Serum and bile biomarkers for cholangiocarcinoma

Refinement of paramagnetic bead-based digestion protocol for automatic sample preparation using an artificial neural network

Despite technological advances in the proteomics field, sample preparation still represents the main bottleneck in mass spectrometry (MS) analysis. Bead-based protein aggregation techniques have recently emerged as an efficient, reproducible, and high-throughput alternative for protein extraction and digestion. Here, a refined paramagnetic bead-based digestion protocol is described for Opentrons® OT-2 platform (OT-2) as a versatile, reproducible, and affordable alternative for the automatic sample preparation for MS analysis. For this purpose, an artificial neural network (ANN) was applied to maximize the number of peptides without missed cleavages identified in HeLa extract by combining factors such as the quantity (μg) of trypsin/Lys-C and beads (MagReSyn® Amine), % (w/v) SDS, % (v/v) acetonitrile, and time of digestion (h). ANN model predicted the optimal conditions for the digestion of 50 μg of HeLa extract, pointing to the use of 2.5% (w/v) SDS and 300 μg of beads for sample preparation and long-term digestion (16h) with 0.15 μg Lys-C and 2.5 μg trypsin (≈1:17 ratio). Based on the results of the ANN model, the manual protocol was automated in OT-2. The performance of the automatic protocol was evaluated with different sample types, including human plasma, Arabidopsis thaliana leaves, Escherichia coli cells, and mouse tissue cortex, showing great reproducibility and low sample-to-sample variability in all cases. In addition, we tested the performance of this method in the preparation of a challenging biological fluid such as rat bile, a proximal fluid that is rich in bile salts, bilirubin, cholesterol, and fatty acids, among other MS interferents. Compared to other protocols described in the literature for the extraction and digestion of bile proteins, the method described here allowed identify 385 unique proteins, thus contributing to improving the coverage of the bile proteome.

Establishment and validation of a nomogram containing cytokeratin fragment antigen 21-1 for the differential diagnosis of intrahepatic cholangiocarcinoma and hepatocellular carcinoma

Background

Our study aimed to develop a nomogram incorporating cytokeratin fragment antigen 21-1 (CYFRA21-1) to assist in differentiating between patients with intrahepatic cholangiocarcinoma (ICC) and hepatocellular carcinoma (HCC).

Methods

A total of 487 patients who were diagnosed with ICC and HCC at Qilu Hospital of Shandong University were included in this study. The patients were divided into a training cohort and a validation cohort based on whether the data collection was retrospective or prospective. Univariate and multivariate analyses were employed to select variables for the nomogram. The discrimination and calibration of the nomogram were evaluated using the area under the receiver operating characteristic curve (AUC) and calibration plots. Decision curve analysis (DCA) was used to assess the nomogram's net benefits at various threshold probabilities.

Results

Six variables, including CYFRA21-1, were incorporated to establish the nomogram. Its satisfactory discriminative ability was indicated by the AUC (0.972 for the training cohort, 0.994 for the validation cohort), sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) values. The Hosmer-Lemeshow test and the calibration plots demonstrated favorable consistency between the nomogram predictions and the actual observations. Moreover, DCA revealed the clinical utility and superior discriminative ability of the nomogram compared to the model without CYFRA21-1 and the model consisting of the logarithm of alpha-fetoprotein (Log AFP) and the logarithm of carbohydrate antigen 19-9 (Log CA19-9). Additionally, the AUC values suggested that the discriminative ability of Log CYFRA21-1 was greater than that of the other variables used as diagnostic biomarkers.

Conclusions

This study developed and validated a nomogram including CYFRA21-1, which can aid clinicians in the differential diagnosis of ICC and HCC patients.

High Bile Titer and High Bile to Serum Ratio of CYFRA 21 - 1 Reliably Discriminate Malignant Biliary Obstruction Caused by Cholangiocarcinoma

INTRODUCTION

Previously we demonstrated that elevated serum CYFRA 21 - 1 is a reliable diagnostic and prognostic biomarker for biliary tract cancers. This study aims to explore the diagnostic performance of bile CYFRA 21 - 1 (bCYFRA 21 - 1) in discriminating malignant biliary obstruction (MBO) caused by cholangiocarcinoma (CCA).

METHODS

77 CCA patients ((17 intrahepatic CCA (iCCA), 49 perihilar CCA (pCCA) and 11 distal CCA (dCCA)) and 43 benign patients with biliary obstruction were enrolled. Serum and bile levels of CYFRA 21 - 1, carcinoembryonic antigen (CEA) and carbohydrate antigen 19 - 9 (CA19-9) were quantified. Diagnostic performances of these biomarkers were estimated by receiver operator characteristic curves. Subgroups analysis of these tumor markers among CCA subtypes was performed.

RESULTS

High bCYFRA 21 - 1 (cut-off value of 59.25 ng/mL with sensitivity of 0.889 and specificity of 0.750) and high bile to serum ratio of CYFRA 21 - 1 (b/sCYFRA 21 - 1, cut-off value of 31.55 with sensitivity of 0.741 and specificity of 0.778) achieved better diagnostic performance than any other biomarker in discriminating MBO. Subgroup analysis revealed that bCYFRA 21 - 1 was significantly elevated in all CCA subtypes; moreover b/sCYFRA 21 - 1 was upregulated in pCCA and dCCA (the mean b/sCYFRA 21 - 1 of pCCA was highest among CCA subtypes: 57.90, IQR 29.82-112.27).

CONCLUSIONS

Both high biliary CYFRA 21 - 1 and high bile to serum ratio of CYFRA 21 - 1 were reliable diagnostic biomarkers for MBO caused by CCA.

Terminal fucosylation of haptoglobin in cancer-derived exosomes during cholangiocarcinoma progression

Background

Cholangiocarcinoma (CCA) is a silent tumor with a high mortality rate due to the difficulty of early diagnosis and prediction of recurrence even after timely surgery. Serologic cancer biomarkers have been used in clinical practice, but their low specificity and sensitivity have been problematic. In this study, we aimed to identify CCA-specific glycan epitopes that can be used for diagnosis and to elucidate the mechanisms by which glycosylation is altered with tumor progression.

