Immunohistochemical Typing of Adenocarcinomas of the Pancreatobiliary System Improves Diagnosis and Prognostic Stratification

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.

Cholangiocarcinoma: Pathologic and Molecular Classification in the Era of Precision Medicine

CONTEXT.—

Cholangiocarcinoma (CCA) is a heterogeneous cancer of the bile duct, and its diagnosis is often challenging.

OBJECTIVE.—

To provide insights into state-of-the-art approaches for the diagnosis of CCA.

DATA SOURCES.—

Literature review via PubMed search and authors' experiences.

CONCLUSIONS.—

CCA can be categorized as intrahepatic or extrahepatic. Intrahepatic CCA is further classified into small-duct-type and large-duct-type, whereas extrahepatic CCA is classified into distal and perihilar according to site of origin within the extrahepatic biliary tree. Tumor growth patterns include mass forming, periductal infiltrating, and intraductal tumors. The clinical diagnosis of CCA is challenging and usually occurs at an advanced tumor stage. Pathologic diagnosis is made difficult by tumor inaccessibility and challenges in distinguishing CCA from metastatic adenocarcinoma to the liver. Immunohistochemical stains can assist in differentiating CCA from other malignancies, such as hepatocellular carcinoma, but no distinctive CCA-specific immunohistochemical profile has been identified. Recent advances in next-generation sequencing-based high-throughput assays have identified distinct genomic profiles of CCA subtypes, including genomic alterations that are susceptible to targeted therapies or immune checkpoint inhibitors. Detailed histopathologic and molecular evaluations of CCA by pathologists are critical for correct diagnosis, subclassification, therapeutic decision-making, and prognostication. The first step toward achieving these goals is to acquire a detailed understanding of the histologic and genetic subtypes of this heterogeneous tumor group. Here, we review state-of-the-art approaches that should be applied to establish a diagnosis of CCA, including clinical presentation, histopathology, staging, and the practical use of genetic testing methodologies.

Bile Duct Tumor as the Presenting Manifestation of Colon Cancer: A Case Report

Painless obstructive jaundice is a well-recognized clinical sign of hepatocellular pathology or obstruction of the biliary system. Bile duct tumors are a known etiology of painless obstructive jaundice. Here, we present a case of obstructive jaundice, which was initially thought be caused by cholangiocarcinoma based on computerized tomography imaging and endoscopic retrograde cholangiopancreatography but was later found to be hilar metastasis from an undiscovered colon cancer.

Challenges in Diagnosing and Reporting Cholangiocarcinoma

Intrahepatic cholangiocarcinoma is a challenge to the practicing surgical pathologist for several reasons. It is rare in many parts of the world, and thus practical exposure may be limited. Related to the fact of its rarity is the fact that more common tumors which frequently metastasize to the liver can be morphologically indistinguishable (eg, pancreatic ductal adenocarcinoma). Immunohistochemical testing is generally non-contributory in this context. Other difficulties arise from the protean morphologic manifestations of cholangiocarcinoma (ie, small duct vs. large duct) and the existence of combined cholangiocarcinoma and hepatocellular carcinoma. These, and other issues of concern to the practicing diagnostic pathologist are discussed herein.

Ampullary Cancer: Histological Subtypes, Markers, and Clinical Behaviour-State of the Art and Perspectives

There are different cancers in the peri-ampullary region, including pancreatic ductal adenocarcinoma (PDAC), duodenum cancers (DCs), and ampullary adenocarcinoma (AAC). Here, significant morphological-molecular characterizations should be necessary for the distinction of primary tumours and classifications of their subtypes of cancers. The sub classification of AACs might include up to five different variants, according to different points of view, concerning the prevalence of the two more-cellular components found in the ampulla. In particular, regarding the AACs, the most important subtypes are represented by the intestinal (INT) and the pancreato-biliary (PB) ones. The subtyping of AACs is essential for diagnosis, and their identifications have been impacting clinical management responses to treatments and overall survival (os) after surgery. Pb is associated with a worse clinical outcome. Otherwise, the criteria, through which are possible to attribute its subtype classification, are not well established. A triage of immune markers represented by CK7, CK20, and CDX-2 seem to represent the best compromise in order to split the cohort of AAC patients in the INT and PB groups. The test of choice for the sub-classification of AACs is represented by the immuno-histochemical approach, in which its molecular classification acquires its diagnostic, predictive, and prognostic value for both the INT and PB patients.

A Paradigm Shift in Primary Liver Cancer Therapy Utilizing Genomics, Molecular Biomarkers, and Artificial Intelligence

Primary liver cancer is the sixth most common cancer worldwide and the third leading cause of cancer-related death. Conventional therapies offer limited survival benefit despite improvements in locoregional liver-directed therapies, which highlights the underlying complexity of liver cancers. This review explores the latest research in primary liver cancer therapies, focusing on developments in genomics, molecular biomarkers, and artificial intelligence. Attention is also given to ongoing research and future directions of immunotherapy and locoregional therapies of primary liver cancers.

