Characterization and clinical course of hepatobiliary carcinoma in patients with primary sclerosing cholangitis

Predicting cholangiocarcinoma in primary sclerosing cholangitis: using artificial intelligence, clinical and laboratory data

BACKGROUND

Primary sclerosing cholangitis (PSC) patients have a risk of developing cholangiocarcinoma (CCA). Establishing predictive models for CCA in PSC is important.

METHODS

In a large cohort of 1,459 PSC patients seen at Mayo Clinic (1993-2020), we quantified the impact of clinical/laboratory variables on CCA development using univariate and multivariate Cox models and predicted CCA using statistical and artificial intelligence (AI) approaches. We explored plasma bile acid (BA) levels' predictive power of CCA (subset of 300 patients, BA cohort).

RESULTS

Eight significant risk factors (false discovery rate: 20%) were identified with univariate analysis; prolonged inflammatory bowel disease (IBD) was the most important one. IBD duration, PSC duration, and total bilirubin remained significant (p < 0.05) with multivariate analysis. Clinical/laboratory variables predicted CCA with cross-validated C-indexes of 0.68-0.71 at different time points of disease, significantly better compared to commonly used PSC risk scores. Lower chenodeoxycholic acid, higher conjugated fraction of lithocholic acid and hyodeoxycholic acid, and higher ratio of cholic acid to chenodeoxycholic acid were predictive of CCA. BAs predicted CCA with a cross-validated C-index of 0.66 (std: 0.11, BA cohort), similar to clinical/laboratory variables (C-index = 0.64, std: 0.11, BA cohort). Combining BAs with clinical/laboratory variables leads to the best average C-index of 0.67 (std: 0.13, BA cohort).

CONCLUSIONS

In a large PSC cohort, we identified clinical and laboratory risk factors for CCA development and demonstrated the first AI based predictive models that performed significantly better than commonly used PSC risk scores. More predictive data modalities are needed for clinical adoption of these models.

Risk stratification in primary sclerosing cholangitis

Primary sclerosing cholangitis (PSC) is a chronic liver disorder commonly affecting young patients and associated with uncertain prognosis and elevated risk of end-stage liver disease and hepatobiliary cancer. Rate of progression in PSC is heterogeneous and accurately predicting the disease course is of paramount importance to clinical practice and interventional trial design. So far, efforts have brought to the development of models looking at short-to-middle-term outcome using composite models including clinical, laboratory, radiological and histological parameters with limited performance. In the era of whole genome sequencing and digital innovation, the time is ripe for the development of stratified medicine in PSC. Efforts should be directed toward developing well-phenotyped cohorts of patients with longitudinal follow-up across sustained periods of time, application of novel image-processing technology, and biomarker discovery using multiomics platforms.

Epidemiology and outcomes of primary sclerosing cholangitis: an Australian multicentre retrospective cohort study

Background and aims

Little is known regarding the epidemiology and outcomes of patients with primary sclerosing cholangitis (PSC) in Australia. We, therefore, evaluated the epidemiology and clinical outcomes of PSC in a large cohort of Australian patients and compared these to the general population.

Methods

We conducted a multicentre, retrospective cohort study of PSC patients at nine tertiary liver centers across three Australian states, including two liver transplant centers.

Results

A total of 413 PSC patients with 3,285 person-years of follow-up were included. Three hundred and seventy-one (90%) patients had large duct PSC and 294 (71%) had associated inflammatory bowel disease. A total of 168 (41%) patients developed cirrhosis (including 34 at the time of PSC diagnosis) after a median of 15.8 (95% CI 12.4, NA) years. The composite endpoint of death or liver transplantation occurred in 49 (12%) and 78 (19%) patients, respectively, with a median transplant-free survival of 13.4 (95% CI 12.2–15) years. Compared to the general population, PSC accounted for a 240-fold increased risk of development of cholangiocarcinoma (CCA) and CCA-related death. CCA risk was increased with older age of PSC diagnosis, presence of dominant stricture and colectomy. Compared to same-aged counterparts in the general population, PSC patients who were diagnosed at an older age or with longer disease duration had reduced relative survival.

Conclusion

In this large retrospective cohort study of PSC patients in Australia, increased age and time from diagnosis was associated with increased mortality and morbidity particularly from CCA and development of cirrhosis, necessitating need for liver transplant.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12072-022-10356-1.