Methods

The serum of patients with various cancers was fractioned into membrane-bound and soluble components using serial ultracentrifugation. Lectin blotting was conducted to evaluate glycosylation. Proteins having altered glycosylation were identified using proteomic analysis and further confirmed using immunoblotting analysis. We performed HPLC, gene analysis, real-time cargo tracking, and immunohistochemistry to determine the origin of CCA glycosylation and its underlying mechanisms. Extracellular vesicles (EV) were isolated from the sera of 62 patients with CCA at different clinical stages and inflammatory conditions and used for glycan analysis to assess their clinical significance.

Results

The results reveal that glycosylation patterns between soluble and membrane-bound fractions differ significantly even when obtained from the same donor. Notably, glycans with α1-3/4 fucose and β1-6GlcNAc branched structures increase specifically in membrane-bound fractions of CCA. Mechanically, it is primarily due to β-haptoglobin (β-Hp) originating from CCA expressing fucosyltransferase-3/4 (FUT 3/4) and N-acetylglucosaminyltransferase-V (MGAT5). Newly synthesized β-Hp is loaded into EVs in early endosomes via a KFERQ-like motif and then secreted from CCA cells to induce tumor progression. In contrast, β-Hp expressed by hepatocytes is secreted in a soluble form that does not affect CCA progression. Moreover, evaluation of EV glycosylation in CCA patients shows that fucosylation level of EV-Hp gradually increases with tumor progression and decreases markedly when the tumors are eliminated by surgery.

Conclusion

This study suggests that terminal fucosylation of Hp in cancer-derived exosomes can be a novel glycan marker for diagnosis and prognosis of CCA. These findings highlight the potential of glycan analysis in different fractions of serum for biomarker discover for other diseases. Further research is needed to understand the role of fucosylated EVs on CCA progression.

Molecular diagnosis of pancreatobiliary tract cancer by detecting mutations and methylation changes in bile samples

BACKGROUND

Patients with pancreatobiliary tract cancer usually have a poor clinical outcome, with a 5-year overall survival rate below 20%. This is mainly associated with the late diagnosis. In addition, the standard-of-care for patients with malignant biliary stenosis involves a major surgery, the Whipple procedure. An accurate preoperative diagnosis, including differentiation from benign diseases, is critical to avoid unnecessary treatment. Here we developed BileScreen, a sensitive detection modality for the diagnosis of pancreatobiliary tract cancer based on massively parallel sequencing mutation and methylation changes in bile samples.

METHODS

A total of 338 patients, from five hospitals in China, with pancreatobiliary system disorders were enrolled in this study between November 2018 and October 2020, and 259 were included for the analysis of BileScreen. We profiled 23 gene mutations and 44 genes with methylation modifications in parallel from bile samples, and set up a model for the detection of malignancy based on multi-level biomarkers.

FINDINGS

We applied the BileScreen assay in a training cohort (n = 104) to set up the model and algorithm. The model was further evaluated in a validation cohort (n = 105), resulting in 92% sensitivity and 98% specificity. The performance of BileScreen was further assessed in a prospective test cohort (n = 50) of patients diagnosed with suspicious or negative pathology by endoscopic retrograde cholangiopancreatography and were confirmed in follow-up. BileScreen yielded 90% sensitivity and 80% specificity, and outcompeted serum carbohydrate antigen 19-9 in detecting pancreatobiliary tract cancer in all three cohorts, especially in terms of specificity.

INTERPRETATION

Taken together, BileScreen has the ability to interrogate mutations and methylation changes in bile samples in parallel, thus rendering it a potentially sensitive detection method to help in the diagnosis of pancreatobiliary tract cancer in a safe, convenient and less-invasive manner.

FUNDING

This study was supported by the Capital's Funds for Health Improvement and Research (2020-2-4025 to S.H.), the National Natural Science Foundation of China (81972311 to H.Z.), CAMS Innovation Fund for Medical Sciences (CIFMS) (2017-12M-4-002 to H.Z.), the CAMS Innovation Fund for Medical Sciences(CIFMS) (2021-I2M-1-066 to CJQ), the Non-profit Central Research Institution Fund of Chinese Academy of Medical Sciences (2019PT310026 to H.Z.) and Sanming Project of Medicine in Shenzhen (SZSM202011010 to H.Z.).

Elevated Serum Levels of CCL23 Are Associated with Poor Outcome after Resection of Biliary Tract Cancer

Background

Surgical tumor resection is the only potentially curative treatment option for patients with biliary tract cancer (BTC). However, 5-year survival rates are still below 50% mainly due to tumor recurrence. The preoperative identification of ideal surgical candidates has remained a major challenge and easily accessible algorithms including parameters of the individual tumor biology are missing. Chemokine (C-C motif) ligand 23 (CCl23) has been associated with tumor progression in hepatocellular carcinoma (HCC), but its role in the context of BTC is largely unknown. Here, we evaluated circulating levels of CCL23 as potential diagnostic and prognostic biomarker in patients with resectable BTC.

Methods

CCl23 serum levels were analyzed by multiplex immunoassay in a cohort of 119 BTC patients receiving surgical tumor resection as well as 50 healthy control samples and 11 patients with primary sclerosing cholangitis (PSC).

Results

Baseline serum CCL23 levels were significantly elevated in BTC patients compared to PSC patients as well as healthy controls. CCL23 increased the diagnostic sensitivity and specificity of established tumor markers including CA19-9 and correlated with patients' age and makers of systemic inflammation. Elevated preoperative CCL23 levels were associated with a significantly impaired postoperative outcome. BTC patients with a preoperative CCL23 level above the optimal prognostic cut-off value of 702.4 pg/ml showed a median OS of only 110 days compared to 501 days for patients with low initial CCL23 levels. The prognostic value of circulating CCL23 was confirmed in Cox-regression analysis.

Conclusion

Serum levels of CCL23 are elevated in patients with BTC, and high preoperative CCL23 levels were associated with an impaired postoperative survival. CCL23 serum levels could help to identify the ideal surgical candidates for BTC resection in the future.