Pathological survey of precursor lesions in cholangiocarcinoma

BACKGROUND

To clarify the pathological significance of two precursors (high-grade biliary intraepithelial neoplasm [BilIN] and intraductal papillary neoplasm of bile duct [IPNB]) in cholangiocarcinomas (CCAs).

METHODS

Ninety-one cases of CCA (47 distal CCAs [dCCAs], 31 perihilar CCAs [pCCAs] and 13 intrahepatic CCAs of large duct type [LD-iCCAs]) were examined for their association with precursors. Neoplastic intraepithelial lesions without underlying infiltrating carcinoma in the surrounding mucosa of CCAs were considered to reflect high-grade BilIN. High-grade BilIN and IPNB were subdivided into gastric, biliary, intestinal and oncocytic subtypes, while CCAs were subdivided into gastrobiliary, intestinal and oncocytic subtypes. The postoperative overall survival (OS) was examined.

RESULTS

Fifty-four and 8 of 91 CCAs were associated with high-grade BilIN and IPNB, respectively, while these precursors were unidentifiable in the remaining CCAs. A majority of CCAs were of the gastrobiliary subtype, while the intestinal subtype was occasionally detected, and the oncocytic subtype was rare. CCAs with high-grade BilIN showed a similar postoperative OS to CCAs without precursors, while CCAs with IPNB showed a favorable postoperative OS compared to CCAs without precursors.

CONCLUSIONS

CCAs were frequently associated with precursors; high-grade BilIN may be a major precursor and IPNB a minor one. CCAs with IPNB showed a favorable postoperative OS compared to CCAs with high-grade BilIN.

The Emerging Role of Ferroptosis in Liver Cancers

Liver cancer represents a global health challenge with worldwide growth. Hepatocellular carcinoma (HCC) is the most common type of liver cancer. Indeed, approximately 90% of HCC cases have a low survival rate. Moreover, cholangiocarcinoma (CC) is another malignant solid tumor originating from cholangiocytes, the epithelial cells of the biliary system. It is the second-most common primary liver tumor, with an increasing course in morbidity and mortality. Tumor cells always show high metabolic levels, antioxidant modifications, and an increased iron uptake to maintain unlimited growth. In recent years, alterations in iron metabolism have been shown to play an important role in the pathogenesis of HCC. Several findings show that a diet rich in iron can enhance HCC risk. Hence, elevated iron concentration inside the cell may promote the development of HCC. Growing evidence sustains that activating ferroptosis may potentially block the proliferation of HCC cells. Even in CC, it has been shown that ferroptosis plays a crucial role in the treatment of tumors. Several data confirmed the inhibitory effect in cell growth of photodynamic therapy (PDT) that can induce reactive oxygen species (ROS) in CC, leading to an increase in malondialdehyde (MDA) and a decrease in intracellular glutathione (GSH). MDA and GSH depletion/modulation are crucial in inducing ferroptosis, suggesting that PDT may have the potential to induce this kind of cell death through these ways. A selective induction of programmed cell death in cancer cells is one of the main treatments for malignant tumors; thus, ferroptosis may represent a novel therapeutic strategy against HCC and CC.

Drug-induced tumor-specific cytotoxicity in a whole tissue ex vivo model of human pancreatic ductal adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is the most common type of pancreatic cancer. PDAC has a dismal prognosis and an inherent resistance to cytostatic drugs. The lack of reliable experimental models is a severe limitation for drug development targeting PDAC. We have employed a whole tissue ex vivo culture model to explore the effect of redox-modulation by sodium selenite on the viability and growth of PDAC. Drug-resistant tumors are more vulnerable to redox-active selenium compounds because of high metabolic activity and redox imbalance. Sodium selenite efficiently and specifically reduced PDAC cell viability (p <0.02) (n=8) and decreased viable de novo tumor cell outgrowth (p<0.05) while preserving non-neoplastic tissues. Major cellular responses (damaged tumor cells > 90%, tumor regression grades III-IV according to Evans) were observed for sodium selenite concentrations between 15-30 µM. Moreover, selenium levels used in this study were significantly below the previously reported maximum tolerated dose for humans. Transcriptome data analysis revealed decreased expression of genes known to drive PDAC growth and metastatic potential (CEMIP, DDR2, PLOD2, P4HA1) while the cell death-inducing genes (ATF3, ACHE) were significantly upregulated (p<0.0001). In conclusion, we report that sodium selenite has an extraordinary efficacy and specificity against drug-resistant pancreatic cancer in an organotypic slice culture model. Our ex vivo organotypic tissue slice culture model can be used to test a variety of drug candidates for swift and reliable drug responses to individual PDAC cases.

Clinical relevance of biomarkers in cholangiocarcinoma: critical revision and future directions

Cholangiocarcinoma (CCA) is a malignant tumour arising from the biliary system. In Europe, this tumour frequently presents as a sporadic cancer in patients without defined risk factors and is usually diagnosed at advanced stages with a consequent poor prognosis. Therefore, the identification of biomarkers represents an utmost need for patients with CCA. Numerous studies proposed a wide spectrum of biomarkers at tissue and molecular levels. With the present paper, a multidisciplinary group of experts within the European Network for the Study of Cholangiocarcinoma discusses the clinical role of tissue biomarkers and provides a selection based on their current relevance and potential applications in the framework of CCA. Recent advances are proposed by dividing biomarkers based on their potential role in diagnosis, prognosis and therapy response. Limitations of current biomarkers are also identified, together with specific promising areas (ie, artificial intelligence, patient-derived organoids, targeted therapy) where research should be focused to develop future biomarkers.