Review of incidence and outcomes of treatment of cholangiocarcinoma in patients with primary sclerosing cholangitis

Primary sclerosing cholangitis (PSC) is a premalignant condition and a well-documented risk factor for cholangiocarcinoma (CCA) which is the most common malignancy in this setting and the leading cause of deaths in the recent years, with an increasing incidence. PSC-associated CCA has a geographical distribution that follows the incidence of PSC, with an observed ascending gradient from the Eastern to the Western and from the Southern to the Northern countries. It may arise at any location along the biliary tree but is most common in the perihilar area. Patients with PSC and intrahepatic or perihilar CCA are typically not suitable for liver resection, which is otherwise the treatment of choice with curative intent in patients with resectable tumours, providing a radical resection with clear margins can be achieved. This largely relates to the commonly advanced stage of liver disease at presentation, which allows consideration for liver resection only for a very limited number of suitable patients with PSC. On the other hand, remarkable progress has been reached in the last decades with the implementation of a protocol combining neoadjuvant chemoradiation and orthotopic liver transplantation (OLT) for the treatment of perihilar CCA, within specific criteria. Excellent results have been achieved particularly for PSC patients with this cancer, who seem to benefit the most from this treatment, having converted this into an accepted indication for transplantation and the standard of care in several experienced centres. Intrahepatic CCA as an indication for OLT remains controversial and has not been accepted given disappointing previous results. However, as recent studies have shown favourable outcomes in early intrahepatic CCA, it may be that under defined criteria, OLT may play a more prominent role in the future. Distal CCA in the context of PSC requires aggressive surgical treatment with curative intent, when feasible. This review provides insight about particular features of CCA in the setting of PSC, with a main focus on its incidence, considerations relating to its anatomical location and implications to treatment and outcomes, through the viewpoint of historical evolution of management, and future perspectives.

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.

α7-nAChR Knockout Mice Decreases Biliary Hyperplasia and Liver Fibrosis in Cholestatic Bile Duct-Ligated Mice

α7-nAChR is a nicotinic acetylcholine receptor [specifically expressed on hepatic stellate cells (HSCs), Kupffer cells, and cholangiocytes] that regulates inflammation and apoptosis in the liver. Thus, targeting α7-nAChR may be therapeutic in biliary diseases. Bile duct ligation (BDL) was performed on wild-type (WT) and α7-nAChR-/- mice. We first evaluated the expression of α7-nAChR by immunohistochemistry (IHC) in liver sections. IHC was also performed to assess intrahepatic bile duct mass (IBDM), and Sirius Red staining was performed to quantify the amount of collagen deposition. Immunofluorescence was performed to assess colocalization of α7-nAChR with bile ducts (costained with CK-19) and HSCs (costained with desmin). The mRNA expression of α7-nAChR, Ki-67/PCNA (proliferation), fibrosis genes (TGF-β1, fibronectin-1, Col1α1, and α-SMA), and inflammatory markers (IL-6, IL-1β, and TNF-α) was measured by real-time PCR. Biliary TGF-β1 and hepatic CD68 (Kupffer cell marker) expression was assessed using IHC. α7-nAChR immunoreactivity was observed in both bile ducts and HSCs and increased following BDL. α7-nAChR-/- BDL mice exhibited decreased (i) bile duct mass, liver fibrosis, and inflammation, and (ii) immunoreactivity of TGF-β1 as well as expression of fibrosis genes compared to WT BDL mice. α7-nAChR activation triggers biliary proliferation and liver fibrosis and may be a therapeutic target in managing extrahepatic biliary obstruction.

Smoking and risk of cholangiocarcinoma: a systematic review and meta-analysis

Previous studies evaluating the association between smoking and risk of cholangiocarcinoma (CCA) have yielded controversial results. We conducted a meta-analysis to evaluate the association based on available evidence. We searched the databases of Embase, PubMed and Cochrane Central Register of Controlled Trials from inception to April 11, 2017. Studies that investigated the association between smoking and risk of CCA were included. Pooled odds ratio (OR) estimates and 95% confidence intervals (CIs) were calculated using either a random-effects or a fixed-effects model. A total of 22 studies involving 324,333 participants were identified. The summary OR of CCA was 1.31 (95% CI, 1.15 to 1.51) for smokers versus nonsmokers. The increased risk was independent of diabetes mellitus, bilious tract stone disease, and liver cirrhosis. Smokers also had increased risk of intrahepatic CCA (12 studies; OR, 1.31; 95% CI, 1.06 to 1.63) and extrahepatic CCA (12 studies; OR, 1.32; 95% CI, 1.10 to 1.59) compared with nonsmokers. The results of our meta-analysis support the hypothesis that there is a moderate association between cigarette smoking and risk of CCA.

Anti-GP2 IgA autoantibodies are associated with poor survival and cholangiocarcinoma in primary sclerosing cholangitis

OBJECTIVE

Pancreatic autoantibodies (PABs), comprising antibodies against glycoprotein 2 (anti-GP2), are typically associated with complicated phenotypes in Crohn's disease, but have also been observed with variable frequencies in patients with UC. In a previous study, we observed a high frequency of primary sclerosing cholangitis (PSC) in patients with anti-GP2-positive UC. We therefore aimed to characterise the role of anti-GP2 in PSC.