Surgical Treatment of Distal Cholangiocarcinoma

Distal cholangiocarcinoma (dCCA) is a rare malignancy arising from the epithelial cells of the distal biliary tract and has a poor prognosis. dCCA is often clinically silent and patients commonly present with locally advanced and/or distant disease. For patients identified with early stage, resectable disease, surgical resection with negative margins remains the only curative treatment strategy available. However, despite appropriate treatment and diligent surveillance, risk of recurrence remains high with nearly 50% of patients experiencing recurrence at 5 years subsequent to surgical resection; therefore, it is prudent to continue to optimize neoadjuvant and adjuvant therapies in order to reduce the risk of recurrence and improve overall survival. In this review, we discuss the clinical presentation, workup and surgical treatment of dCCA.

Development and validation of a machine learning-based nomogram for prediction of intrahepatic cholangiocarcinoma in patients with intrahepatic lithiasis

BACKGROUND

Accurate diagnosis of intrahepatic cholangiocarcinoma (ICC) caused by intrahepatic lithiasis (IHL) is crucial for timely and effective surgical intervention. The aim of the present study was to develop a nomogram to identify ICC associated with IHL (IHL-ICC).

METHODS

The study included 2,269 patients with IHL, who received pathological diagnosis after hepatectomy or diagnostic biopsy. Machine learning algorithms including Lasso regression and random forest were used to identify important features out of the available features. Univariate and multivariate logistic regression analyses were used to reconfirm the features and develop the nomogram. The nomogram was externally validated in two independent cohorts.

RESULTS

The seven potential predictors were revealed for IHL-ICC, including age, abdominal pain, vomiting, comprehensive radiological diagnosis, alkaline phosphatase (ALK), carcinoembryonic antigen (CEA), and cancer antigen (CA) 19-9. The optimal cutoff value was 2.05 µg/L for serum CEA and 133.65 U/mL for serum CA 19-9. The accuracy of the nomogram in predicting ICC was 82.6%. The area under the curve (AUC) of nomogram in training cohort was 0.867. The AUC for the validation set was 0.881 from The Second Affiliated Hospital of Wenzhou Medical University, and 0.938 from The First Affiliated Hospital of Fujian Medical University.

CONCLUSIONS

The nomogram holds promise as a novel and accurate tool to predict IHL-ICC, which can identify lesions in IHL in time for hepatectomy or avoid unnecessary surgical resection.

Plasma checkpoint protein 1 (Chk1) as a potential diagnostic biomarker for opisthorchiasis and cholangiocarcinoma

BACKGROUND

Patients infected with a parasite often develop opisthorchiasis viverrini, which often progresses into cholangiocarcinoma (CCA) due to the asymptomatic nature of the infection. Currently, there are no effective diagnostic methods for opisthorchiasis or cholangiocarcinoma.

OBJECTIVE

The aim of this study was to identify the host-responsive protein that can be developed as a diagnostic biomarker of opisthorchiasis and cholangiocarcinoma.

METHODS

Plasma samples were collected from non-OVCCA, OV, and CCA subjects, and the proteomes were investigated by LC-MS/MS. Venn diagrams and protein network prediction by STITCH were used to identify the potential biomarkers. The level of candidate protein, the plasma checkpoint protein 1 (Chk1), was measured by indirect enzyme-linked immunosorbent assay (ELISA).

RESULTS

Chk1 was present in the center of the protein network analysis in both the OV and CCA groups. In addition, the plasma Chk1 levels were significantly increased in both groups (P< 0.05). The sensitivity of the opisthorchiasis viverrini and cholangiocarcinoma was 59.38% and 65.62%, respectively, while the specificity of both was 85.71%.

CONCLUSION

Chk1 was identified by differential plasma proteomes and was increased in O. viverrini-infected and cholangiocarcinoma-derived plasma samples. Higher levels of plasma Chk1 levels may serve as a potential diagnostic biomarker for opisthorchiasis and cholangiocarcinoma.

Current management of intrahepatic cholangiocarcinoma: from resection to palliative treatments

Background

Intrahepatic cholangiocarcinoma (ICC) is the second most common liver primary tumour after hepatocellular carcinoma and represents 20% of all the cholangiocarcinomas. Its incidence is increasing and mortality rates are rising. Surgical resection is the only option to cure the disease, despite the high recurrence rates reported to be up to 80%. Intrahepatic recurrences may be still treated with curative intent in a small percentage of the patients. Unfortunately, due to lack of specific symptoms, most patients are diagnosed in a late stage of disease and often unsuitable for resection. Liver transplantation for ICC is still controversial. After the first published poor results, improving outcomes have been reported in highly selected cases, including locally advanced ICC treated with neoadjuvant chemotherapy, when successful in controlling tumour progression. Thus, liver transplantation should be considered a possible option within study protocols. When surgical management is not possible, palliative treatments include chemotherapy, radiotherapy and loco-regional treatments such as radiofrequency ablation, trans-arterial chemoembolization or radioembolization.

Conclusions

This update on the management of ICC focusses on surgical treatments. Known and potential prognostic factors are highlighted in order to assist in treatment selection.

Circulating TGF-β1 as the potential epithelial mesenchymal transition-biomarker for diagnosis of cholangiocarcinoma

Background

Cholangiocarcinoma (CCA) is a malignant tumor arising from bile duct epithelium. The oncogenic risk factor is infection by the liver fluke, Opisthorchis viverrini (Ov). One of key mechanism in the development of CCA is epithelial mesenchymal transition (EMT). We aimed to investigate the expression of EMT-related proteins namely, E-cadherin, TGF-β1 and BMP-7 in CCA tissues, to determine the level of candidate EMT-related protein, and to examine whether there were significant correlations with clinicopathological data in sera of CCA patients compared with normal groups.

Methods

The expression of E-cadherin, TGF-β1 and BMP-7 was analyzed in human CCA tissues by immunohistochemistry and altered expressions compared to clinicopathological data were analyzed to identify the potential candidate EMT-biomarker. Subsequently, the level of candidate marker was determined in sera of CCA patients compared with normal and inflammatory-related diseases groups by enzyme-linked immunosorbent assay (ELISA).