Pathological, molecular, and clinical characteristics of cholangiocarcinoma: A comprehensive review

Cholangiocarcinomas are a heterogeneous group of highly aggressive cancers that may arise anywhere within the biliary tree. There is a wide geographical variation with regards to its incidence, and risk-factor associations which may include liver fluke infection, primary sclerosing cholangitis, and hepatolithiasis amongst others. These tumours are classified into intrahepatic, perihilar and distal based on their anatomical location. Morphologically, intrahepatic cholangiocarcinomas are further sub-classified into small and large duct variants. Perihilar and distal cholangiocarcinomas are usually mucin-producing tubular adenocarcinomas. Cholangiocarcinomas develop through a multistep carcinogenesis and are preceded by dysplastic and in situ lesions. While clinical characteristics and management of these tumours have been extensively elucidated in literature, their ultra-structure and tumour biology remain relatively unknown. This review focuses on the current knowledge of pathological characteristics, molecular alterations of cholangiocarcinoma, and its precursor lesions (including biliary intraepithelial neoplasia, intraductal papillary neoplasms of the bile duct, intraductal tubulopapillary neoplasms and mucinous cystic neoplasm).

Isolated Ovarian Metastasis from Pancreatic Cancer Mimicking Primary Ovarian Neoplasia: Role of Molecular Analysis in Determining Diagnosis

Background and Presentation: In this study, we present the case of a 64-year-old female with a chief complaint of abdominal pain and bloating, which had been persistent over a period of 4 months. Imaging revealed a 6.1-cm left-sided pancreatic mass as well as a 19.1-cm multiloculated cystic lesion in the pelvis, later revealed to be replacing the left ovary. The pancreatic mass was biopsied through endoscopic ultrasound-guided fine needle aspiration, and diagnosed as adenocarcinoma by cytology. The patient was treated with neoadjuvant chemotherapy and radiation before laparotomy for resection of the pancreas and left adnexal mass. Her response to treatment was followed radiologically and biochemically with cancer antigen (CA) 19-9 (114–35 U/mL), carcinoembryonic antigen (12–4.8 ng/mL), and CA-125 (119–15.3 U/mL) levels. She subsequently underwent an Appleby procedure, and resection of left pelvic mass and bilateral oophorectomy. Permanent sections revealed residual pancreatic ductal carcinoma with treatment effect, and a multicystic epithelial neoplasia of the left ovary for which the differential was primary ovarian carcinoma versus metastatic disease.

Conclusions: Molecular mutational analysis was performed on sections of both the ovarian tumor and the pancreatic tumor to aid in diagnosis. The ovarian tumor in this case showed exactly the same mutations, KRAS G12R and TP53 G245S, as in the treated pancreatic cancer. This raised the high probability that these tumors originated from the same clonal event. The findings suggested that the ovarian tumor was an isolated metastasis of the pancreatic primary, despite the morphologic ambiguity between the two sites of neoplasia.

Stabilization of the classical phenotype upon integration of pancreatic cancer cells into the duodenal epithelium

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PDAC cells in the duodenal epithelium mimic intestinal cells and co-opt the basement membrane.

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Intramucosal PDAC location is strongly coupled to the classical phenotype and to intestinal traits.

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Intratumoral heterogeneity is linked to specific tissue compartments, which shape phenotype plasticity of PDAC cells.

Introduction

Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive solid tumors. Based on transcriptomic classifiers, basal-like and classical PDAC subtypes have been defined that differ in prognosis. Cells of both subtypes can coexist in individual tumors; however, the contribution of either clonal heterogeneity or microenvironmental cues to subtype heterogeneity is unclear. Here, we report the spatial tumor phenotype dynamics in a cohort of patients in whom PDAC infiltrated the duodenal wall, and identify the duodenal epithelium as a distinct PDAC microniche.

Materials and methods

We used serial multiplex quantitative immunohistochemistry (smq-IHC) for 24 proteins to phenotypically chart PDAC tumor cells in patients whose tumors infiltrated the duodenal epithelium. Additionally, we used a genetically engineered mouse model to study the PDAC cell phenotype in the small intestinal epithelium in a controlled genetic background.

Result

We show that pancreatic cancer cells revert to non-destructive growth upon integration into the duodenal epithelium, where they adopt traits of intestinal cell differentiation, associated with phenotypical stabilization of the classical subtype. The integrated tumor cells replace epithelial cells in an adenoma-like manner, as opposed to invasive growth in the submucosa. Finally, we show that this phenomenon is shared between species, by confirming duodenal integration and phenotypic switching in a genetic PDAC mouse model.

