Biliary dysplasia in primary sclerosing cholangitis harbors cytogenetic abnormalities similar to cholangiocarcinoma

Next-generation sequencing mutation analysis on biliary brush cytology for differentiation of benign and malignant strictures in primary sclerosing cholangitis

BACKGROUND AND AIMS

Differentiation of benign and malignant biliary tract strictures on brush material remains highly challenging but is essential for adequate clinical management of patients with primary sclerosing cholangitis (PSC). In this case-control study, biliary brush cytology samples from PSC patients with cholangiocarcinoma (PSC-CCA) were compared with samples from PSC patients without CCA (PSC-control subjects) using next-generation sequencing (NGS).

METHODS

Cells on archived slides were dissected for DNA extraction. NGS was performed using a gene panel containing 242 hotspots in 14 genes. Repeated brush samples from the same patient were analyzed to study the consistency of NGS results. In PSC-CCA cases that underwent surgical resection, molecular aberrations in brush samples were compared with NGS data from subsequent resection specimens.

RESULTS

Forty patients (20 PSC-CCA and 20 PSC-control subjects) were included. The gene panel detected 22 mutations in 15 of 20 PSC-CCA brush samples, including mutations in TP53 (8 brush samples), K-ras (5), G-nas (3), ERBB2 (1), APC (1), PIK3CA (1), and SMAD4 (1). One G-nas and 3 K-ras mutations were found in 3 of 20 PSC-control brush samples. The sensitivity of the NGS panel was 75% (95% confidence interval, 62%-80%) and specificity 85% (95% confidence interval, 64%-95%). Repeated brush samples showed identical mutations in 6 of 9 cases. Three repeated brush samples demonstrated additional mutations as compared with the first brush sample. In 6 of 7 patients, mutations in brush samples were identical to mutations in subsequent resection specimens.

CONCLUSIONS

NGS mutation analysis of PSC brush cytology detects oncogenic mutations with high sensitivity and specificity and seems to constitute a valuable adjunct to cytologic assessment of brush samples.

Diagnostic pitfalls and the value of fluorescence in situ hybridization as an adjunct to cytologic evaluation of bile duct brushings in patients with primary sclerosing cholangitis

BACKGROUND

Primary sclerosing cholangitis (PSC) can present diagnostic difficulties on bile duct brushings as cytologic features mimicking adenocarcinoma may exist. This study evaluates the role of fluorescence in-situ hybridization (FISH) as an adjunct to cytologic evaluation.

METHODS

From January 1, 2020, through December 31, 2021, 308 bile duct brushings were processed of which 34 (11%) were malignant, 25 (8%) were suspicious, 36 (12%) were atypical, 204 (66%) were negative and 10 (3%) were nondiagnostic. Follow-up biopsies/resections were performed in the 95 cases with diagnostic cytology (atypical/suspicious/malignant) of which 12 (13%) showed primary sclerosing cholangitis and form the basis of this study. Cytologic, histologic and FISH findings are presented and discussed.

RESULTS

Of the 12 bile duct brushings 4 (34%) were positive/suspicious for adenocarcinoma and 8 (66%) showed atypical epithelial cells. FISH was positive in 2/4 positive/suspicious brushings and negative in the remaining 2 brushings. Histologic findings confirmed the FISH results. The cytologic features of the 2 false positive cases overlapped those of adenocarcinoma. Two of the 8 bile duct brushings with atypical epithelial cells were positive/suspicious for adenocarcinoma on FISH analysis; findings confirmed on histologic follow-up. The remaining 8 patients underwent surveillance for the development of adenocarcinoma with repeat bile duct brushings, FISH analysis and biopsies, each of which has been negative to date.

CONCLUSION

FISH, as an adjunct to the cytologic evaluation of bile duct brushings from patients with PSC, plays a role in improving diagnostic accuracy and serves as a surveillance tool for the potential development of adenocarcinoma.