DESIGN

In an evaluation phase, sera from 138 well-characterised Norwegian patients with PSC were compared with healthy controls (n=52), and patients with UC without PSC (n=62) for the presence of PABs by indirect immunofluorescence. Further, 180 German patients with PSC served as a validation cohort together with 56 cases of cholangiocarcinoma without PSC, 20 of secondary sclerosing cholangitis (SSC) and 18 of autoimmune hepatitis.

RESULTS

Anti-GP2 IgA specifically occurred at considerable rates in large bile duct diseases (cholangiocarcinoma=36%, PSC and SSC about 50%). In PSC, anti-GP2 IgA consistently identified patients with poor survival during follow-up (Norwegian/German cohort: p Log Rank=0.016/0.018). Anti-GP2 IgA was associated with the development of cholangiocarcinoma in both PSC cohorts, yielding an overall OR of cholangiocarcinoma in patients with anti-GP2 IgA-positive PSC of 5.0 (p=0.001). Importantly, this association remained independent of disease duration, bilirubin level and age.

CONCLUSIONS

Anti-GP2 IgA can be hypothesised as a novel marker in large bile duct diseases. In particular, in PSC, anti-GP2 IgA identified a subgroup of patients with severe phenotype and poor survival due to cholangiocarcinoma. Anti-GP2 IgA may therefore be a clinically valuable tool for risk stratification in PSC.

Primary sclerosing cholangitis in the Swiss Inflammatory Bowel Disease Cohort Study: prevalence, risk factors, and long-term follow-up

BACKGROUND AND AIM

Primary sclerosing cholangitis (PSC) represents the most common hepatobiliary extraintestinal manifestation of inflammatory bowel disease (IBD). We aimed to assess the prevalence of PSC in the Swiss Inflammatory Bowel Disease Cohort Study, to identify associated risk factors, and to describe the long-term evolution.

PATIENTS AND METHODS

Data of patients enrolled into the Swiss Inflammatory Bowel Disease Cohort Study were analyzed. Logistic regression modeling was performed to identify risk factors for PSC.

RESULTS

Among 2744 patients [1188 ulcerative colitis (UC); 1556 Crohn's disease (CD)], 57 had PSC (48 UC-PSC, nine CD-PSC). The prevalence of PSC was higher in UC compared with CD (4.04 vs. 0.58%, P<0.001). We identified the following significant independent risk factors for PSC in patients with UC: male sex [odds ratio (OR) 2.771, P=0.022], pancolitis (OR 2.855, P=0.011), nonsmoker at diagnosis (OR 9.253, P=0.030), and a history of appendicectomy (OR 4.114, P=0.019). During a median follow-up time of 74.8 months, four (7.0%) of PSC patients developed cholangiocarcinoma, six (10.5%) underwent liver transplantation, and five (8.8%) died. Survival of IBD-PSC patients was significantly worse compared with IBD patients without PSC (P=0.001). UC-PSC patients developed significantly more frequently colorectal cancer compared with UC patients without PSC (2/48 vs. 9/1440, P=0.017).

CONCLUSION

Approximately 4% of UC patients and 0.6% of CD patients had PSC. Male sex, pancolitis, nonsmoker status, and a history of appendicectomy were significantly associated with PSC. PSC is associated with considerable morbidity and mortality in the long term.

Health-related quality of life among patients with primary sclerosing cholangitis

BACKGROUND & AIMS

To assess health-related quality of life (HRQoL) of patients with primary sclerosing cholangitis (PSC), and to compare it with that of the general population. Also, to examine changes in HRQoL in newly diagnosed PSC patients at a follow-up 1-2 years later, and to compare their HRQoL with HRQoL of newly diagnosed inflammatory bowel disease (IBD) patients. Furthermore, sources of and need for disease-related information among PSC patients were surveyed.

METHODS

Primary sclerosing cholangitis patients filled in the survey questionnaire when attending an endoscopic retrograde cholangiography examination. The 15D served as a general HRQoL instrument. The follow-up questionnaire was mailed to the newly diagnosed patients 1-2 years later.

RESULTS

No significant difference was seen in 15D scores between PSC patients and general population, but the dimensions of excretion (P < 0.001), depression (P = 0.003), distress (P = 0.003) and vitality (P = 0.005) were significantly lower in PSC. Age and symptoms affected HRQoL but severity of biliary changes did not. Those with newly diagnosed IBD had lower 15D scores than those with PSC. No significant changes were observed in 15D scores of new PSC patients in the follow-up. Many patients were dissatisfied with information received.