Discussion

Our results identify the duodenal epithelium as a distinct PDAC microniche and tightly link microenvironmental cue to cancer transcriptional subtypes. The phenomenon of “intestinal mimicry” provides a unique opportunity for the systematic investigation of microenvironmental influences on pancreatic cancer plasticity.

Annexin Expression in Cholangiocarcinoma, and Metastatic Pancreatic Ductal Adenocarcinoma "Is it be Helpful for Differential Diagnosis of These Tumors in the Liver?"

Background & Objective:

Differential diagnosis between cholangiocarcinoma (CCA) and metastatic pancreatic ductal adenocarcinoma (PDA) in the liver is difficult and so far, no specific immunohistochemical marker is reported to differentiate these two tumors. Considering the existing literature, the level of expression of Annexins (Annexin A1, 10 and 13) have been studied for differential diagnosis between these two tumors by molecular methods and promising results have been reported. Therefore, in this study, we tried to investigate the immunohistochemical value of these three Annexins for the differential diagnosis of CCA and PDA in the liver.

Methods:

The articles that reported the research subject in 10 years (2009-2019), including 45 cases of CCA and 50 cases of metastatic PDA in the liver were evaluated considering the presence or absence of AnnexinA1 (ANXA1), Annexin A10 (ANXA10) and Annexin A13 (ANXA13) expression by immunohistochemistry, were investigated.

Results & Conclusion:

This study showed, ANXA1 was positive both in PDA and CCA, ANXA10 was positive in ~60% of PDA cases and ~40% of CCA cases, and ANXA13 was mostly negative in both groups. The best sensitivity was found in cytoplasmic and nuclear ANXA1 (80% and 84%, respectively) to distinguish PDA from CCA and vice versa. The best specificity was observed in ANXA10 and ANXA13 to distinguish PDA from CCA. Also, ANXA13 had the best specificity to distinguish CCA from PDA. Our investigations showed that, ANXA1 probably can classify positive cases correctly, but it cannot discriminate PDA from CCA. ANXA10 had fair sensitivity and specificity to discriminate PDA from CCA. ANXA13 apparently had a high specificity that can help to narrow-down the differential diagnoses.

Histological Heterogeneity of Primary Liver Cancers: Clinical Relevance, Diagnostic Pitfalls and the Pathologist's Role

Simple Summary

Primary liver cancers (PLCs) mainly comprise hepatocellular carcinoma (HCC), intrahepatic cholangiocarcinoma (iCCA), and combined (c)HCC-CCA. Both small duct types iCCA (a subtype pf iCCA) and cHCC-CCA are known to be tumors with histological heterogeneity. Understanding key tumor heterogeneity is crucial as it reflects tumor aggressiveness, patient outcome, treatment choice, and is predictive of treatment efficacy. In addition, PLCs often present with multiple liver tumors, which can be a combination of different types of PLCs or HCCs (intrahepatic metastasis or multicentric occurrence), and the pathological interpretation plays an important role in these cases. The aim of this review is to clarify the pathological features of HCC, iCCA, and cHCC-CCA, including their diagnostic pitfalls, molecular profiles, and the correlation between tumor subtypes and treatment choice.

Abstract

Primary liver cancers (PLCs) mainly comprise hepatocellular carcinoma (HCC), intrahepatic cholangiocarcinoma (iCCA), and cHCC-CCA. Combined HCC-CCA and small duct type iCCA show similar clinical presentations, and their histological features are more complex than seen in HCC. Therefore, while their treatment strategy differs, it is difficult to properly diagnose these tumors. Currently, HCC is the only tumor that can be treated by liver transplantation. In addition, small duct type iCCA harbors IDH1/2 mutations and FGFR2 fusions, which can be used for targeted therapy. Thus, improving diagnostic accuracy is crucial. A further point to note is that PLCs often present as multiple liver tumors, and they can be a combination of different types of PLCs or HCCs. In the case of HCCs, two different scenarios are possible, namely intrahepatic metastasis, or multicentric occurrence. Therefore, it is essential to characterize the type of multiple liver tumors. This review aims to clarify the pathological features of HCC, iCCA and cHCC-CCA, including their diagnostic pitfalls and clinical relevance. It is designed to be of use to clinicians who are dealing with PLCs, to provide a better understanding of the pathology of these tumors, and to enable a more accurate diagnosis and optimal treatment choice.