Genetic alterations during the neoplastic cascade towards cholangiocarcinoma in primary sclerosing cholangitis

Carcinogenesis of primary sclerosing cholangitis (PSC)-associated cholangiocarcinoma (CCA) is largely unexplored. Improved understanding of the molecular events involved may guide development of novel avenues for rational clinical management. We aimed to assess the genetic alterations during progression of the neoplastic cascade from biliary dysplasia towards CCA in PSC. Forty-four resection specimens or biopsies of PSC patients with biliary dysplasia (n = 2) and/or CCA (n = 42) were included. DNA was extracted from sections of formalin-fixed paraffin-embedded tissue blocks with dysplasia (n = 23), CCA (n = 69), and nonneoplastic tissue (n = 28). A custom-made next-generation sequencing (NGS) panel of 28 genes was used for mutation and copy number variation (CNV) detection. In addition, CNVs of CDKN2A, EGFR, MCL1, and MYC were examined by fluorescence in situ hybridization. Alterations in 16 low-grade dysplasia samples included loss of FGFR1 (19%), CDKN2A (13%), and SMAD4 (6%), amplification of FGFR3 (6%), EGFR (6%), and ERBB2 (6%), and mutations in SMAD4 (13%). High-grade dysplasia (n = 7) is characterized by MYC amplification (43%), and mutations in ERBB2 (71%) and TP53 (86%). TP53 mutations are the most common aberrations in PSC-CCA (30%), whereas mutations in KRAS (16%), GNAS (14%), and PIK3CA (9%) are also common. In conclusion, PSC-CCA exhibits a variety of genetic alterations during progression of the neoplastic cascade, with mainly CNVs being present early, whereas mutations in ERBB2, TP53, and KRAS appear later in the development of CCA. These findings are promising for the development of NGS-guided diagnostic strategies in PSC-CCA. © 2022 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

The Cytomorphologic and Molecular Assessment of Bile Duct Brushing Specimens

Biliary duct brushing cytology is the standard of care for the assessment of bile duct strictures but suffers from low sensitivity for the detection of a high-risk stricture. Pathologic diagnosis of strictures is optimized by integration of cytomorphology and molecular analysis with fluorescence in situ hybridization or next-generation sequencing. Bile duct cancers are genetically heterogeneous, requiring analysis of multiple gene panels to increase sensitivity. Using molecular analysis as an ancillary test for bile duct brushing samples aids in the identification of mutations that support the diagnosis of a high-risk stricture as well as the identification of actionable mutations for targeted therapies currently in clinical trials for the treatment of patients with bile duct cancer.

The Role of Microbiota in Primary Sclerosing Cholangitis and Related Biliary Malignancies

Primary sclerosing cholangitis (PSC) is an immune-related cholangiopathy characterized by biliary inflammation, cholestasis, and multifocal bile duct strictures. It is associated with high rates of progression to end-stage liver disease as well as a significant risk of cholangiocarcinoma (CCA), gallbladder cancer, and colorectal carcinoma. Currently, no effective medical treatment with an impact on the overall survival is available, and liver transplantation is the only curative treatment option. Emerging evidence indicates that gut microbiota is associated with disease pathogenesis. Several studies analyzing fecal and mucosal samples demonstrate a distinct gut microbiome in individuals with PSC compared to healthy controls and individuals with inflammatory bowel disease (IBD) without PSC. Experimental mouse and observational human data suggest that a diverse set of microbial functions may be relevant, including microbial metabolites and bacterial processing of pharmacological agents, bile acids, or dietary compounds, altogether driving the intrahepatic inflammation. Despite critical progress in this field over the past years, further functional characterization of the role of the microbiota in PSC and related malignancies is needed. In this review, we discuss the available data on the role of the gut microbiome and elucidate important insights into underlying pathogenic mechanisms and possible microbe-altering interventions.

[Surgical treatment of primary sclerosing cholangitis : Experiences from 30 years in a single center cohort with 173 consecutive patients]

BACKGROUND

In recent years substantial progress has been made in the treatment, surveillance and understanding of the pathogenesis of primary sclerosing cholangitis (PSC); however, in most cases liver transplantation (LTX) is still the only curative option for cancer or end-stage liver disease (ELD). In rare cases a partial liver resection is a possible curative treatment of a PSC-associated cholangiocellular carcinoma (CCC). These operations represent a significant additional burden for PSC patients.

OBJECTIVE

Due to the rarity of PSC detailed studies regarding hepato-pancreato-biliary (HPB) surgery are lacking. The aim of this study was to analyze the surgical indications and prognosis of PSC patients.