CONCLUSION

Newly diagnosed PSC patients have better HRQoL than do IBD patients, and no significant HRQoL changes were observed in the mean follow-up of 1.58 years after PSC diagnosis. ERC findings did not correlate with HRQoL or symptoms. HRQoL of PSC patients was mostly comparable with that of general population, but special attention should be paid to patients' psychological well-being.

Primary sclerosing cholangitis: diagnosis and treatment

BACKGROUND

Primary sclerosing cholangitis (PSC) is a chronic cholestatic liver disease that involves progressive destruction of the bile ducts. Its prevalence is 4 to 16 cases per 100,000 persons. Its incidence has risen over the last 20 years, with a more than 35% increase in the last 10 years alone. PSC tends to arise in patients with chronic inflammatory bowel diseases. It is associated with an increased risk of various types of cancer (13%-14%), most prominently cholangiocellular carcinoma (CCC).

METHOD

This review is based on a selective search in PubMed for original articles, meta-analyses, and review articles about PSC that appeared from January 1980 to May 2013.

RESULTS

The diagnosis is generally established with a bile duct imaging study--typically, magnetic resonance cholangiopancreaticography (MRCP): this test is more than 80% sensitive and more than 90% specific for the diagnosis of PSC. The time from diagnosis to death or liver transplantation is 12 to 18 years, and the risk that a patient with PSC will die of cancer is 40% to 58%. Options for drug treatment are limited. Randomized, controlled trials have not shown any improvement of outcomes from the administration of ursodeoxycholic acid (UDCA). Interventional endoscopy is used to treat dominant stenoses and cholangitis, even though this method of treatment is supported only by low-level evidence. Liver transplantation results in a 10-year survival rate above 80%.

CONCLUSION

There is no causally directed treatment for PSC. Early diagnosis, complication management, and the evaluation of an optimally timed liver transplantation are the main determinants of outcome.

Role of endoscopy in primary sclerosing cholangitis

Primary sclerosing cholangitis is a chronic cholestatic liver disease characterized by progressive inflammation affecting the entire biliary tree and leading to biliary symptoms and complications. It is of unclear etiology and is usually associated with inflammatory bowel diseases. Despite advances in modern medicine, treatment options remain very limited, and without liver transplantation, survival rates are reduced. We aim in this review to highlight available endoscopic methods to evaluate, diagnose, and manage symptoms and complications associated with this disease, including diagnosis of cholangiocarcinoma and endoscopic palliative treatment for advanced cholangiocarcinoma not amenable to surgical resection.

[Patient selection and indications for liver transplantation]

Liver transplantation represents an established component of the therapeutic repertoire for irreversible chronic liver diseases. Liver transplantation is confronted by a shortage of donor allografts as well as by an increasing overall number of potentially useful indications, which leads to a rationing of this therapeutic option. Since December 2006 the priority for liver transplantation is determined by the model for end-stage liver disease (MELD) and not by the length of waiting time. The evaluation of indications which are prioritized according to laboratory values (serum creatine, serum bilirubin and coagulation) and the so-called standard exception categories which have to fulfil specific criteria place increased demands on the interdisciplinary transplantation team, on the evaluation for liver transplantation and the prediction of the success of transplantation required by the Transplantation Act. The establishment and implementation of robust, objective and transparent systems to assess not only preoperative priorities but also postoperative benefits represents a major challenge for transplantation medicine.

Population-based epidemiology, malignancy risk, and outcome of primary sclerosing cholangitis

Extensive population-based studies are much needed to accurately establish epidemiology and disease course in patients with primary sclerosing cholangitis (PSC). We aimed to obtain population-based prevalence and incidence figures, insight in disease course with regard to survival, liver transplantation (LT), and occurrence of malignancies, as well as risk factors thereof. Four independent hospital databases were searched in 44 hospitals in a large geographically defined area of the Netherlands, comprising 50% of the population. In addition, all PSC patients in the three Dutch liver transplant centers and all inflammatory bowel disease (IBD) patients in the adherence area of a large district hospital were identified. All medical records were reviewed on-site, verifying diagnosis. Five hundred and ninety PSC patients were identified, resulting in an incidence of 0.5 and a point prevalence of 6.0 per 100,000. Median follow up was 92 months. Estimated median survival from diagnosis until LT or PSC-related death in the entire cohort was 21.3 years, as opposed to 13.2 years in the combined transplant centers cohort (n = 422; P < 0.0001). Colorectal carcinoma (CRC) risk was 10-fold increased, as compared to ulcerative colitis controls, and developed at a much younger age (39 years; range, 26-64), compared to IBD controls (59 years; range, 34-73; P = 0.019). Colonoscopic surveillance was associated with significantly better outcome.

CONCLUSION

This study exemplifies that, for relatively rare diseases, it is paramount to collect observational data from large, population-based cohorts, because incidence and prevalence rates of PSC are markedly lower and survival much longer than previously reported. The selection of a bias-free, population-based cohort showed a significantly longer survival, compared to the tertiary referral cohort. CRC can develop at an early age, warranting surveillance from time of PSC diagnosis.