Recognition and pathological features of periampullary region adenocarcinoma with an indeterminable origin

Determination of the primary tumor in periampullary region carcinomas can be difficult, and the pathological assessment and clinicopathological characteristics remain elusive. In this study, we investigated the current recognition and practices for periampullary region adenocarcinoma with an indeterminable origin among expert pathologists through a cognitive survey. Simultaneously, we analyzed a prospective collection of cases with an indeterminable primary tumor diagnosed from 2008 to 2018 to elucidate their clinicopathological features. All cases with pathological indeterminable primary tumors were reported and discussed in a clinicopathological conference to elucidate if it was possible to distinguish the primary tumor clinically and pathologically. From the cognitive survey, over 85% of the pathologists had experienced cases with indeterminable primary tumors; however, 70% of the cases was reported as pancreatic cancer without definitive grounds. Interpretation of the main tumor mass varied, and no standardized method was developed to determine the primary tumor. During a prospective study, 42 of the 392 periampullary carcinoma cases (10.7%) were considered as tumors with a pathological indeterminable origin. After the clinicopathological conferences, 21 (5.4%) remained indeterminable and were considered final indeterminable cases. Histological studies showed that the tumors spread along both the bile duct and main pancreatic duct; this was the most representative finding of the final indeterminable cases. This study is the first to elucidate and recognize the current clinicopathological features of periampullary region adenocarcinomas with an indeterminable origin. Adequate assessment of primary tumors in periampullary region carcinomas will help to optimize epidemiological data of pancreatic and bile duct cancer.

Tissue microarray-chip featuring computerized immunophenotypical characterization more accurately subtypes ampullary adenocarcinoma than routine histology

BACKGROUND

Ampullary adenocarcinomas (AACs) are heterogeneous tumors currently classified into three important sub-classes (SC): Intestinal (INT), Pancreato-Biliary (PB) and Mixed-Type (MT). The different subgroups have similar clinical presentation and are treated by pancreatoduodenectomy with curative intent. However, they respond differently to chemotherapy and have different prognostic outcomes. The SC are often difficult to identify with conventional histology alone. The clinical outcome of all three remains unclear, particularly for MT.

AIM

To identify two main subtypes of AACs, using an immunohistochemical (IHC) score based on CDX2, CK7 and CK20.

METHODS

Tissue samples from 21 patients who had undergone resection of AAC were classified by HE histology and IHC expression of CDX2, CK7 and CK 20. An IHC score was obtained for each marker by counting the number of positive cells (0 = no stained cells; 1 < 25%; 2 < 50% and 3 > 50%) and their intensity (1 = weak; 2 = moderate and 3 = strong). A global score (GS) was then obtained by summation of the IHC scores of each marker. The MT tumors were grouped either with the INT or PB group based on the predominant immuno-molecular phenotype, obtaining only two AACs subtypes. The overall survival in INT and PB patients was obtained by Kaplan-Meier methods.

RESULTS

Histological parameters defined the AACs subtypes as follows: 15% INT, 45% PB and 40% MT. Using IHC expression and the GS, 75% and 25% of MT samples were assigned to either the INT or the PB group. The mean value of the GS was 9.5 (range 4-16). All INT samples had a GS above the average, distinct from the PB samples which had a GS score significantly below the average (P = 0.0011). The INT samples were identified by high expression of CDX2 and CK20, whereas PB samples exhibited high expression of CK7 and no expression of CK20 (P = 0.0008). The INT group had a statistically significant higher overall survival than in the PB group (85.7 mo vs 20.3 mo, HR: 8.39; 95%CI: 1.38 to 18.90; P = 0.0152).

CONCLUSION

The combination of histopathological and molecular criteria enables the classification of AACs into two clinically relevant histo-molecular phenotypes, which appear to represent distinct disorders with potentially significant changes to the current therapeutic strategies.

Mass spectrometry-based analysis of formalin-fixed, paraffin-embedded distal cholangiocarcinoma identifies stromal thrombospondin-2 as a potential prognostic marker

Background

Distal cholangiocarcinoma is an aggressive malignancy with a dismal prognosis. Diagnostic and prognostic biomarkers for distal cholangiocarcinoma are lacking. The aim of the present study was to identify differentially expressed proteins between distal cholangiocarcinoma and normal bile duct samples.

Methods

A workflow utilizing discovery mass spectrometry and verification by parallel reaction monitoring was used to analyze surgically resected formalin-fixed, paraffin-embedded samples from distal cholangiocarcinoma patients and normal bile duct samples. Bioinformatic analysis was used for functional annotation and pathway analysis. Immunohistochemistry was performed to validate the expression of thrombospondin-2 and investigate its association with survival.

Results

In the discovery study, a total of 3057 proteins were identified. Eighty-seven proteins were found to be differentially expressed (q < 0.05 and fold change ≥ 2 or ≤ 0.5); 31 proteins were upregulated and 56 were downregulated in the distal cholangiocarcinoma samples compared to controls. Bioinformatic analysis revealed an abundance of differentially expressed proteins associated with the tumor reactive stroma. Parallel reaction monitoring verified 28 proteins as upregulated and 18 as downregulated in distal cholangiocarcinoma samples compared to controls. Immunohistochemical validation revealed thrombospondin-2 to be upregulated in distal cholangiocarcinoma epithelial and stromal compartments. In paired lymph node metastases samples, thrombospondin-2 expression was significantly lower; however, stromal thrombospondin-2 expression was still frequent (72%). Stromal thrombospondin-2 was an independent predictor of poor disease-free survival (HR 3.95, 95% CI 1.09–14.3; P = 0.037).

Conclusion

Several proteins without prior association with distal cholangiocarcinoma biology were identified and verified as differentially expressed between distal cholangiocarcinoma and normal bile duct samples. These proteins can be further evaluated to elucidate their biomarker potential and role in distal cholangiocarcinoma carcinogenesis. Stromal thrombospondin-2 is a potential prognostic marker in distal cholangiocarcinoma.

