immunostained resections of 60 pancreatic ductal adenocarcinomas and 31 cholangiocarcinomas for the HPC2 and N-cadherin antigens. We also stained 24 gallbladder adenocarcinomas, 11 ampullary adenocarcinomas, and 10 metastatic colonic adenocarcinomas to the liver. Sections were independently scored by 2 pathologists with good agreement using both markers (κ statistics, 0.62-0.64; P < .0001). HPC2 was observed in 80% of pancreatic cancers (48/60), 82% of ampullary (9/11), and 32% (10/31) of cholangiocarcinomas. N-cadherin stained 27% (16/60) of the pancreas cases and 58% (18/31) of the cholangiocarcinomas. Gallbladder and colon cancers were usually double negative (18/24 and 8/10, respectively). Each marker provided significant likelihood ratios to separate pancreatic cancer (HPC2, 2.48 [1.46-4.19]; P < .0001) from cholangiocarcinoma (N-cadherin, 2.17 [1.3-3.64]; P < .01). The combination of both markers provided even better specificity and positive likelihood ratios. We conclude that HPC2 and N-cadherin significantly improve accurate classification of pancreatic cancer and cholangiocarcinoma.

[Pathology of cholangiocarcinoma]

Cholangiocarcinomas (CC) are tumors that arise from the epithelial cell of the biliary tract. They represent the second most frequent primitive liver malignancy after hepatocellular carcinoma. Recent epidemiological data show an increase incidence of CC independently of the increased incidence of cirrhosis. According to their location in the biliary tract, we distinguish intrahepatic, hilar (Klastkin tumors) and extrahepatic CC. In literature, confusion exists around hilar CC that are included, according series, to intrahepatic or extrahepatic CC. However, hilar CC share common clinical, morphological and therapeutic features with extrahepatic CC. So, OMS classification of digestive tumors defined two groups of CC: intrahepatic or peripheral CC which develop from small intrahepatic biliary duct beyond the second segmentation, and extrahepatic CC comprising hilar CC and tumors from common hepatic bile duct. In this chapter, we will describe the different gross features and histological characteristic of CC and will detail the major histopronostic criteria of these tumors.

A case of intrahepatic clear cell cholangiocarcinoma

Intrahepatic clear cell cholangiocarcinoma is very rare - only 8 cases have been reported. A 56-year-old Japanese man with chronic hepatitis B infection was diagnosed with a 2.2 cm hepatocellular carcinoma on imaging, and hepatic segmentectomy was performed. Histopathologically, the tumor cells had copious clear cytoplasm and formed glandular structures or solid nests. These pathological findings suggested the tumor was a clear cell variant of intrahepatic cholangiocarcinoma. Particular stains and radiological images suggested that the cause of the clear cell change had been glycogen, not mucin nor lipid. On immunohistochemical staining, cytokeratin (CK) 7 and CK19 were positive, whereas CK20 was negative. Vimentin was detected on the cell membranes, and CD56 was focally positive. The patient was given adjuvant chemotherapy and is currently free from the tumor 7 mo postoperatively. Careful follow-up with adequate postoperative supplementary chemotherapy is necessary because the characteristics of this type of tumor are unknown.

The use of Cytokeratin 19 (CK19) immunohistochemistry in lesions of the pancreas, gastrointestinal tract, and liver

Cytokeratin immunostaining forms the bedrock of the immunohistochemical evaluation of tumors. Cytokeratin 19 (CK19) belongs to a family of keratins, which are normally expressed in the lining of the gastroenteropancreatic and hepatobiliary tracts. CK19 immunohistochemistry has been used successfully in thyroid tumors to recognize papillary carcinomas for some time. However, its use in the pancreas, liver, and gastrointestinal tract (GIT) has only recently come to the fore. The purpose of this review is to look at the use of CK19 immunohistochemistry in tumors occurring at these sites. CK19 has been shown to be an independent prognostic factor for pancreatic neuroendocrine tumors, especially the insulin-negative tumors. CK19 positive tumors are associated with poor outcome irrespective of the established pathologic parameters such as size, mitoses, lymphovascular invasion, and necrosis. It is recommended that CK19 be part of the immunohistochemical panel in the work-up of pancreatic endocrine tumors. CK19 is positive in the most of neuroendocrine tumors occurring in the rest of the GIT, except rectal tumors, which are negative. In the liver, CK19 is of prognostic value in hepatocellular carcinomas and is of use in distinguishing cholangiocarcinoma from hepatocellular carcinomas. It can also be used to highlight native ductules in the liver and helps separate conditions such as focal nodular hyperplasia from hepatic adenoma. The vast majority of adenocarcinomas in the GIT and pancreas are CK19 positive.