Results

Immunohistochemical analysis showed that E-cadherin was expressed at a low level whereas TGF-β1 and BMP-7 showed high expression in CCA tissues when compared with liver from cadaveric donor. Interestingly, only high TGF-β1 expression in CCA tissues was significantly correlated with lymph node metastasis, severe cancer stage, intrahepatic CCA type and shorter survival time of CCA patients (P<0.05). Consequently, TGF-β1 was selected to determine the level in serum of CCA patients using ELISA. The results showed that serum TGF-β1 level was elevated in CCA patients compared to the normal group. Patients with high TGF-β1 levels were significantly correlated with metastasis status (P=0.03). Furthermore, receiver operating characteristic (ROC) analysis showed that serum TGF-β1 level is effective in distinguishing CCA patients from normal at the cut-off of 38.54 ng/mL with high sensitivity (71.1%) and specificity (68.9%) and from inflammatory-related diseases group at the cut-off of 38.67 ng/mL with effective sensitivity (68.0%) and specificity (71.1%). Furthermore, TGF-β1 could serve as a novel metastatic biomarker in CCA to diagnose the disease with 48.95 ng/mL as the cut-off along with the desired sensitivity and specificity (48.2% and 88.9% respectively).

Conclusions

The results of this study show that TGF-β1 could be a potential EMT-biomarker for diagnosis and prognosis of CCA.

Management Strategies for Patients with Hilar Cholangiocarcinomas: Challenges and Solutions

Advances in imaging, pathology and therapy have resulted in major improvements in the management of cholangiocarcinomas; the mortality has come down and with it there has been an improved 5-year survival. Surgical resection remains the treatment of choice and reports from high volume centres have shown an increase in resectability rates, R0 resection, a decrease in mortality and an improvement in 5-year survival; however, the operative morbidity remains high, pointing towards the complexity of the management of these difficult lesions. Complete excision is also often limited by the locally advanced nature of the disease at the time of diagnosis and a proportion of patients who were earlier deemed resectable on imaging are found to have unresectable disease at the time of operation. Neoadjuvant therapy has had only a limited impact on survival. Liver transplantation is also an option in a few patients following strict criteria for selection. Since the large majority of patients are only diagnosed at the late stages of the disease palliation (endoscopic or surgical) is an important part of treatment. Portal vein embolisation and pre-operative biliary drainage have had a major impact on outcomes. Major liver resection with caudate lobe removal remains the standard operation and procedures like routine vascular resection and liver transplant should only be carried out in experienced centres. Improvements in both neo as well as adjuvant therapy may lead to a standardized protocol in the future, as well as an improvement in survival.

Systematic literature review of IL-6 as a biomarker or treatment target in patients with gastric, bile duct, pancreatic and colorectal cancer

Gastrointestinal cancer (GI) is a major health problem. Patients with gastric, pancreatic, colorectal, bile duct and gall bladder cancer often have advanced disease at the time of diagnosis and are generally difficult to cure, resulting in a dismal prognosis for most patients. Inflammation plays an important role in the development and growth of cancer, which has led to a growing interest in the pro-inflammatory cytokine interleukin 6 (IL-6). The aim of the present review was to evaluate the clinical use of IL-6 as a biomarker or therapeutic target in patients with GI cancer. We did a systematic review of studies (1993-2018), to assess the clinical use of IL-6 as a diagnostic, prognostic or predictive tumor biomarker or as a potential therapeutic target. This review includes 48 studies and 5316 patients. Circulating IL-6 levels appear to be an independent prognostic biomarker in patients with GI cancer, with high IL-6 levels associated with short overall survival (OS). The results for colorectal cancer were too ambiguous to give conclusive results. IL-6 seemed to be a marker for some of the clinical characteristics of GI cancer, and may have a role in the diagnostic workup in general practice. No published studies have examined the use of IL-6 as a therapeutic target in pancreatic, gastric, bile duct or colorectal cancer. In conclusion, high circulating IL-6 was associated with short OS in most studies in GI cancer patients. Whether inhibition of IL-6 would decrease GI cancer symptoms and increase quality of life is unknown.

Ultrasound surveillance for cholangiocarcinoma in an endemic area: A prove of survival benefits

BACKGROUND AND AIM

Cholangiocarcinoma (CCA) is an aggressive malignancy with rapid progression and poor prognosis. Abdominal ultrasound surveillance may detect early-stage malignancy and improve surgical outcome. However, little data exist on the benefits of abdominal ultrasound surveillance in populations at high risk for CCA development in an endemic area. This study compared survival outcomes of CCA patients recruited through abdominal ultrasound surveillance program and those presented to the hospital independent of surveillance.

METHODS

The surveillance population-based cohort was 4225 villagers in Northern Thailand, aged 30-60 years, who consented to a 5-year abdominal ultrasound surveillance program, which included interval ultrasound examinations every 6 months. The non-surveillance cohort was hospital-based CCA patients diagnosed during April 2007 to November 2015. Numbers of operable tumors, percentages of R0 resection, and survival analyses were compared between the two cohorts.

RESULTS

There were 48 and 192 CCA patients in the surveillance and the non-surveillance cohorts, respectively. Of these, 37/48 (77.1%) and 22/192 (11.5%) were in an operable stage and R0 resections performed in 36/48 (97.3%) and 14/192 (63.6%), respectively. The median survival in each group was 31.8 and 6.7 months, respectively (with correction of lead time bias) (P < 0.0001). By multivariate analysis, abdominal ultrasound surveillance (hazard ratio [HR] = 0.41; P = 0.012), operable stage (HR = 0.11; P < 0.001), and serum albumin ≥ 3.5 g/dL (HR = 0.42; P < 0.001) were significantly associated with decreased mortality, whereas size of CCA (HR = 1.11; P < 0.001), serum alanine aminotransferase > 40 IU/L (HR = 1.71; P = 0.017), and tumor recurrence (HR = 4.86; P = 0.017) were associated with increased mortality.