Antineutrophil cytoplasmic antibodies in bile are associated with disease activity in primary sclerosing cholangitis

OBJECTIVE. Primary sclerosing cholangitis (PSC) is an autoimmune cholestatic liver disease of unknown etiology. The role of antineutrophil cytoplasmic antibodies (ANCAs) in the serum of patients with PSC remains unclear. We hypothesized that ANCA may be detectable in bile, potentially providing diagnostic and prognostic information. METHODS. Serum and bile were prospectively collected during endoscopic retrograde cholangiography (ERC) in 72 patients with PSC and other non-PSC obstructive biliary diseases. ANCA measurements were performed by indirect immunofluorescence (IIF). RESULTS. Immunoglobulin G (IgG) ANCA was detected significantly more often in the bile of PSC patients (15/39; 38%) than without (2/33; 6%) (p = 0.001). IgG ANCA in bile was associated with a ten times higher risk of PSC (p = 0.005). In addition, IgG ANCA positivity in bile was associated with the presence of dominant strictures (p = 0.03), cholangiographic severity (p = 0.004), number of ERC (p = 0.01) and interventions performed (p = 0.03). However, IgG ANCA in bile did not correlate with transplantation, cholangiocarcinoma or death. No association was observed between ANCA positivity in sera and ANA and ASCA positivity in sera or bile with the above-mentioned clinical features. CONCLUSIONS. The presence of ANCA in the bile of patients with PSC is a novel finding and highly suggestive of PSC. Biliary IgG ANCA correlates with the severity of bile duct strictures and the ensuing number of ERCs and interventions. Therefore, a positive ANCA status in bile may serve as a diagnostic and prognostic marker of the disease progression and biliary complications.

Chronic nicotine exposure stimulates biliary growth and fibrosis in normal rats

BACKGROUND

Epidemiological studies have indicated smoking to be a risk factor for the progression of liver diseases. Nicotine is the chief addictive substance in cigarette smoke and has powerful biological properties throughout the body. Nicotine has been implicated in a number of disease processes, including increased cell proliferation and fibrosis in several organ systems.

AIMS

The aim of this study was to evaluate the effects of chronic administration of nicotine on biliary proliferation and fibrosis in normal rats.

METHODS

In vivo, rats were treated with nicotine by osmotic minipumps for two weeks. Proliferation, α7-nicotinic receptor and profibrotic expression were evaluated in liver tissue, cholangiocytes and a polarized cholangiocyte cell line (normal rat intrahepatic cholangiocyte). Nicotine-dependent activation of the Ca(2+)/IP3/ERK 1/2 intracellular signalling pathway was also evaluated in normal rat intrahepatic cholangiocyte.

RESULTS

Cholangiocytes express α7-nicotinic receptor. Chronic administration of nicotine to normal rats stimulated biliary proliferation and profibrotic gene and protein expression such as alpha-smooth muscle actin and fibronectin 1. Activation of α7-nicotinic receptor stimulated Ca(2+)/ERK1/2-dependent cholangiocyte proliferation.

CONCLUSION

Chronic exposure to nicotine contributes to biliary fibrosis by activation of cholangiocyte proliferation and expression of profibrotic genes. Modulation of α7-nicotinic receptor signalling axis may be useful for the management of biliary proliferation and fibrosis during cholangiopathies.

Successful treatment of recurrent primary sclerosing cholangitis after orthotopic liver transplantation with oral vancomycin

Primary sclerosing cholangitis (PSC) is a progressive, cholestatic disease of the liver that is marked by inflammation of the bile ducts and damage to the hepatic biliary tree. Approximately 60–70% of patients also have inflammatory bowel disease and progression of PSC can lead to ulcerative colitis and cirrhosis of the liver. Due to limited understanding of the etiology and mechanism of PSC, the only existing treatment option is orthotopic liver transplantation (OLT); however, recurrence of PSC, after OLT is estimated to be between 5% and 35%. We discuss the successful treatment of a pediatric patient, with recurrent PSC, after OLT with oral Vancomycin.

Mechanisms for nicotine in the development and progression of gastrointestinal cancers

Long-term smoking is major risk factor for a variety of cancers, including those of the gastrointestinal (GI) tract. Historically, nicotine and its derivatives are well known for their role in addiction, and have more recently been documented for their carcinogenic role in a number of human cancers. The cellular and molecular pathways activated by nicotine mimic physiological and environmental carcinogenesis in cancers throughout the GI tract potentiating cancer growth and/or inducing the formation of cancer on their own. Thus, it is important to unlock the carcinogenic mechanisms induced by nicotine in these systems, and underscore nicotine's potential as an environmental hazard. This review outlines the specific pathways demonstrated to mediate nicotine's carcinogenic mechanism in the GI tract. The abundance of cell and animal evidence calls for increased epidemiologic and case-control evaluation of nicotine's role in cancer.