Liver metastasis with intraductal invasion originating from rectal cancer: report of a case

We report a case of liver metastasis with intraductal invasion from colorectal cancer. The patient underwent abdominoperineal resection of the rectum for rectal cancer, and a computed tomography (CT) scan, done 4 years later, revealed a low-density lobular mass in the left lobe of the liver, with a tumor embolus in the second branch of the left bile duct (B2). Because the preoperative imaging findings showed an intraductal growth pattern, we performed a left lobectomy of the liver for intrahepatic cholangiocarcinoma (IHCC). Immunohistochemically, the carcinoma cells, including the intraductal growth, were focally positive for Cytokeratin (CK) 20, but negative for CK 7. This CK staining pattern suggested that the liver tumor was a metastasis from the previously resected rectal cancer. Thus, metastases from colorectal cancer can involve intraductal growth.

Liver fibrosis

Liver damage leads to an inflammatory response and to the activation and proliferation of mesenchymal cell populations within the liver which remodel the extracellular matrix as part of an orchestrated wound-healing response. Chronic damage results in a progressive accumulation of scarring proteins (fibrosis) that, with increasing severity, alters tissue structure and function, leading to cirrhosis and liver failure. Efforts to modulate the fibrogenesis process have focused on understanding the biology of the heterogeneous liver fibroblast populations. The fibroblasts are derived from sources within and out with the liver. Fibroblasts expressing alpha-smooth muscle actin (myofibroblasts) may be derived from the transdifferentiation of quiescent hepatic stellate cells. Other fibroblasts emerge from the portal tracts within the liver. At least a proportion of these cells in diseased liver originate from the bone marrow. In addition, fibrogenic fibroblasts may also be generated through liver epithelial (hepatocyte and biliary epithelial cell)-mesenchymal transition. Whatever their origin, it is clear that fibrogenic fibroblast activity is sensitive to (and may be active in) the cytokine and chemokine profiles of liver-resident leucocytes such as macrophages. They may also be a component driving the regeneration of tissue. Understanding the complex intercellular interactions regulating liver fibrogenesis is of increasing importance in view of predicted increases in chronic liver disease and the current paucity of effective therapies.

Pathology of peripheral intrahepatic cholangiocarcinoma with reference to tumorigenesis

Cholangiocarcinomas (CCs) are neoplasms with cholangiocyte differentiation, and may arise from cholangiocytes of the biliary tree and possibly cholangiocyte progenitor cells. Intrahepatic CCs can be divided into the perihilar and peripheral types. Peripheral CCs present grossly as a mass forming tumor, and histologically as an adenocarcinoma of varying shapes and phenotypes. Some peripheral CCs (ductular type) are characterized by: (i) a histological resemblance to reactive bile ductules; (ii) the expression of neural cell adhesion molecule (NCAM) and vimentin. This type shows: (i) grossly, a blurred border; and (ii) histologically, carcinoma cells replacing the adjoining hepatocytes at the border of the tumor. It is frequently associated with neutrophilic infiltration and also with granulocyte and granulocyte macrophage colony-stimulating factors. We propose to call this type "ductular CC." The other peripheral CC (duct type) includes ordinary adenocarcinoma with well to moderately differentiated tubular and micropapillary patterns and is negative for NCAM but positive for mucin. This type can be called "duct CC," and shows a rather compressive growth. Interestingly, CC components of combined hepatocellular CC share the features of ductular CC, suggesting that hepatic progenitor cells may be involved in the tumorigenesis of ductular CC. The biological behavior of ductular CC and duct CC remains obscure, and follow-up and molecular studies on these tumors are required in order for these two CCs to be recognized as disease entities, and so as to evaluate their carcinogenesis.

Circulating markers of biliary malignancy: opportunities in proteomics?