CONCLUSION

Abdominal ultrasound surveillance provided survival benefits and should be considered in areas highly endemic for CCA to reduce mortality.

A novel nomogram for the prediction of intrahepatic cholangiocarcinoma in patients with intrahepatic lithiasis complicated by imagiologically diagnosed mass

Background

Accurate preoperative diagnosis of intrahepatic cholangiocarcinoma (ICC) among patients with imagiologically intrahepatic lithiasis (IHL) complicated by mass is crucial for timely and effective surgical intervention. The aim of the present study was to develop a nomogram to identify ICC associated with IHL (IHL-ICC).

Patients and methods

Data were obtained from a total of 252 consecutive patients with IHL complicated by mass. Multivariate logistic regression analysis was conducted to identify the clinicopathologic and imagiological characteristics that were potentially associated with ICC. A nomogram was developed based on the results of the multivariate analysis, and the value for prediction of ICC was assessed.

Results

The study revealed six potential predictors for IHL-ICC, including comprehensive imagiological diagnosis, biliary tract operation history, fever, ascites, cancer antigen (CA) 19-9, and carcinoembryonic antigen (CEA). The optimal cutoff value was 3.75 μg/L for serum CEA and 143.15 U/mL for serum CA 19-9. The accuracy of the nomogram in predicting ICC was 78.5%. The Youden index provided a value of 0.348, corresponding to a cutoff of 95 points, with an area under the curve of 0.863.

Conclusion

The nomogram holds promise as a novel and accurate tool in identifying IHL-ICC for hepatectomy, and in the differentiation of benign occupying lesions in IHL patients, resulting in the avoidance of unnecessary surgical resection.

Biomarkers for the Diagnosis of Cholangiocarcinoma: A Systematic Review

Cholangiocarcinoma (CCA), a malignant tumor of the bile duct, is a major public health problem in many Southeast Asian countries, particularly Thailand. The slow progression makes it difficult for early diagnosis and most patients are detected in advanced stages. This study aimed to review all relevant articles related to the biomarkers for the diagnosis of CCA and point out potential biomarkers. A thorough search was performed in PubMed and ScienceDirect for CCA biomarker articles. Required data were extracted. A total of 46 articles that fulfilled the inclusion and had none of the exclusion criteria were included in the analysis (17, 22, 3, 4, and 1 articles on blood, tissue, bile, both blood and tissue, and urine biomarkers, respectively). Carbohydrate antigen 19-9 (CA19-9) and carcinoembryonic antigen (CEA), either alone or in combination with other biomarkers, are the most commonly studied biomarkers in the serum. Their sensitivity and specificity ranged from 47.2% to 98.2% and 89.7% to 100%, respectively. However, in the tissue, gene methylations and DNA-related markers were the most studied CCA biomarkers. Their sensitivity and specificity ranged from 58% to 87% and 98% to 100%, respectively. Some articles investigated biomarkers both in blood and tissues, particularly CA19-9 and CEA, with sensitivity and specificity ranging from 33% to 100% and 50% to 97.7%, respectively. Although quite a number of biomarkers with a potential role in the early detection of CCA have been established, it is difficult to single out any particular marker that could be used in the routine clinical settings.

Opisthorchiasis and cholangiocarcinoma in Southeast Asia: an unresolved problem

The prevalence of cholangiocarcinoma (CCA) in Southeast Asia is much higher than other areas of the world. Eating raw, fermented, or undercooked cyprinid fish, infected with the liver fluke, Opisthorchis viverrini sensu lato (sl), results in chronic biliary inflammation, periductal fibrosis, and increased cancer risk. There may be associated glomerulonephritis. The process of infection is difficult to disrupt because eating practices have proven extremely difficult to change, and the life cycle of the fluke cannot be broken due to high prevalence in canine and feline reservoir hosts. Fecal analysis and enzyme-linked immunosorbent assay tests can be used to diagnose opisthorchiasis. Diagnosis of CCA is complex, partly due to the lack of definitive imaging characteristics but also due to the difficulty of obtaining samples for cytology or histology. This cancer has proven to be resistant to common chemotherapy treatments and so the two avenues of treatment available are surgical resection and liver transplantation, both requiring early detection of the tumor for the best chances of success. Late presentation of symptoms reduces the chances of successful surgical intervention. While liver fluke infections can be treated with praziquantel, individuals will often become reinfected, and multiple reinfections can be more harmful than a singular, long-term infection. A key research on the detection and characterization of novel biomarkers in all parts of the carcinogenic pathway for early diagnosis is needed.

Monitoring outcomes in intrahepatic cholangiocarcinoma patients following hepatic resection

Intrahepatic cholangiocarcinoma (iCCA) is one of the fatal gastrointestinal cancers with increasing incidence and mortality. Although surgery offers the only potential for cure in iCCA patients, the prognosis is not optimal with low overall survival rate and high disease recurrence. Hence, adjuvant therapy is generally recommended in the management of high-risk patients. Identifying factors associated with disease recurrence and survival of the iCCA patients after resection will improve understanding of disease prognosis and help in selecting patients who will benefit from surgical resection or stratifying them for clinical trials. Despite development of new methods for early detection of tumor recurrence, effective prognostic models and nomograms, and recent advances in management, significant challenges remain in improving the prognosis of iCCA patients.