Functional and genomic characterization of three novel cell lines derived from a metastatic gallbladder cancer tumor

Background

Gallbladder cancer (GBC) is the most common tumor of the biliary tract. The incidence of GBC shows a large geographic variability, being particularly frequent in Native American populations. In Chile, GBC represents the second cause of cancer-related death among women. We describe here the establishment of three novel cell lines derived from the ascitic fluid of a Chilean GBC patient, who presented 46% European, 36% Mapuche, 12% Aymara and 6% African ancestry.

Results

After immunocytochemical staining of the primary cell culture, we isolated and comprehensively characterized three independent clones (PUC-GBC1, PUC-GBC2 and PUC-GBC3) by short tandem repeat DNA profiling and RNA sequencing as well as karyotype, doubling time, chemosensitivity, in vitro migration capability and in vivo tumorigenicity assay. Primary culture cells showed high expression of CK7, CK19, CA 19-9, MUC1 and MUC16, and negative expression of mesothelial markers. The three isolated clones displayed an epithelial phenotype and an abnormal structure and number of chromosomes. RNA sequencing confirmed the increased expression of cytokeratin and mucin genes, and also of TP53 and ERBB2 with some differences among the three cells lines, and revealed a novel exonic mutation in NF1. The PUC-GBC3 clone was the most aggressive according to histopathological features and the tumorigenic capacity in NSG mice.

Conclusions

The first cell lines established from a Chilean GBC patient represent a new model for studying GBC in patients of Native American descent.

Is Ultrasound-Guided Core Biopsy as Safe as Fine-Needle Aspiration, and Does It Add Significantly to the Diagnosis of Suspected Peritoneal Malignancy?

OBJECTIVES

We undertook this retrospective review to compare the safety and diagnostic yield of core biopsy (CB) compared to fine-needle aspiration (FNA) in patients with suspected peritoneal malignancy.

METHODS

This retrospective study included 35 patients who underwent ultrasound (US)-guided percutaneous biopsy of a peritoneal mass. Success rates of US-guided biopsy of these masses using the CB technique, FNA, or the combination of the two were compared. Outcomes of tissue adequacy, the final pathologic diagnosis, and complications were recorded. The binary outcome variable was adequate tissue obtained.

RESULTS

Adequate specimens were obtained in 94% (33 of 35) of the cases. There were 19 CBs, with 100% of samples sufficient for diagnosis (19 of 19). Thirty-one FNAs were performed, of which 7 were insufficient, with a diagnostic yield of 77% (24 of 31). There was a statistically significant difference between FNA and CB in providing more adequate tissue for diagnosis in our population (P = .035). There were no significant complications in either group.

CONCLUSIONS

The use of the CB technique when performing US-guided percutaneous biopsy of peritoneal masses provides better tissue for diagnosis compared to FNA. Additional benefits of CB, including genomic testing and tumor subtyping, make this technique a good addition to FNA, without significant complications.

Immunohistochemical profiling of liver metastases and matched-pair analysis in patients with metastatic pancreatic ductal adenocarcinoma

BACKGROUND

The purpose of the current study was to investigate the immunohistochemical (IHC) profile of liver metastases (LM) in patients with pancreatic ductal adenocarcinoma (PDAC).

METHODS

Expression of 15 IHC markers in liver biopsies from 77 patients with PDAC, who were diagnosed between 2010 and 2014, were evaluated. In a separate subgroup analysis (n = 12), paired samples (LM and primary tumor) from the same patient were investigated for IHC profile differences.

RESULTS

LM samples were classified as pancreatobiliary-type (PB-type) in 72 patients (93.5%), intestinal-type (INT-type) in four patients (5.2%), and squamous in one patient (1.3%). There was no significant difference in overall survival (OS) between LM of the PB-type or INT-type (p = 0.097). In a multivariate analysis, age <70 years (p = 0.047), absence of SMAD4 mutation (p = 0.026), absence of CDX2 expression (p = 0.003), and well to moderate differentiation were significant prognostic factors for better OS in patients with LM (p = 0.031). Analysis of paired tissue samples from LM and the primary tumor revealed a difference in CDX2 (50% increase, p = 0.125) and SMAD4 (33% loss of SMAD4, p = 0.375).

CONCLUSIONS

CDX2 expression and SMAD4 mutation indicate a poor outcome in patients with LM of PDAC. Matched-pair analysis revealed differences in distinct IHC marker expression.

Novel biomarkers distinguishing pancreatic head Cancer from distal cholangiocarcinoma based on proteomic analysis

BACKGROUND

The differentiation between pancreatic head cancer (PHC) and distal cholangiocarcinoma (DCC) can be challenging because of their anatomical and histopathological similarity. This is an important problem, because the distinction has important implications for the treatment of these malignancies. However, there are no biomarkers for the differential diagnosis of PHC and DCC. The present study aimed to identify novel diagnostic immunohistochemical biomarkers to distinguish PHC from DCC.