Cholangiocarcinoma, a primary liver tumour that arises from biliary epithelial cells, is increasing in incidence and has poor prognosis. Diagnosis is difficult, particularly in patients with primary sclerosing cholangitis, who are at risk of developing the disease. Timely diagnosis is essential because surgical resection in early disease remains the only cure. The lack of a sensitive and specific early diagnostic marker and of alternative treatments are the main reasons why patients have limited survival. The use of proteomic-based approaches, which analyse the physiological or pathological complement of proteins (ie, the proteome) in cells, tissues, or biological fluids, has received substantial interest in biomarker discovery. Proteomics complements genomic studies and examines functional end-units quantitatively and qualitatively, including post-translational modifications which might vary with disease and might have key roles in protein function or localisation. Major advances in technology and bioinformatics have enhanced proteomic studies, resulting in increased understanding of the pathogenesis of many diseases and in biomarker discovery with effective use of tissues, cell lines, and biological fluids. We review the current status and promise of proteomic-based approaches in biomarker discovery for cholangiocarcinoma.

Intrahepatic Clear Cell Cholangiocarcinoma

Clear cell cholangiocarcinoma is a very unusual variant of peripheral bile duct carcinoma. We present 3 cases on which we performed a broad spectrum of immunohistochemical analysis. The tumors showed a glandular and trabecular growth pattern with abundant desmoplastic stroma and clear cell change of about 80% of the tumor cells. Positive expression of CK7 indicated a cholangiocellular origin. A primary hepatocellular carcinoma and metastatic clear cell tumors of the kidney, gastrointestinal tract, and the thyroid gland were excluded by absence of CK20, CD10, HepPar1, and TTF1. No mucin could be detected within the cytoplasm of the clear cells. Electronmicroscopy revealed only a few glycogen granula, but numerous cytoplasmic lipoid vacuoles as a possible explanation for the clear cell phenotype. All 3 tumors exhibited positive expression of CD56 (NCAM) in a significant amount of the clear cells. Beside the clear cell component, one tumor also showed an adenocarcinomalike and a well-differentiated tubular component. CD56 expression was detected in all 3 tumor areas. This report of 3 cases demonstrates that clear cell cholangiocarcinomas are not only of unusual histomorphology. They also show CD56 expression which is a very uncommon finding for intrahepatic cholangiocarcinomas. As CD56 expression is also found in reactive bile ducts and bile duct adenomas, one may speculate that these rare neoplasms may originate from reactive bile ducts or cholangiomatous lesions.

Cell-surface associated p43/endothelial-monocyte-activating-polypeptide-II in hepatocellular carcinoma cells induces apoptosis in T-lymphocytes

OBJECTIVE

The novel, proinflammatory cytokine endothelial-monocyte-activating-polypeptide-II (EMAP-II) was first found in tumour cell supernatants and is closely related or identical to the p43 component of the mammalian multisynthetase complex. In its secreted form, EMAP-II has multiple cytokine-like activities in vitro, including chemotactic, procoagulant and antiangiogenic properties. We recently showed that neoplastic but not normal hepatocytes expresses the 34-kDa molecule on the cell surface in vitro and the cell-surface expression is upregulated by treatment with tumour necrosis factor (TNF)-alpha/interferon (IFN)-gamma and/or hypoxia. We hypothesized an immune-regulatory role of EMAP-II within neoplastic tissues and investigated its effects on lymphocytes.

METHODS

To study the role of EMAP-II in tumour cell-induced lymphocyte killing, Jurkat T-cells were co-cultured with a range of hepatocellular carcinoma (HCC) cell monolayers (HuH-7, HepG2 and Alexander cells), which were either untreated or treated with TNF-alpha/IFN-gamma under normoxic and hypoxic conditions over a period of 16-24 hours. Flow cytometric analysis of apoptosis in Jurkat cells was performed using the annexin-V-FITC/propidium iodide technique.

RESULTS

rEMAP-II caused a dose-dependent apoptosis in Jurkat T-cells. Co-culture of Jurkat cells with HCC cell monolayers induced significant apoptosis of the Jurkat cells. In general, under normoxic conditions, cytokine-treated HCC cell monolayer caused more apoptosis than untreated cells. This effect was enhanced by hypoxia. Critically, native EMAP-II expressed on the surface of the HCC cells also induced activation of caspase-8 and apoptosis in Jurkat cells, which was partially but significantly blocked by addition of polyclonal antibodies against EMAP-II to the incubation mixture.