Serum microRNAs as novel biomarkers for primary sclerosing cholangitis and cholangiocarcinoma

The diagnosis of primary sclerosing cholangitis (PSC) is difficult due to the lack of sensitive and specific biomarkers, as is the early diagnosis of cholangiocarcinoma (CC), a complication of PSC. The aim of this study was to identify specific serum miRNAs as diagnostic biomarkers for PSC and CC. The levels of 667 miRNAs were evaluated in 90 human serum samples (30 PSC, 30 CC and 30 control subjects) to identify disease-associated candidate miRNAs (discovery phase). The deregulated miRNAs were validated in an independent cohort of 140 samples [40 PSC, 40 CC, 20 primary biliary cirrhosis (PBC) and 40 controls]. Receiver operating characteristic (ROC) curves were established and only miRNAs with an area under the curve (AUC) > 0·70 were considered useful as biomarkers. In the discovery phase we identified the following: 21 miRNAs expressed differentially in PSC, 33 in CC and 26 in both in comparison to control subjects as well as 24 miRNAs expressed differentially between PSC and CC. After the validation phase, miR-200c was found to be expressed differentially in PSC versus controls, whereas miR-483-5p and miR-194 showed deregulated expression in CC compared with controls. We also demonstrate a difference in the expression of miR-222 and miR-483-5p in CC versus PSC. Combination of these specific miRNAs further improved the specificity and accuracy of diagnosis. This study provides a basis for the use of miRNAs as biomarkers for the diagnosis of PSC and CC.

Expert consensus document: Cholangiocarcinoma: current knowledge and future perspectives consensus statement from the European Network for the Study of Cholangiocarcinoma (ENS-CCA)

Cholangiocarcinoma (CCA) is a heterogeneous group of malignancies with features of biliary tract differentiation. CCA is the second most common primary liver tumour and the incidence is increasing worldwide. CCA has high mortality owing to its aggressiveness, late diagnosis and refractory nature. In May 2015, the "European Network for the Study of Cholangiocarcinoma" (ENS-CCA: www.enscca.org or www.cholangiocarcinoma.eu) was created to promote and boost international research collaboration on the study of CCA at basic, translational and clinical level. In this Consensus Statement, we aim to provide valuable information on classifications, pathological features, risk factors, cells of origin, genetic and epigenetic modifications and current therapies available for this cancer. Moreover, future directions on basic and clinical investigations and plans for the ENS-CCA are highlighted.

Levels of soluble LR11/SorLA are highly increased in the bile of patients with biliary tract and pancreatic cancers

BACKGROUND

The utility of molecules derived from cancer cells as biomarkers of the pathological status in biliary tract and pancreatic cancers is still limited. Soluble LDL receptor relative with 11 ligand-binding repeats (sLR11), a molecule released from immature cells, has been shown to be a circulating biomarker for early stage hematological malignancies.

METHODS

We have evaluated the pathological significance of bile sLR11 levels in 147 samples from 72 patients with biliary tract cancer (BTC), pancreatic cancer (PC), or benign diseases.

RESULTS

The bile sLR11 levels in the cancer patients were significantly increased compared with those in patients without cancer, independent of cytological detection of cancer cells in bile. The average bile sLR11 levels in cancer patients were significantly higher than in those with benign diseases, while levels of bile carbohydrate antigen 19-9 (CA19-9) and carcinoembryonic antigen (CEA) were not different. LR11 protein was found to be highly expressed in the BTC and PC cells. The LR11 transcript levels in cholangiocarcinoma and pancreatic cancer cell lines were sharply induced during proliferation and significantly increased under hypoxic conditions.

CONCLUSIONS

Therefore, sLR11 levels in bile may be indicative of cancer cell conditions and may serve as potential novel biomarker in patients with BTC and PC.

The Role of Biliary Carcinoembryonic Antigen-Related Cellular Adhesion Molecule 6 (CEACAM6) as a Biomarker in Cholangiocarcinoma

Objective

The aim of the present study is to determine if CEACAM6 can be detected in the bile of patients with biliary cancer and can serve as a diagnostic biomarker for cholangiocarcinoma.

Summary Background Data

Distinguishing bile duct carcinoma from other diagnoses is often difficult using endoscopic or percutaneous techniques. The cell surface protein CEACAM6 is over-expressed in many gastrointestinal cancers and may be selectively elevated in biliary adenocarcinoma.

Methods

Bile from patients with benign biliary disease and cholangiocarcinoma (hilar, intrahepatic and distal) was collected at the time of index operation. The concentration of CEACAM6 was quantified by sandwich enzyme-linked immunosorbent assay (ELISA) and correlated to pathologic diagnosis. Diagnostic capability of CEACAM6 was evaluated by Wilcoxon rank-sum, linear regression, multiple regression, and receiver operating characteristic (ROC) curve analysis.

Results

Bile from 83 patients was analyzed: 42 with benign disease and 41 with cholangiocarcinoma. Patients in the benign cohort were younger, predominantly female, and had lower median biliary CEACAM6 levels than patients in the malignant cohort (7.5 ng/ml vs. 40 ng/ml; p = <.001). ROC curve analysis determined CEACAM6 to be a positive predictor cholangiocarcinoma with a CEACAM6 level >14 ng/ml associated with 87.5% sensitivity, 69.1% specificity, and a likelihood ratio of 2.8 (AUC 0.74). Multiple regression analysis suggested elevated alkaline phosphatase and the presence of biliary endoprostheses may influence CEACAM6 levels.

Conclusion

Biliary CEACAM6 can identify patients with extrahepatic cholangiocarcinoma with a high degree of sensitivity and should be investigated further as a potential screening tool.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

How Should Cancer Surveillance in Primary Sclerosing Cholangitis Be Performed?

Background

Primary sclerosing cholangitis (PSC) is a chronic inflammatory disease affecting the intra- and extrahepatic bile duct system that can ultimately cause liver cirrhosis. Apart from the risk of progression to end-stage liver disease the prognosis of PSC is primarily determined by the risk to develop hepatobiliary or extrahepatic malignancies. A reasonable surveillance strategy for PSC patients must allow the detection of early cancer that will permit a potentially curative therapy.

Methods

Current guidelines on malignancy within the context of PSC as well as the primary literature were reviewed for this article.

Results

Here, we focus on a concise review of the three tumors most commonly associated with PSC: cholangiocellular carcinoma (CCA), gallbladder cancer, and colorectal carcinoma. For cancer surveillance in this patient group, endoscopy, cholangiography, cross-sectional imaging, and the use of serum tumor markers are principally available. Furthermore, for the diagnosis of CCA novel approaches were recently suggested to improve sensitivity and specificity to detect this malignancy.