PATIENTS AND METHODS

A single center retrospective cohort study from 1990 to 2020 was carried out. In this study patients with PSC were included and investigated with respect to factors associated with surgery and the prognosis.

RESULTS

As a consequence of PSC-associated conditions, in 62 patients (36%) a major HPB operation or explorative laparotomy was necessary. The prevalence of chronic inflammatory bowel disease was significantly higher in these patients (P < 0.019). An LTX was carried out in 46 patients (73%) because of ELD. A liver resection (LR) was performed in 8 patients (11%) and 9 patients only underwent an explorative laparotomy. The overall survival in the LTX subgroup was significantly longer than patients who underwent LR and explorative laparotomy (258 months; 95% confidence interval, CI 210-306 months vs. 88 months; 95% CI 16-161 months vs. 13 months; 95% CI 3-23 months; p < 0.05, respectively).

CONCLUSION

The majority of patients with PSC have to be operated on because of the disease with substantial risks for morbidity and mortality. Curative treatment options are lacking, thus underlining the need for effective early detection and treatment strategies for PSC-CCC.

Carriers of ABCB4 gene variants show a mild clinical course, but impaired quality of life and limited risk for cholangiocarcinoma

BACKGROUND AND AIMS

Adenosine triphosphate-binding cassette subfamily B member 4 (ABCB4) deficiency may lead to progressive familial intrahepatic cholestasis type 3 (PFIC3), biliary cirrhosis, low phospholipid-associated cholelithiasis (LPAC), intrahepatic cholestasis of pregnancy (ICP), oral contraceptive-induced cholestasis (CIC) or may remain asymptomatic. The long-term course, quality of life and histology were investigated in ABCB4 deficiency.

METHODS

Adult carriers of ABCB4 gene variants from two regional academic centres were analysed by history taking, electronic patient files, physical examination, blood analysis, abdominal ultrasound (US) and liver elastography. Patients completed a 36-Item Short Form Health Survey (SF-36) for quality of life and a Visual Analogue Scale (VAS) for pruritus. Available liver specimens were re-classified according to the Nakanuma scoring system, so far validated for primary biliary cholangitis (PBC) and primary sclerosing cholangitis (PSC) only. Quality of life data were compared to published data of patients with PBC, PSC and the general population.

RESULTS

Sixty-seven patients were identified, 64 (96%) were alive at the time of analysis and 62 (93%) were (at some time) treated with ursodeoxycholic acid (UDCA). Two patients died of cholangiocarcinoma (CCA), and one of decompensated biliary cirrhosis. Three additional deaths of CCA were reported in first-degree relatives. Transplant-free survival was 91% (median follow-up 14 years). Liver stiffness was normal (<6.3 kPa) in 75%, intrahepatic stones were detected at ultrasound (US) in 33% and microcalcifications in 22% of cases. Quality of life (n = 48) was lower than in the general population particularly in energy/fatigue and general health domains and comparable to that in PSC. Staging according to Nakanuma in 15 specimens reflected the clinical course.

CONCLUSIONS

ABCB4 deficiency has a mild clinical course, but impaired quality of life and limited risk of CCA. The Nakanuma scoring system appears feasible for histological evaluation in ABCB4 deficiency.

Cholangiocarcinoma in Patients with Primary Sclerosing Cholangitis (PSC): a Comprehensive Review