METHODS

Liquid chromatography tandem mass spectrometry (LC-MS/MS) was employed to detect candidate proteins. Ten PHC and 8 DCC specimens were analyzed by LC-MS/MS. Selected proteins were evaluated, using immunohistochemical analysis, to determine whether they would be appropriate biomarkers. Finally, we generated biomarker panels to improve diagnostic accuracy. We applied these panels to clinically difficult cases (cases in which different diagnoses were made before and after operation).

RESULTS

Consequently, 1820 proteins were detected using LC-MS/MS. Fifteen differentially expressed proteins were selected as candidates based on semi-quantitative comparison. We first performed immunohistochemical staining on samples from the small cohort group (12 PHCs and 12 DCCs) using 15 candidates. KRT17, ANXA10, TMEM109, PTMS, and ATP1B1 showed favorable performances and were tested in the next large cohort group (72 PHCs and 74 DCCs). Based on immunohistochemical analysis, KRT17 performed best for the diagnosis of PHC as a single marker; additionally, PTMS exhibited good performance for the diagnosis of DCCs. Moreover, we indicated the KRT17+/ANXA10+/PTMS- staining pattern as a biomarker panel for the correct diagnosis of PHC and KRT17-/ANXA10-/PTMS+ for the diagnosis of DCC. After immunohistochemical staining for examining samples from the clinically difficult cases, these panels showed satisfactory diagnostic performance with 85.7% (6/7) accuracy.

CONCLUSIONS

We conclude that 5 proteins and 2 biomarker panels are promising for distinguishing PHC from DCC, and patients with an equivocal diagnosis would benefit from the application of these biomarkers. Confirmatory studies are needed to generalize these findings to other populations.

Mucins: the Old, the New and the Promising Factors in Hepatobiliary Carcinogenesis

Mucins are large O-glycoproteins with high carbohydrate content and marked diversity in both the apoprotein and the oligosaccharide moieties. All three mucin types, trans-membrane (e.g., MUC1, MUC4, MUC16), secreted (gel-forming) (e.g., MUC2, MUC5AC, MUC6) and soluble (non-gel-forming) (e.g., MUC7, MUC8, MUC9, MUC20), are critical in maintaining cellular functions, particularly those of epithelial surfaces. Their aberrant expression and/or altered subcellular localization is a factor of tumour growth and apoptosis induced by oxidative stress and several anti-cancer agents. Abnormal expression of mucins was observed in human carcinomas that arise in various gastrointestinal organs. It was widely believed that hepatocellular carcinoma (HCC) does not produce mucins, whereas cholangiocarcinoma (CC) or combined HCC-CC may produce these glycoproteins. However, a growing number of reports shows that mucins can be produced by HCC cells that do not exhibit or are yet to undergo, morphological differentiation to biliary phenotypes. Evaluation of mucin expression levels in precursors and early lesions of CC, as well as other types of primary liver cancer (PLC), conducted in in vitro and in vivo models, allowed to discover the mechanisms of their action, as well as their participation in the most important signalling pathways of liver cystogenesis and carcinogenesis. Analysis of mucin expression in PLC has both basic research and clinical value. Mucins may act as oncogenes and tumour-promoting (e.g., MUC1, MUC13), and/or tumour-suppressing factors (e.g., MUC15). Given their role in promoting PLC progression, both classic (MUC1, MUC2, MUC4, MUC5AC, MUC6) and currently tested mucins (e.g., MUC13, MUC15, MUC16) have been proposed to be important diagnostic and prognostic markers. The purpose of this review was to summarize and update the role of classic and currently tested mucins in pathogenesis of PLC, with explaining the mechanisms of their action in HCC carcinogenesis. It also focuses on determination of the diagnostic and prognostic role of these glycoproteins in PLC, especially focusing on HCC, CC and other hepatic tumours with- and without biliary differentiation.

Clinical relevance of pancreatobiliary and intestinal subtypes of ampullary and duodenal adenocarcinoma: Pattern of recurrence, chemotherapy, and survival after pancreatoduodenectomy

BACKGROUND

The clinical relevance of the classification of ampullary adenocarcinoma (AC) into pancreatobiliary (PB) or intestinal (Int) subtypes has not been resolved.

METHODS

Clinicopathological factors, survival, and localization and treatment of recurrence were investigated for patients with AC and duodenal adenocarcinoma (DC) treated by pancreatoduodenectomy from 2000 to 2015.

RESULTS

A total of 109 AC (45 PB, 64 Int) and 71 DC (all Int) were identified. Median overall survival (OS) for ACPB vs DC vs ACInt was 43.6 vs 51 vs 75 months, respectively. ACPB had significantly shorter OS than ACInt (p = 0.036). However, for AC stage (HR = 2.39; 95 %CI 1.23-4.64, p = 0.010) was the only factor associated with mortality risk in multivariate analysis. Localization of recurrence (n = 88) was predominantly distant (ACPB 81.5%; ACInt 92%; DC 91.7%, p = 0.371). Post-recurrence survival (PRS) for ACPB, ACInt and DC did not differ (6.9 vs 9.2 vs 7.5 months, p = 0.755). Best supportive care or palliative chemotherapy were offered for recurrent disease to 44.5%/48.1% for ACPB, 40%/56% for ACInt, and 41.7%/52.8% for DC (p = 0.947). The choice of chemotherapy regimen varied considerably. Five patients underwent surgical resection or ablation with curative intent. All deaths among ACPB were caused by recurrent disease, whereas 29.4% of ACInt and 23.1% of DC deaths was non-cancer related or caused by other specific cancer.