Mortality and cancer risk related to primary sclerosing cholangitis in a Swedish population-based cohort

BACKGROUND

Population-based studies on the epidemiology of primary sclerosing cholangitis (PSC) are sparse.

AIMS

To investigate mortality and risk of cancer, and to identify risk factors for hepatobiliary cancer and the combined end-point liver related death or liver transplantation (OLT) in a population-based PSC cohort in Västra Götaland, Sweden.

METHODS

Primary sclerosing cholangitis cases were identified in diagnostic registries. Case validation and follow up was provided through individual review of case files and linkage to the Swedish Cancer and Cause of Death registries. Standardized mortality ratio (SMR) and standardized incidence ratio (SIR) for cancer were calculated in relation to the background population. Cox's proportional hazards analysis was used to calculate crude and adjusted relative risks (RRs).

RESULTS

A total of 199 PSC patients were identified between 1992 and 2005. SMR in the PSC cohort was 4.20 (95% confidence interval (CI), 3.01-5.69). SIR for hepatobiliary cancer, cholangiocarcinoma and colorectal cancer were 177 (110-271), 868 (505-1390) and 2.87 (0.33-10.4) respectively. Age (RR=1.25 (1.01-1.53) per decade), female gender (RR=2.01 (1.09-3.72)), cholangitis (RR=2.56 (1.20-5.64)) and bilirubin (RR=3.95 (1.96-10.75) highest vs lowest quartile) were associated with the risk of liver related death or OLT. Age was associated with the risk of hepatobiliary cancer (RR 1.40 (1.01-1.95) per decade).

CONCLUSIONS

Primary sclerosing cholangitis was associated with a four-fold increase in mortality in this population-based study. In accordance with previous studies, the risk of hepatobiliary cancer was dramatically increased. However, the increased risk of colorectal cancer reported in previous studies could not be confirmed.

Hepatobiliary disorders and complications of inflammatory bowel disease

One of typical examples of liver-gut cross talk is the interaction and impact of inflammatory bowel disease (IBD) and hepatobiliary (HB) abnormalities on each other's disease course. There are several layers of association between IBD and HB diseases: (i) HB diseases and IBD share pathogenetic mechanisms; (ii) HB diseases parallel structural and pathophysiological changes seen with IBD; and (iii) hepatic toxicity is associated with medical therapy for IBD. Interdisciplinary approach, involving gastroenterologists, hepatologists and, in advanced cases, general, colorectal, and liver transplant surgeons, is advocated.

Hepatopancreatobiliary manifestations and complications associated with inflammatory bowel disease

Diseases involving the hepatopancreatobiliary (HPB) system are frequently encountered in patients with inflammatory bowel disease (IBD). Hepatobiliary manifestations constitute some of the most common extraintestinal manifestations of IBD. They appear to occur with similar frequency in patients with Crohn's disease or ulcerative colitis. HPB manifestations may occur in following settings: 1) disease possibly associated with a shared pathogenetic mechanism with IBD including primary sclerosing cholangitis (PSC), small-duct PSC/pericholangitis and PSC/autoimmune hepatitis overlap, acute and chronic pancreatitis related to IBD; 2) diseases which parallel structural and physiological changes seen with IBD, including cholelithiasis, portal vein thrombosis, and hepatic abscess; and 3) diseases related to adverse effects associated with treatment of IBD, including drug-induced hepatitis, pancreatitis (purine-based agents), or liver cirrhosis (methotrexate), and reactivation of hepatitis B, and biologic agent-associated hepatosplenic lymphoma. Less common HPB manifestations that have been described in association with IBD include autoimmune pancreatitis (AIP), IgG4-associated cholangitis (IAC), primary biliary cirrhosis (PBC), fatty liver, granulomatous hepatitis, and amyloidosis. PSC is the most significant hepatobiliary manifestation associated with IBD and poses substantial challenges in management requiring a multidisciplinary approach. The natural disease course of PSC may progress to cirrhosis and ultimately require liver transplantation in spite of total proctocolectomy with ileal-pouch anal anastomosis. The association between AIP, IAC, and elevated serum IgG4 in patients with PSC is intriguing. The recently reported association between IAC and IBD may open the door to investigate these complex disorders. Further studies are warranted to help understand the pathogenesis of HPB manifestations associated with IBD, which would help clinicians better manage these patients. An interdisciplinary approach, involving gastroenterologists, hepatologists, and, in advanced cases, general, colorectal, and transplant surgeons is advocated.