Cholangiocarcinoma (CCA) is the most common malignancy in patients with primary sclerosing cholangitis (PSC) and carries a high rate of mortality. Although the pathogenesis of CCA in PSC is largely unknown, inflammation-driven carcinogenesis concomitant with various genetic and epigenetic abnormalities are underlying factors. The majority of CCA cases develop from a dominant stricture (DS), which is defined as a stricture with a diameter < 1.5 mm in the common bile duct or < 1.0 mm in the hepatic duct. In PSC patients presenting with an abrupt aggravation of jaundice, pain, fatigue, pruritus, weight loss, or worsening liver biochemistries, CCA should be suspected and evaluated utilizing a variety of diagnostic modalities. However, early recognition of CCA in PSC remains a major challenge. Importantly, 30-50% of CCA in PSC patients are observed within the first year following the diagnosis of PSC followed by an annual incidence ranging from 0.5 to 1.5 per 100 persons, which is nearly 10 to 1000 times higher than that in the general population. Cumulative 5-year, 10-year, and lifetime incidences are 7%, 8-11%, and 9-20%, respectively. When PSC-associated CCA is diagnosed, most tumors are unresectable, and no effective medications are available. Given the poor therapeutic outcome, the surveillance and management of PSC patients who are at an increased risk of developing CCA are of importance. Such patients include older males with large-duct PSC and possibly concurrent ulcerative colitis. Thus, more attention should be paid to patients with these clinical features, in particular within the first year after PSC diagnosis. In contrast, CCA is less frequently observed in pediatric or female PSC patients or in those with small-duct PSC or concurrent Crohn's disease. Recently, new biomarkers such as antibodies to glycoprotein 2 have been found to be associated with an increased risk of developing CCA in PSC. Herein, we review the literature on the pathogenesis, incidence, clinical features, and risk factors, with a focus on various diagnostic modalities of PSC-associated CCA.

DNA flow cytometric analysis of paraffin-embedded tissue for the diagnosis of malignancy in bile duct biopsies

Differentiation of reactive versus neoplastic epithelial changes can be challenging in bile duct biopsies. The samples are often scant, distorted, and mixed with significant inflammation, ulceration, and/or debris. Histological confirmation of malignancy is often required before the initiation of surgical therapy, and an erroneous diagnosis of malignancy can lead to unnecessary clinical management. Aneuploidy assessment by DNA flow cytometry was performed on formalin-fixed paraffin-embedded (FFPE) tissue from 63 bile duct biopsies: 10 with a malignant diagnosis (7 with adenocarcinoma and 3 with at least high-grade dysplasia [HGD]); 3 with an atypical diagnosis showing rare atypical glands/cells, concerning but not definite for malignancy; 28 likely reactive biopsies with acute/chronic inflammation, ulceration, and/or mild nuclear atypia; and 22 additional benign biopsies without significant inflammation, ulceration, or nuclear atypia. Aneuploidy was detected in 7 (70%) of the 10 biopsies with definite neoplasia (5 of 7 adenocarcinoma cases and 2 of 3 at least HGD cases), all 3 (100%) atypical biopsies, and none of the 50 benign biopsies. All 3 atypical cases with aneuploidy were subsequently found to have adenocarcinoma (n = 2) or HGD (n = 1). Among the 2 cases of at least HGD with aneuploidy, 1 case developed adenocarcinoma, but no follow-up information was available in the other case. The remaining 1 case of at least HGD, despite having normal DNA content, was found to have adenocarcinoma on follow-up. None of the 50 benign cases (further supported by normal DNA content) developed adenocarcinoma within a mean follow-up time of 37 months (range: 0-282 months). The estimated sensitivity of aneuploidy as a diagnostic marker of malignancy (adenocarcinoma and HGD) was 70%, with the specificity of 100%, positive predictive value of 100%, and negative predictive value of 94%. In conclusion, DNA flow cytometry using FFPE tissue from bile duct biopsies demonstrates a high rate of aneuploidy (70%) in malignant cases and normal DNA content in all benign biopsies. Although the sample size is small, the results indicate that this assay can be potentially useful in challenging atypical cases, where morphological evaluation is limited by scarcity of atypical glands/cells, inflammation, and/or ulceration.

Expression of endoplasmic reticulum oxidoreductase 1-α in cholangiocarcinoma tissues and its effects on the proliferation and migration of cholangiocarcinoma cells

Abstract

Endoplasmic reticulum oxidoreductase 1-α (ERO1A) is a kind of hypoxia-induced endoplasmic reticulum oxidase that regulates translation and folding of oxidized proteins. This study aimed to explore the clinicopathological significance of ERO1A and the effect on the biological behavior of cholangiocarcinoma (CCA) cells.