CONCLUSION

Our data suggest that membrane-bound EMAP-II is cytotoxic to lymphocytes and, therefore, might constitute a component of a novel, immunosuppressive pathway by which HCC cells may eliminate attacking T-cells and evade the immune system. The mechanism by which it does so is currently under investigation.

Gemcitabine in advanced biliary tract cancers

The annual incidence of hepatobiliary cancer has been steadily increasing in the USA from 15,000 in 1993 to 22,200 in 2000. Despite this increase, it still continues to be a rare neoplasm. Surgical resection is the treatment of choice, but a high percentage of patients are unsuitable for resection. These patients have a very poor prognosis because of the lack of efficacious therapy options. Thus, overall survival in these patients ranges from 3 to 12 months, depending on the extent of disease and its site of origin. For some time, mitomycin C, doxorubicin and 5-fluorouracil have been considered among the most active chemotherapeutic agents, with a response rate ranging from 10 to 20%. More recently, gemcitabine has become the reference agent for these neoplasias because of the histologically common origin of biliary cancer and exocrine pancreatic cancer. However, its role has yet to be well-defined. Here we examine clinical trials designed for locally advanced and metastatic biliary tract cancer and review the existing data supporting palliative therapy with gemcitabine alone or in association with other drugs.

Bedeutung der Immunhistochemie für die Diagnose des Cholangiokarzinoms

The correct diagnosis of intrahepatic cholangiocarcinoma (CC) is often confounded by the small size of the diagnostic specimen and the wide morphological range of carcinomas metastasising to the liver. Expression analysis of cytokeratins, glycoproteins, mucoproteins, adhesion molecules, receptors and transcription factors has been shown to be a valuable adjunct in the typing of carcinomas. For this study, the expression pattern of 30 well documented antibodies to CC and the most common metastatic adenocarcinomas of the liver were studied. CC show a rather distinct immunophenotype with co-expression of CK7, CK17, CD7 and a lack of CDX2. Although this pattern allows the separation of CC from most metastatic carcinomas, pancreatic carcinomas show a broad overlap with this expression pattern.

Liver fluke-associated and sporadic cholangiocarcinoma: an immunohistochemical study of bile duct, peribiliary gland and tumour cell phenotypes

AIM

To compare cell phenotypes displayed by cholangiocarcinomas and adjacent bile duct lesions in patients from an area endemic in liver-fluke infestation and those with sporadic cholangiocarcinoma.

METHODS

65 fluke-associated and 47 sporadic cholangiocarcinomas and 6 normal livers were studied. Serial paraffin-wax sections were stained immunohistochemically with monoclonal antibodies characterising a Brunner or pyloric gland metaplasia cell phenotype (antigens D10 and 1F6), intestinal goblet cells (antigen 17NM), gastric foveolar apomucin (MUC5AC), a gastrointestinal epithelium cytokeratin (CK20) and the p53 protein.

RESULTS

60% of the 112 cholangiocarcinomas expressed antigen D10, 68% MUC5AC, 33% antigen 17NM and 20% CK20; 37% showed overexpression of p53. When present together in a cholangiocarcinoma, cancer cells expressing D10 were distinct from those displaying 17NM or MUC5AC. Many more fluke-associated cholangiocarcinomas than sporadic cholangiocarcinomas displayed 17NM and p53 expression. Most cases of hyperplastic and dysplastic biliary epithelium expressed D10 strongly. Pyloric gland metaplasia and peribiliary glands displayed D10 and 1F6, with peribiliary gland hyperplasia more evident in the livers with fluke-associated cholangiocarcinoma; goblet cells in intestinal metaplasia stained for 17NM. No notable association of expression between any two antigens (including p53) was found in the cancers.

CONCLUSIONS

Most cases of dysplastic biliary epithelium and cholangiocarcinoma display a Brunner or pyloric gland cell phenotype and a gastric foveolar cell phenotype. The expression of D10 in hyperplastic and dysplastic epithelium and in cholangiocarcinoma is consistent with a dysplasia-carcinoma sequence. Many more fluke-associated cholangiocarcinomas than sporadic cholangiocarcinoma display an intestinal goblet cell phenotype and overexpress p53, indicating differences in the aetiopathology of the cancers in the two groups of patients.