[Liver transplantation: indications and results]

After around 64,000 transplantations in Europe since 1988 liver transplantation has emerged as a standard treatment option for otherwise incurable chronic liver diseases. Cirrhosis of different etiologies represents the most frequent transplant indication. Overall survival in this group amounts to 72% after 5 years, and 62% after 10 years. In Germany, the main indications include alcoholic liver cirrhosis, tumors with increasing numbers in recent years, as well as viral diseases leading to cirrhosis. Since December 2006 the priority for liver transplantation is determined by the model for end stage liver disease (MELD) and not by the length of waiting time. MELD is a statistical model based on serum creatinine, serum bilirubin and coagulation, which describes the probability of 3-month mortality of a potential transplant candidate. Not all liver diseases are adequately represented by MELD necessitating the additional use of a defined number of standard exceptions that have been last updated in 2008. As a consequence of these developments indications, selection of recipients and the management of the waiting list have seen profound change.

Perihilar lymph nodes in patients with primary sclerosing cholangitis with and without cholangiocellular carcinoma

OBJECTIVE

Enlarged perihilar lymph nodes have been described in patients with primary sclerosing cholangitis (PSC). The aim of the study was to determine the clinical relevance of perihilar lymph nodes in PSC patients with and without cholangiocellular carcinoma (CCC).

MATERIAL AND METHODS

The status of perihilar lymph nodes was investigated in 117 patients with PSC using "high-end" ultrasound. Thirty-five of the 117 PSC patients had histologically proven CCC. Lymph node status was correlated with the presence of CCC and inflammatory bowel disease (IBD).

RESULTS

Seventy-three percent of PSC patients without CCC and 86% of patients with CCC had enlarged perihilar lymph nodes (NS). In CCC patients, the width of lymph nodes was significantly larger (12+/-6 mm versus 8+/-4 mm; p=0.0001), and the length:width ratio (2.15+/-0.7:1 versus 2.5+/-0.6:1; p=0.004) of the lymph nodes was significantly lower. Thirty-seven percent of PSC patients without CCC and 57% of patients with PSC and CCC had multiple perihilar lymph nodes (p=0.04). In all patients, the presence versus absence of IBD had no influence on the number (84% versus 74%,) and size of perihilar lymph nodes (length: 21+/-10 mm versus 19+/-7 mm). Lymph node status did not correlate with the number of episodes of cholangitis.

CONCLUSIONS

Enlarged perihilar lymph nodes are characteristic of patients with PSC. Since perihilar lymph nodes are not predictive of the presence of complicating CCC, such patients should not be excluded from liver transplantation.

The challenges in primary sclerosing cholangitis--aetiopathogenesis, autoimmunity, management and malignancy

Primary sclerosing cholangitis (PSC) is a chronic cholestatic liver disease, characterized by progressive inflammation and fibrosis of the bile ducts, resulting in biliary cirrhosis and is associated with a high risk of cholangiocarcinoma. The majority of patients are young, male and have coexisting inflammatory bowel disease. PSC is found with a prevalence of 10/100,000 in Northern European populations. The pathophysiology of PSC is a complex multistep process including immunological mechanisms, immunogenetic susceptibility and disorders of the biliary epithelia. The diagnosis is primarily based on endoscopic cholangiography although magnetic resonance imaging is increasingly used; biochemistry and immunoserology as well as histology play only a minor role. Due to the high risk of developing cholangiocarcinoma and also other tumours of the GI tract, surveillance strategies are essential, however they have yet to be established and evaluated. Biochemical parameters, clinical risk factors, endoscopic procedures and imaging techniques contribute to the early identification of patients at risk. Since medical therapy of PSC with ursodeoxycholic acid does not improve survival, to date, liver transplantation is the only option with a cure potential; if transplantation is accurately timed, transplanted PSC patients have an excellent rate of survival. However if cholangiocarcinoma is detected, a curative treatment is not possible in the majority of cases. The present review critically summarizes the current knowledge on the aetiopathogenesis of PSC and gives an overview of the diagnostic approaches, surveillance strategies and therapeutic options. Primary sclerosing cholangitis is a disease of unknown aetiology and without any further curative treatment options apart from liver transplantation. Therefore it may be regarded as the greatest challenge in hepatology today.