Methods

Immunohistochemical staining was used to detect the expression of ERO1A, carcinoembryonic antigen (CEA), and carbohydrate antigen 19–9 (CA19-9) in cholangiocarcinoma. Immunofluorescence staining was performed to detect the subcellular localization of ERO1A in CCA cells. The expression of ERO1A in CAA cells after depletion or overexpression was verified by Western blot assay. Then, the effect of ERO1A on proliferation in CCA cells was verified by MTT assay and colony formation assay. Wound healing assays and migration assays were performed to detect the effect of ERO1A on cell migration ability. Finally, we explored the role of ERO1A in EMT and Akt/mTOR signaling pathway.

Results

In this study, our data demonstrated that ERO1A, CEA, and CA19-9 were expressed in cholangiocarcinoma tissues, and the positive rates were 95%, 95%, and 55%, respectively. The high expression of ERO1A is associated with clinical stage and pathological stage of CCA. In vitro data indicate that deletion of ERO1A can inhibit the proliferation and migration of CCA cells and vice versa. In addition, ERO1A has been shown to be closely related to EMT and Akt/mTOR pathways.

Conclusion

In summary, we found that high expression of ERO1A is associated with poor prognosis in patients, and ERO1A can promote the proliferation and migration of CCA cells. In conclusion, ERO1A can be used as an independent biomarker for predicting the prognosis of CCA.

Suspicious brush cytology is an indication for liver transplantation evaluation in primary sclerosing cholangitis

AIM

To investigate markers for high-grade dysplasia for the optimal timing of liver transplantation in patients with primary sclerosing cholangitis (PSC).

METHODS

Earlier data support a dysplasia-carcinoma sequence, even low- to high-grade dysplasia, in PSC-associated cholangiocarcinoma (CCA). Surveillance using endoscopic retrograde cholangiography (ERC) and brush cytology aims to detect cases of biliary dysplasia, and liver transplantation is an option in cases with suspicion of malignancy in brushing. This study investigated markers to identify patients with high-grade biliary dysplasia for optimal timing in early liver transplantation. Patients undergoing surveillance using ERC and brush cytology during 2008-2014 and who were diagnosed with biliary dysplasia in explanted liver or CCA until February 2016 were included in the study. Demographic data, cholangiography findings, laboratory values, cytological morphology and DNA ploidy were analysed.

RESULTS

Thirty PSC patients had biliary neoplasia in the explanted liver during the study period. Sixteen of these patients had low-grade dysplasia, 10 patients had high-grade dysplasia, and 4 patients had CCA. Fifteen PSC patients diagnosed with CCA were not transplanted. Patients with low-grade dysplasia were younger. Alkaline phosphatase or carcinoembryonic antigen values did not differ between groups during surveillance, but carbohydrate antigen 19-9 was higher in CCA patients. No difference in PSC duration, ERC scores, suspicious cytology, or ploidy analysis was found between groups. No difference was observed between fibrosis stage in explanted livers. Low- and high-grade dysplasia could not be differentiated before liver transplantation based on liver enzymes, tumour markers, ERC scores, brush cytology or DNA ploidy.

CONCLUSION

Repeated suspicion of neoplasia in brush cytology should be an indication for evaluations of liver transplantation prior to the development of CCA.

Cholangiocytes in the pathogenesis of primary sclerosing cholangitis and development of cholangiocarcinoma

Primary sclerosing cholangitis (PSC) is an idiopathic cholangiopathy strongly associated with inflammatory bowel disease (IBD) and characterized by cholestasis, chronic immune infiltration and progressive fibrosis of the intrahepatic and extrahepatic bile ducts. PSC confers a high risk of cholangiocarcinoma (CCA) with PSC-CCA representing the leading cause of PSC-associated mortality. PSC-CCA is derived from cholangiocytes and associated progenitor cells - a heterogeneous group of dynamic epithelial cells lining the biliary tree that modulate the composition and volume of bile production by the liver. Infection, inflammation and cholestasis can trigger cholangiocyte activation leading to an increased expression of adhesion and antigen-presenting molecules as well as the release of various inflammatory and fibrogenic mediators. As a result, activated cholangiocytes engage in a myriad of cellular processes, including hepatocellular proliferation, apoptosis, angiogenesis and fibrosis. Cholangiocytes can also regulate the recruitment of immune cells, mesenchymal cells, and endothelial cells that participate in tissue repair and destruction in settings of persistent inflammation. In PSC, the role of cholangiocytes and the mechanisms governing their transformation to PSC-CCA are unclear however localization of disease suggests that cholangiocytes are a key target and potential regulator of hepatobiliary immunity, fibrogenesis and tumorigenesis. Herein, we summarize mechanisms of cholangiocyte activation in PSC and highlight new insights into disease pathways that may contribute to the development of PSC-CCA. This article is part of a Special Issue entitled: Cholangiocytes in Health and Disease edited by Jesus Banales, Marco Marzioni, Nicholas LaRusso and Peter Jansen.