Metastatic colon cancer from intrahepatic cholangiocarcinoma

A 62-year-old man had been followed because of an elevated serum level of carcinoembryonic antigen without the detection of any cancer lesions. However, there was a sudden increase in the serum level of carcinoembryonic antigen, and abdominal imagings showed a hepatic tumor with peripheral intrahepatic bile duct dilatation, and a submucosal tumor at the sigmoid colon with intact mucosa. Histopathological findings showed that the hepatic tumor had perineural invasion, suggesting an intrahepatic cholangiocarcinoma, and that the colon tumor infiltrated the submucosa, while its mucosa was intact. Both tumors showed similar pathological features and were positive for cytokeratin 20 and 7. These findings suggested intrahepatic cholangiocarcinoma with metastatic sigmoid colon cancer.

Liver cell lines for the study of hepatocyte functions and immunological response

BACKGROUND

Liver cell lines closely resembling primary hepatocyte are essential for research on hepatitis viruses and hepatocyte function. Currently used cell lines are derived from hepatic tumours and have altered gene expression.

AIMS

The generation and characterisation of novel human hepatocyte lines (HHLs) derived from healthy human liver, retaining the primary hepatocyte phenotype.

RESULTS

Primary hepatocytes were immortalised with Moloney's mouse leukaemia virus expressing E6 and E7 proteins of human papillomavirus, and cultures propagated long-term. All HHLs contained markers of hepatocyte and biliary phenotype (cytokeratins 7, 8, 18 and 19), Cytochrome P450 and albumin. The HHLs did not express high levels of p53 or alpha-fetoprotein. When grown in a collagen sandwich culture, or at the air-liquid interface, HHLs were maintained as monolayer whereas Huh-7 and HepG2 formed thick layers. All HHLs showed increased capacity to bind recombinant hepatitis C virus-like particles in comparison with Huh-7 and HepG2. We also demonstrate that HHLs contained active gap junctions, and that the cells respond to stimulation with IFN-alpha by upregulation of major histocompatibility complex (MHC)-I and -II.

CONCLUSIONS

These HHLs retain primary hepatocyte phenotype and should be useful for investigating mechanisms of entry and replication of hepatotropic viruses, and should also be valuable in the study of hepatocyte biology and pathology.

Gemcitabine combined with oxaliplatin (GEMOX) in advanced biliary tract adenocarcinoma: a GERCOR study

BACKGROUND

Since gemcitabine-oxaliplatin (GEMOX) has been used in pancreatic adenocarcinoma, we studied its activity and tolerability in advanced biliary tract adenocarcinoma (ABTA).

PATIENTS AND METHODS

Consecutive adult patients with confirmed ABTA were recruited from four centers. Those in group A had performance status (PS) 0-2, bilirubin <2.5x normal and received GEMOX as first-line chemotherapy. Those in group B had PS >2 and/or bilirubin >2.5x normal and/or prior chemotherapy. All received gemcitabine 1000 mg/m2 as a 10 mg/m2/min infusion on day 1, followed by oxaliplatin 100 mg/m2 as a 2-h infusion on day 2, every 2 weeks.

RESULTS

Tumor sites were gallbladder (19), extrahepatic bile ducts (5), ampulla of vater (3) and intrahepatic bile ducts (29). Results for group A (n = 3) were: objective response 36% [95% confidence interval (CI) 18.7% to 52.3%], stable disease 26%, progressive disease 39%, median progression-free survival (PFS) 5.7 months and overall survival (OS) 15.4 months. Results for group B (n = 23) were: objective response 22% (95% CI 6.5% to 37.4%), stable disease 30%, progressive disease 48%, PFS 3.9 months and OS 7.6 months. National Cancer Institute Common Toxicity Criteria grade 3-4 toxicities were neutropenia 14% of patients, thrombocytopenia 9%, nausea/vomiting 5% and peripheral neuropathy 7%.

CONCLUSION

The GEMOX combination is active and well tolerated in ABTA.