Conclusion

We review different aspects of cancer surveillance in patients with PSC. Since prospective data on the surveillance of malignant tumors is unavailable, we discuss a rational approach on how to perform cancer surveillance in patients with PSC.

Serum CYFRA 21-1 in Biliary Tract Cancers: A Reliable Biomarker for Gallbladder Carcinoma and Intrahepatic Cholangiocarcinoma

BACKGROUND

Biliary tract cancers encompass gallbladder carcinoma, and intrahepatic, perihilar and distal cholangiocarcinoma. Upregulated serum CYFRA 21-1 has been reported in intrahepatic cholangiocarcinoma.

AIMS

The present study aimed to explore the clinical significance of serum CYFRA 21-1 in all biliary tract cancer subtypes.

METHODS

Serum CYFRA 21-1, carbohydrate antigen 19-9 and carcinoembryonic antigen were quantitated preoperatively, postoperatively and during follow-up in 134 malignant and 52 benign patients. Receiver operator characteristic curves of biomarkers were analyzed. Level of CYFRA 21-1 was correlated with patients' clinicopathological features and follow-up data.

RESULTS

CYFRA 21-1 was significantly upregulated in biliary malignancies, and expressional difference existed between these subtypes. Based on the maximal Youden's index, cutoff values were selected (ng/mL): 2.61 for biliary tract cancers (sensitivity 74.6 % and specificity 84.6 %); 3.27 for intrahepatic cholangiocarcinoma (75.6 and 96.2 %) and gallbladder carcinoma (93.7 and 96.2 %); 2.27 for perihilar cholangiocarcinoma (71.0 and 71.2 %); and 2.61 for distal cholangiocarcinoma (63.3 and 84.6 %). CYFRA 21-1 showed better diagnostic performance than other biomarkers in gallbladder carcinoma and intrahepatic cholangiocarcinoma; its performance was not inferior to that of the combination of these three biomarkers and declined after curative resection and re-elevated when tumor recurred, which was correlated with tumor aggressiveness and TNM stage; it was an independent predictor for 1-year recurrence-free survival and overall survival on multivariate analysis.

CONCLUSION

Serum CYFRA 21-1 represents a reliable biomarker for gallbladder carcinoma and intrahepatic cholangiocarcinoma.

Bile proteome in health and disease

The study of bile proteins could improve the understanding of physiological processes involved in the regulation of the hepato-biliary system. Researchers have tried for years to investigate the bile proteome but, until recently, only a few tens of proteins were known. The advent of proteomics, availing of large-scale analytical devices paired with potent bioinformatic resources, lately allowed the identification of thousands of proteins in bile. Nevertheless, the knowledge of their role in the hepato-biliary system still represents almost a "blank page in the book of physiology." In this review, we first guide the reader through the historical phases of the analysis of bile protein content, emphasizing the recent progresses achieved through the use of proteomic techniques. Thereafter, we deeply explore the involvement of bile proteins in health and disease, with a particular focus on the discovery of biomarkers for biliary tract malignancies.

Preoperative high level of D-dimers predicts unresectability of pancreatic head cancer

AIM: To assess the value of D-dimer level in determining resectability of pancreatic cancer.

METHODS: Preoperative prediction of pancreatic head cancer resectability remains inaccurate. The use of hemostatic factors may be of potential help, since D-dimers correlate with tumor stage. Single center clinical trial study comprised patients with potentially resectable pancreatic head tumor and without detectable venous thrombosis (n = 64). Resectability was defined as no evidence of nodal involvement, distant spread and no invasion of mesenteric vessels. Final decision of resectability was confirmed intraoperatively. Experienced pancreatic surgeon performed all surgeries. Following the dissection of hepatoduodenal ligament, samples of portal blood and bile were taken. Peripheral blood via central line and urine via Foley catheter were sampled. D-dimer levels were further measured.

RESULTS: At laparotomy only 29 (45.3%) tumors were found to be resectable. Our analysis showed higher by 57.5% (P < 0.001) mean D-dimer values in peripheral and 43.7% (P = 0.035) in portal blood of patients with unresectable pancreatic cancer. Significant differences were not observed when analyzing D-dimer levels in bile and urine. Peripheral D-dimer level correlated with pancreatic cancer resectability. When cut-off D-dimer value of 570.6 μg/L was used, the sensitivity for assessment of tumor unresectability was 82.8%. Furthermore, D-dimer level in peripheral blood of metastatic disease (n = 15) was significantly higher when compared to locally advanced (n = 20) pancreatic cancer (2470 vs 1168, P = 0.029). The area under ROC curve for this subgroup of patients was 0.87; for determination of unresectable disease when threshold of 769.8 μg/L was used, sensitivity and specificity was 86.6% and 80%, respectively.

CONCLUSION: Patients with resectable pancreatic head cancer based on preoperative imaging studies and high D-dimer level may be considered unresectable due to occult hepatic metastases. These patients may benefit from diagnostic laparoscopy to avoid exploratory laparotomy.

Angiopoietin-2 and biliary diseases: elevated serum, but not bile levels are associated with cholangiocarcinoma

Background

The diagnosis of cholangiocarcinoma (CC) is challenging especially in patients with primary sclerosing cholangitis (PSC) and often delayed due to the lack of reliable markers. Angiopoietin-2 (Angpt-2) has been employed as a biomarker of angiogenesis and might be involved in tumor neoangiogenesis.

Aim

To evaluate the diagnostic potential of Angpt-2 as a biomarker to detect patients with CC.

Methods

Bile and serum Angpt-2 levels were measured in patients with CC (n = 45), PSC (n = 74), CC complicating PSC (CC/PSC) (n = 11) and patients with bile duct stones (n = 37) in a cross sectional study. Diagnostic accuracy of Angpt-2 was compared to carbohydrate antigen 19-9 (CA19-9). Fluorescent immunohistochemistry from human CC liver tissue samples was performed to localize the origin of Angpt-2.