Current diagnosis and management of primary sclerosing cholangitis

Primary sclerosing cholangitis (PSC) is an important liver disease with major morbidity and mortality. The diagnosis of PSC is confirmed by magnetic resonance cholangiopancreaticography, and endoscopic retrograde cholangiopancreaticography is performed in patients needing therapeutic endoscopy. As a result of the unknown cause of the disease, current medical therapies are unsatisfactory. Nevertheless, high-dose ursodeoxycholic acid should be recommended for treatment of PSC patients because there is a trend toward increased survival. Dominant bile duct stenoses should be treated endoscopically. However, liver transplantation continues to be the only therapeutic option for patients with advanced disease. Estimation of prognosis and timing of liver transplantation should be determined individually for each PSC patient on the basis of all results. The diagnosis and treatment of cholangiocarcinoma (CC) still remain a challenge in PSC patients. Early diagnosis of CC certainly is a prerequisite for successful treatment with surgical resection or innovative strategies such as neoadjuvant radiochemotherapy with subsequent orthotopic liver transplantation. Therefore, endoscopic techniques such as cholangioscopy and/or intraductal ultrasound may be useful diagnostic tools in patients with stenoses suspicious for malignancy.

An update on primary sclerosing cholangitis

PURPOSE OF REVIEW

Primary sclerosing cholangitis is a chronic cholestatic liver disease characterized by strictures of the biliary tree complicated by cirrhosis and cholangiocarcinoma. It is immune mediated, although the precise aetiology remains unknown.

RECENT FINDINGS

The research into aetiology, genetic associations, pathogenesis, epidemiology, diagnosis of cholangiocarcinoma and medical treatments are discussed.

SUMMARY

Multiple gene polymorphisms and human leucocyte antigen haplotype associations with primary sclerosing cholangitis have been investigated. Common inflammatory bowel disease associated polymorphisms and ulcerative colitis associated human leucocyte antigen haplotypes are not associated with primary sclerosing cholangitis. Biliary epithelial cells may mediate their own destruction by exaggerating innate and adaptive immune responses to bacterial products in the liver. The natural history of large and small duct primary sclerosing cholangitis has been reviewed. Positron emission tomography may be a useful adjunct to current imaging modalities in the pretransplant assessment of patients to exclude cholangiocarcinoma. Ursodeoxycholic acid remains the most studied medical treatment for primary sclerosing cholangitis; pilot studies suggest a possible role for tacrolimus and silymarin, however further studies are required.

Transpapillary intraductal ultrasound in the evaluation of dominant bile duct stenoses in patients with primary sclerosing cholangitis

OBJECTIVE

Primary sclerosing cholangitis (PSC) is associated with the development of cholangiocarcinoma (CC) in approximately 9% of patients. Neither cholangiography nor endoscopic tissue sampling can reliably distinguish between CC and benign dominant bile duct stenosis. The aim of the present study was to assess the value of intraductal ultrasonography (IDUS) in distinguishing between benign and malignant dominant stenoses in PSC patients.

MATERIAL AND METHODS

Forty PSC patients with dominant bile duct stenoses were studied prospectively. Transpapillary IDUS and endoscopic tissue sampling were performed in addition to endoscopic retrograde cholangiography (ERC). Cholangiography and IDUS findings were classified as malignant or benign by the investigators. Final diagnosis of malignant stenosis was based on positive histology and/or cytology, whereas a benign character was assumed in cases of negative tissue sampling and uneventful extended clinical follow-up.

RESULTS

Eight PSC patients (20%) had dominant bile duct stenoses caused by CC, whereas 32 out of 40 patients (80%) had benign dominant bile duct stenoses. IDUS was significantly superior to ERC for detection of malignancy in terms of sensitivity (87.5% versus 62.5%, p=0.05), specificity (90.6% versus 53.1%, p<0.001), accuracy (90% versus 55%, p<0.001), positive predictive value (70% versus 25%, p<0.001), and negative predictive value (96.7% versus 85%, p=0.049).

CONCLUSIONS

Transpapillary IDUS significantly increases the ability to distinguish malignant from benign dominant bile duct stenoses in patients with PSC.

Sclerosing cholangitis

PURPOSE OF REVIEW

Primary sclerosing cholangitis is a chronic cholestatic liver disease characterized by strictures of the biliary tree complicated by cirrhosis and cholangiocarcinoma. It is immune mediated, although the precise aetiology remains unknown.

RECENT FINDINGS

Research into etiopathogenesis and epidemiology, diagnosis of cholangiocarcinoma, associations with inflammatory bowel disease and autoimmune pancreatitis, and medical therapy are discussed.

SUMMARY

Multiple gene polymorphisms associated with primary sclerosing cholangitis have been investigated. Common inflammatory bowel disease-associated polymorphisms do not confer any susceptibility to primary sclerosing cholangitis; the role of intercellular adhesion molecule-1 gene polymorphisms and CCR5 mutations remain unclear. Elevated IgG4 has been demonstrated in a subgroup of primary sclerosing cholangitis patients, which may indicate an overlap with autoimmune pancreatitis and possible responsiveness to steroids. Biliary brush cytology may assist in diagnosis of cholangiocarcinoma, although further clinical indicators are required. Animal studies suggest the superiority of 24-norursodeoxycholic acid over ursodeoxycholic acid in reducing histological disease progress; translational studies in humans are now required.