Surveillance of primary sclerosing cholangitis with ERC and brush cytology: risk factors for cholangiocarcinoma

OBJECTIVE

Primary sclerosing cholangitis (PSC) is a chronic cholestatic liver disease leading to bile duct strictures and fibrosis, and predisposing to cholangiocarcinoma (CCA). Biliary dysplasia is a known precursor of CCA. In our unit, PSC patients undergo regular surveillance with ERC and brush cytology (BC), and liver transplantation is an option in case with biliary dysplasia. We evaluated the risk factors for biliary dysplasia and CCA based on ERC imaging, BC and liver function tests.

PATIENTS AND METHODS

Seven hundred and eighty-eight ERCs were performed with BC for 447 PSC patients. ERC images were evaluated using the modified Amsterdam score, neutrophilic inflammation was assessed in BC, and liver function tests were collected. Ploidy analysis with DNA flow cytometry was performed in cases with advanced PSC or previous suspicious BC/aneuploidy. The endpoint was either a benign disease course (follow-up for ≥2.4 years after the latest ERC), benign histology, biliary dysplasia or CCA.

RESULTS

Benign disease course was seen in 424/447 (including 23 cases with biliary dysplasia), and CCA in 17 (3.8%) patients. Gallbladder carcinoma/carcinoma in situ was diagnosed in three patients. Advanced ERC findings, male gender, suspicious BC, aneuploidy in flow cytometry, inflammation, and elevation of ALP, bilirubin, ALT, AST, GGT, CEA and CA19-9 represented significant risk factors for CCA in univariate analysis.

CONCLUSIONS

PSC patients with advanced bile duct disease and elevated liver enzymes, CEA or CA19-9, inflammation or suspicious BC are most likely to develop CCA. These patients may benefit from surveillance with BC if early liver transplantation is possible.

No Evidence That Azathioprine Increases Risk of Cholangiocarcinoma in Patients With Primary Sclerosing Cholangitis

BACKGROUND & AIMS

Patients with primary sclerosing cholangitis (PSC) are at increased risk for developing cholangiocarcinoma (CCA). Patients with PSC also can have inflammatory bowel diseases (IBDs) or features of autoimmune hepatitis (AIH), and therefore are treated with azathioprine. Azathioprine has been associated with an increased risk for malignancy, therefore we investigated whether azathioprine use affects the risk of CCA in persons with PSC.

METHODS

We performed a retrospective study of well-defined patients with PSC using data collected from 3 large-volume, tertiary care centers in Germany and Norway. We analyzed data from 638 patients (70% men; 5900 patient-years of follow-up evaluation); 91 patients had received azathioprine therapy (considered to be effective at 90 days after first intake). Risk analysis was performed using the Cox proportional hazard model when risks competing with study end points were present.

RESULTS

Of patients who received azathioprine treatment, 3.3% developed CCA, compared with 6.8% of patients without azathioprine treatment. However, azathioprine did not significantly affect the risk for CCA (hazard ratio, 0.96; 95% confidence interval, 0.29-3.13; P = .94). The only factor associated with an increased risk of CCA was age 35 years or older at PSC diagnosis (hazard ratio, 3.87; 95% confidence interval, 1.96-7.67; P < .01). Patient sex, concomitant IBD, or AIH did not affect the risk of CCA. Overall, the cumulative 10-year incidence of CCA was 4.6% and the cumulative 15-year incidence was 7.7%.

CONCLUSIONS

A retrospective analysis of patients with PSC treated at tertiary centers in Europe found no evidence that azathioprine significantly affects the risk of CCA. Azathioprine therefore should not be withheld from patients with PSC and concomitant IBD and/or AIH.