Subcellular localization of the ABCG2 transporter in normal and malignant human gallbladder epithelium

Epithelium of the gallbladder and biliary tract is exposed to high concentrations of potentially harmful exogenous and endogenous compounds excreted into primary bile. As the ATP-dependent efflux pump ABCG2 can prevent cellular accumulation of anticancer drugs, estrogen sulfate, xenobiotics, porphyrins, and sterols, its expression in the biliary tract might mediate protection by hindering their penetration. We therefore investigated the expression and subcellular distribution of ABCG2 in normal and malignant human gallbladder. After demonstrating ABCG2 expression in gallbladder epithelium by RT-PCR and Western blotting, we analyzed the subcellular localization of ABCG2 by indirect immunofluorescence in gallbladder adenocarcinoma specimens, and compared it to that in cholelithiasis, and normal gallbladder samples (n = 54). In control, cholelithiasis, and well-differentiated tumor samples (grade 1, T1-3), ABCG2 is present at the luminal membrane of epithelial cells, which was proven by colocalization of apical-bound TRITC-labeled lectin (wheat germ agglutinin). In poorly differentiated gallbladder adenocarcinomas, intracellular ABCG2, in addition to luminal ABCG2 immunoreactivity, was found in 13/21 carcinoma samples (grade 2 and 3, T2-4, P < 0.01). In 3/11 of grade 3 tumors, ABCG2 was present in the cytoplasmatic compartment only (P < 0.01). In proliferating bile ducts of cholangiocarcinomas, ABCG2 showed an analogous staining pattern with presence in cytosolic compartments. However, the apical marker enzyme neutral endopeptidase remained on the membrane in all samples. To study whether phosphatidylinositol 3-kinase (PI3K) signaling might be necessary for ABCG2 membrane insertion, we treated freshly isolated human gallbladder epithelial cells with the PI3K inhibitor wortmannin. As assessed by indirect immunofluorescence, this maneuver redistributes ABCG2 to intracellular compartments. In conclusion, our data suggest a protective role for ABCG2 in well-differentiated gallbladder epithelial cells. Cytoplasmatic accumulation of ABCG2 in poorly differentiated carcinomas might coincide with malfunctioning of PI3K-signaling pathways during tumor progression.

Liver metastasis from rectal cancer with prominent intrabile duct growth

Intrabiliary growth of liver metastases from colorectal cancer has rarely been studied. A surgically resected case of a metastatic liver tumor with prominent intrabiliary growth derived from rectal cancer is reported. The patient was a 62-year-old man who had received a low anterior resection for rectal cancer in March 2000. He was re-admitted due to obstructive jaundice in January 2003, and was diagnosed with hepatic malignancy in segment II of the liver with an intrabiliary tumor extending from the intrahepatic bile duct of segment II to the common hepatic duct. He underwent a left hepatectomy, a partial resection of segment VI, and an extrahepatic bile duct resection with reconstruction of the biliary tract. In the resected specimen, there were whitish tumors of 3 cm and 1.5 cm in diameter in segments II and VI, respectively, and an intrabiliary tumor originating from the main tumor in segment II extended to the common hepatic duct. Both the liver tumors and the intrabiliary tumor consisted of a well- to moderately differentiated adenocarcinoma, which showed the same histological features as the rectal cancer. The immunohistochemical findings strongly supported that these tumors, including the intrabiliary growth, were liver metastasis from the rectal cancer. The intrabiliary invasion and growth of metastatic liver tumors has generally been overlooked, notwithstanding their frequently observed biological behavior. The present case is informative, and further investigation into this type of metastatic liver tumor may be warranted.

Identification of differentially expressed genes in isogenic highly metastatic and poorly metastatic cell lines of R3230AC rat mammary adenocarcinoma

Tumour metastasis occurs as a result of a cascade of events including alterations in the expression of various genes. The identification of such genes is essential to understanding formation of metastasis. In a previous study, highly metastatic (LN4.D6) and poorly metastatic (CAb.D5) cell lines were obtained from the rat mammary adenocarcinoma cell line R3230AC. Subtractive hybridization was used to identify differentially expressed genes between these two cell lines. We identified eight cDNA clones in CAb.D5 and six cDNA clones in LN4.D6 that were differentially expressed. One of the cDNA clones in each cell line had no homology with known sequences. Expression patterns of these differentially expressed genes were examined in a pair of rat mammary and prostate adenocarcinoma cell lines. Compared with cell lines examined, cDNA FF-10 was only expressed in CAb.D5; however, cDNA RB-8, RE-1, RF-5 were only expressed in the highly metastatic LN4.D6. No correlation was observed between expression patterns of the differentially expressed genes and metastatic potential of these cells. However, differential expression of genes, especially cytokeratins (CK8 and CK5) and collagens (III and IV) between highly metastatic and low metastatic rat mammary adenocarcinoma cell lines might initiate further investigation of these genes in metastatic process.