CONCLUSION

ACPB, ACInt and DC have similar recurrence patterns and PRS. The difference in survival between ACPB and ACInt was not statistically significant when stratified by stage. The optimal chemotherapy in patients with recurrent AC remains undefined.

Cholangiocarcinoma: Classification, Histopathology and Molecular Carcinogenesis

Cholangiocarcinoma (CC) is the second most common tumor of the liver, originating from the biliary system with increasing incidence and mortality worldwide. Several new classifications review the significance of tumor localization, site of origin, proliferation and biomarkers in the intrahepatic, perihilar and distal forms of the lesion. Based on growth pattern mass-forming, periductal-infiltrating, intraductal, undefined and mixed types are differentiated. There are further subclassifications which are applied for the histological features, in particular for intrahepatic CC. Recognition of the precursors and early lesions of CC including biliary intraepithelial neoplasia (BilIN), intraductal papillary neoplasm of the bile ducts (IPNB), biliary mucinous cystic neoplasm (MCNB) and the candidate precursors, such as bile duct adenoma and von Meyenburg complex is of increasing significance. In addition to the previously used biliary markers detected by immunohistochemistry, several new markers have been added to the differentiation of both the benign and malignant lesions, which can be used to aid in the subclassification in association with the outcome of CC. Major aspects of biliary carcinogenesis have been revealed, yet, the exact way of this diverse process is still unclear. The factors contributing to molecular cholangiocarcinogenesis include various risk factors, different anatomical localizations, multiple cellular origins, genetic and epigenetic alterations, tumor microenvironment, heterogeneity and clonal evolution. Driver mutations have been identified, implying that they are optimal candidates for targeted therapy. The most promising therapeutic candidates have entered clinical trials.

Collagen IV and laminin-1 expression in embryonic mouse lens using principal components analysis technique

Immunohistochemistry section staining is not always easy to interpret. Manual quantification of immunohistochemical staining is limited by the observer visual ability to detect changes in level staining. Hence, the quantification of immunostaining by means of digital image analysis allows us to measure accurately protein expression percentages in immunobiological stained tissues and ensures to overcome the visual limitations. We perform an experimental study to analyse the impact of folic acid (FA) deficiency into collagen IV and laminin-1 expression in the embryonic mouse lens. The study starts with microscope images of embryos mouse lens whose mothers fed a diet deficient in FA during 2 and 8 weeks. A principal component analysis (PCA) image processing is used to analyse these images coming from control and FA deficit groups. The method permits to define an index of over- or infraexpression of collagen IV and laminin-1 associated to different spatial organisation structures (PC processes). Additionally, it permits to determine in precise percentage the exact quantity of the overexpression or infraexpression and finally to comprehend molecular regionalisation and expression in both control and deficient groups. The results suggest that even with 2 weeks of deficit of FA the expression and distribution of both molecules is affected.

Inflammation factors in hepatoblastoma and their clinical significance as diagnostic and prognostic biomarkers

PURPOSE

The aims of this study were to identify inflammation factors in hepatoblastoma tissue that correlated with different clinical characteristics, and to explore the probability as predictive biomarkers for diagnosis and prognosis.

METHODS

SELDI-TOF-MS was performed to screen protein peaks that were significantly highly expressed in tumor tissue compared with adjacent liver tissue. After removing proteins larger than 30kDa, the targeted peaks were separated by solid phase extraction and tricine-SDS-PAGE. Protein fragments produced by in-gel digestion were identified by LC-MS/MS. Immunohistochemical assays further confirmed these results. Overall survival curves were graphed by Kaplan-Meier method and multivariate analysis was performed by Cox proportional hazards regression model.

RESULTS

Three protein peaks (m/z 12,138, m/z 13,462, and m/z 15,120) that were significantly upregulated in the tumor tissue were identified as macrophage migration inhibitory factor (MIF), chemokine (C-X-C motif) ligand 7 (CXCL7), and interleukin 25 (IL-25). These factors were closely related to clinical stage, lymph node metastasis, vascular invasion and serum AFP level. High expression of each inflammatory marker indicated poor prognosis. Multivariate analysis suggested that MIF, CXCL7, and IL-25 were prognostic factors independent of patient sex, age and tumor histological type.

CONCLUSIONS

MIF, CXCL7, and IL-25 might be considered as effective inflammation factors for diagnosis and prognosis of hepatoblastoma and as potential novel treatment targets through inhibition of inflammatory function.

TYPE OF STUDY

Prognosis study LEVEL OF EVIDENCE: Level I.