Updates on Precancerous Lesions of the Biliary Tract: Biliary Precancerous Lesion

Precursor lesions of invasive adenocarcinoma of the bile duct (cholangiocarcinoma) have been increasingly recognized during the past decade because of the results of multiple studies on the carcinogenesis of cholangiocarcinoma, technologic advancements in diagnostic imaging modalities, and an increase in the volume of elective procedures. The two main precursor lesions of cholangiocarcinoma that have evolved are biliary intraepithelial neoplasia and intraductal papillary neoplasm of the bile duct. These lesions demonstrate histomorphologic similarities to pancreatic intraepithelial neoplasia and intraductal papillary mucinous neoplasm of the pancreas, respectively, whereas mechanisms of carcinogenesis and risk of progressive disease appear distinct. An enhanced understanding of the clinical presentation and pathologic features of precursor lesions of the biliary tract and use of the correct terminology will facilitate efficient communication between surgeons, oncologists, and pathologists and improve quality of patient care.

Risk and Surveillance of Cancers in Primary Biliary Tract Disease

Primary biliary diseases have been associated in several studies with various malignancies. Understanding the risk and optimizing surveillance strategy of these malignancies in this specific subset of patients are an important facet of clinical care. For instance, primary sclerosing cholangitis is associated with an increased risk for cholangiocarcinoma (which is very challenging to diagnose) and when IBD is present for colorectal cancer. On the other hand, primary biliary cirrhosis patients with cirrhosis or not responding to 12 months of ursodeoxycholic acid therapy are at increased risk of hepatocellular carcinoma. In this review we will discuss in detail the risks and optimal surveillance strategies for patients with primary biliary diseases.

An Optimized Set of Fluorescence In Situ Hybridization Probes for Detection of Pancreatobiliary Tract Cancer in Cytology Brush Samples

BACKGROUND & AIMS

Pancreatobiliary cancer is detected by fluorescence in situ hybridization (FISH) of pancreatobiliary brush samples with UroVysion probes, originally designed to detect bladder cancer. We designed a set of new probes to detect pancreatobiliary cancer and compared its performance with that of UroVysion and routine cytology analysis.

METHODS

We tested a set of FISH probes on tumor tissues (cholangiocarcinoma or pancreatic carcinoma) and non-tumor tissues from 29 patients. We identified 4 probes that had high specificity for tumor vs non-tumor tissues; we called this set of probes pancreatobiliary FISH. We performed a retrospective analysis of brush samples from 272 patients who underwent endoscopic retrograde cholangiopancreatography for evaluation of malignancy at the Mayo Clinic; results were available from routine cytology and FISH with UroVysion probes. Archived residual specimens were retrieved and used to evaluate the pancreatobiliary FISH probes. Cutoff values for FISH with the pancreatobiliary probes were determined using 89 samples and validated in the remaining 183 samples. Clinical and pathologic evidence of malignancy in the pancreatobiliary tract within 2 years of brush sample collection was used as the standard; samples from patients without malignancies were used as negative controls. The validation cohort included 85 patients with malignancies (46.4%) and 114 patients with primary sclerosing cholangitis (62.3%). Samples containing cells above the cutoff for polysomy (copy number gain of ≥2 probes) were classified as positive in FISH with the UroVysion and pancreatobiliary probes. Multivariable logistic regression was used to estimate associations between clinical and pathology findings and results from FISH.

RESULTS

The combination of FISH probes 1q21, 7p12, 8q24, and 9p21 identified cancer cells with 93% sensitivity and 100% specificity in pancreatobiliary tissue samples and were therefore included in the pancreatobiliary probe set. In the validation cohort of brush samples, pancreatobiliary FISH identified samples from patients with malignancy with a significantly higher level of sensitivity (64.7%) than the UroVysion probes (45.9%) (P < .001) or routine cytology analysis (18.8%) (P < .001), but similar specificity (92.9%, 90.8%, and 100.0% respectively). Factors significantly associated with detection of carcinoma, in adjusted analyses, included detection of polysomy by pancreatobiliary FISH (P < .001), a mass by cross-sectional imaging (P < .001), cancer cells by routine cytology (overall P = .003), as well as absence of primary sclerosing cholangitis (P = .011).

CONCLUSIONS

We identified a set of FISH probes that detects cancer cells in pancreatobiliary brush samples from patients with and without primary sclerosing cholangitis with higher levels of sensitivity than UroVysion probes. Cytologic brushing test results and clinical features were independently associated with detection of cancer and might be used to identify patients with pancreatobiliary cancers.

Primary Sclerosing Cholangitis as a Premalignant Biliary Tract Disease: Surveillance and Management

Primary sclerosing cholangitis (PSC) is a premalignant biliary tract disease that confers a significant risk for the development of cholangiocarcinoma (CCA). The chronic biliary tract inflammation of PSC promotes pro-oncogenic processes such as cellular proliferation, induction of DNA damage, alterations of the extracellular matrix, and cholestasis. The diagnosis of malignancy in PSC can be challenging because inflammation-related changes in PSC may produce dominant biliary tract strictures mimicking CCA. Biomarkers such as detection of methylated genes in biliary specimens represent noninvasive techniques that may discriminate malignant biliary ductal changes from PSC strictures. However, conventional cytology and advanced cytologic techniques such as fluorescence in situ hybridization for polysomy remain the practice standard for diagnosing CCA in PSC. Curative treatment options of malignancy arising in PSC are limited. For a subset of patients selected by using stringent criteria, liver transplantation after neoadjuvant chemoradiation is a potential curative therapy. However, most patients have advanced malignancy at the time of diagnosis. Advances directed at identifying high-risk patients, early cancer detection, and development of chemopreventive strategies will be essential to better manage the cancer risk in this premalignant disease. A better understanding of dysplasia definition and especially its natural history is also needed in this disease. Herein, we review recent developments in our understanding of the risk factors, pathogenic mechanisms of PSC associated with CCA, as well as advances in early detection and therapies.

Epidemiology of cholangiocarcinoma

Cholangiocarcinoma (CCA) is a cancer arising from the intra- or extrahepatic bile ducts and mainly characterized by its late diagnosis and fatal outcome. CCA is the second most common primary liver tumour and accounts for approximately 10-15% of all hepatobiliary malignancies. The development of CCA is linked to a wide spectrum of conditions causing biliary inflammation, cholestasis and inflammation of the liver. The geographic diversity of risk factors is reflected in considerable differences in incidence worldwide. Although data are not consistent, incidence seems to be rising in the Western World. Given the limited opportunities of treating advanced CCA, surveillance has been suggested as a strategy for detection of early disease in the high-risk group of patients with primary sclerosing cholangitis (PSC). In this review we present an updated overview of the epidemiology of CCA. We also highlight the risk of CCA in PSC with special focus on surveillance strategies.

Cancer review: Cholangiocarcinoma

Cholangiocarcinoma (CCA) is the most common biliary tract malignancy. CCA is classified as intrahepatic, perihilar or distal extrahepatic; the individual subtypes differ in their biologic behavior, clinical presentation, and management. Throughout the last decades, CCA incidence rates had significantly increased. In addition to known established risk factors, novel possible risk factors (i.e. obesity, hepatitis C virus) have been identified that are of high importance in developed countries where CCA prevalence rates have been low. CCA tends to develop on the background of inflammation and cholestasis. In recent years, our understanding of the molecular mechanisms of cholangiocarcinogenesis has increased, thereby, providing the basis for molecularly targeted therapies. In its diagnostic evaluation, imaging techniques have improved, and the role of complementary techniques has been defined. There is a need for improved CCA biomarkers as currently used ones are suboptimal. Multiple staging systems have been developed, but none of these is optimal. The prognosis of CCA is considered dismal. However, treatment options have improved throughout the last two decades for carefully selected subgroups of CCA patients. Perihilar CCA can now be treated with orthotopic liver transplantation with neoadjuvant chemoradiation achieving 5-year survival rates of 68%. Classically considered chemotherapy-resistant, the ABC-02 trial has shown the therapeutic benefit of combination therapy with gemcitabine and cisplatin. The benefits of adjuvant treatments for resectable CCA, local ablative therapies and molecularly targeted therapies still need to be defined. In this article, we will provide the reader with an overview over CCA, and discuss the latest developments and controversies.