Results

Serum Angpt-2 concentration was significantly elevated in patients with CC compared to control patients (p<0.05). Diagnostic accuracy of Angpt-2 as determined by receiver operating characteristic (ROC) analysis resulted in a higher area under the curve (AUC) value compared to CA19-9 (AUC: 0.85 versus 0.77; 95% confidence interval (CI): 0.74–0.93 versus 0.65–0.87, respectively). Angpt-2 was also detectable in bile, but was not associated with the presence of CC. Immunohistochemistry revealed a strong induction of Angpt-2 expression in the tumor vasculature.

Conclusions

Circulating Angpt-2 in serum might be a promising protein candidate locally derived from the tumor vasculature in patients with CC. Measurement of Angpt-2 in serum may be useful for diagnosis and further clinical management of patients with CC.

Cholangiocarcinoma: Biology, Clinical Management, and Pharmacological Perspectives

Cholangiocarcinoma (CCA), or tumor of the biliary tree, is a rare and heterogeneous group of malignancies associated with a very poor prognosis. Depending on their localization along the biliary tree, CCAs are classified as intrahepatic, perihilar, and distal, and these subtypes are now considered different entities that differ in tumor biology, the staging system, management, and prognosis. When diagnosed, an evaluation by a multidisciplinary team is essential; the team must decide on the best therapeutic option. Surgical resection of tumors with negative margins is the best option for all subtypes of CCA, although this is only achieved in less than 50% of cases. Five-year survival rates have increased in the recent past owing to improvements in imaging techniques, which permits resectability to be predicted more accurately, and in surgery. Chemotherapy and radiotherapy are relatively ineffective in treating nonoperable tumors and the resistance of CCA to these therapies is a major problem. Although the combination of gemcitabine plus platinum derivatives is the pharmacological treatment most widely used, to date there is no standard chemotherapy, and new combinations with targeted drugs are currently being tested in ongoing clinical trials. This review summarizes the biology, clinical management, and pharmacological perspectives of these complex tumors.

Cancer biomarker discovery for cholangiocarcinoma: the high-throughput approaches

Cholangiocarcinoma (CCA) is difficult to diagnose at an early stage and most tumors are detected at late stage where surgery or other therapy is ineffective. Many advanced techniques are applied to diagnose CCA; however, most are expensive and have varying degrees of accuracy. A less invasive and simpler procedure such as serum markers would be of substantial clinical benefit for diagnosis, monitoring, and predicting outcome for CCA patients. Recent advances in "Omics" technologies offer remarkable opportunities for establishment of biomarker-related to diseases. In this review, the potential biomarkers obtained from proteomics and glycomic studies are evaluated. Several protein markers were discovered from patient specimen, using two dimensional-differential gel electrophoresis couple with liquid chromatography tandem mass spectrometry (2D-DIGE/LC-MS-MS), matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF-MS), surface enhanced laser desorption/ionization (SELDI)-TOF-MS and capillary electrophoresis (CE)-MS, etc. Newly reported CCA-associated glyco-biomarkers were identified using lectin-assisted, monoclonal antibody-assisted or specific-target strategies. The combination between carbohydrate binding-lectin and core protein-binding mAb significantly increased the values for detection of the glyco-biomarkers for CCA. Searching for specific and sensitive molecular markers to be used for population screening is worth being evaluated. This could lead to earlier diagnosis and improve outcome. Further investigation of those biomarker functions is also of value in order to better understand the tumor biology and use them as targets for future therapeutic agents.

Increase of exostosin 1 in plasma as a potential biomarker for opisthorchiasis-associated cholangiocarcinoma

A proteomic-based approach was used to search for potential markers in the plasma of hamsters in which cholangiocarcinoma (CCA) was induced by Opisthorchis viverrini infection and N-nitrosodimethylamine treatment. The plasma proteins of CCA-induced hamsters were resolved by 1-D PAGE, digested by trypsin, and analyzed by LC-MS/MS. From the criteria of protein ID scores >15 and an overexpression of at least three times across all time points, 37 proteins were selected. These overexpressed proteins largely consisted of signal transduction, structural, transport, and transcriptional proteins in the order. Among the most frequently upregulated proteins, exostosin 1 (EXT1) was selected for further validation. By western blot analysis, the EXT1 expression level in the plasma of hamster CCA was significantly higher than that of controls at 1 month and thereafter. Immunohistochemistry revealed that EXT1 was expressed at vascular walls and fibroblasts at 21 days (before tumor onset) and at 2 months (early CCA) posttreatment. Its expression was also observed in bile duct cancer cells during tumor progression at 6 months posttreatment. In the human CCA tissue microarray, EXT1 immunoreactivity was found not only in vascular walls and fibroblasts but also in bile duct cancer cells and was positive in 89.7 % (61/68) of the cases. By ELISA and immunoblotting, plasma EXT1 level was significantly higher in human CCA compared to healthy controls. In conclusion, these results suggest that increased expression of EXT1 level in the plasma might be involved in CCA genesis and might be a potential biomarker of CCA.

Increased TERC gene copy number and cells in senescence in primary sclerosing cholangitis compared to colitis and control patients

OBJECTIVE

Primary sclerosing cholangitis (PSC) is a chronic cholestatic disorder that involves inflammatory and fibrotic changes in the bile ducts. Up to 80% of patients have concomitant inflammatory bowel disease (IBD) with colitis. PSC patients are predisposed to develop hepatobiliary, colonic and other extrahepatic malignancies, probably related to inflammatory processes that might promote carcinogenesis. Telomerase is an enzyme complex that lengthens telomeres and has enhanced expression in numerous malignancies. In this study, we evaluated the TERC gene copy number, the proportion of cells in senescence and the amount of fragmentation in the senescent state.

METHODS

Fluorescence in situ hybridization (FISH) for the TERC gene was applied to lymphocytes retrieved from PSC (N=19), colitis (N=20) and healthy control patients (N=20) to determine the TERC copy number. On the same FISH slides, cells stained with DAPI were also analyzed for senescence-associated heterochromatin foci (SAHF) status, including the number of cells with fragments and the number of SAHF fragments in each cell.

RESULTS

A higher TERC gene copy number was observed in cells from PSC patients compared to colitis and control group patients. It was also higher in the colitis than in the control group. Significantly more cells in the senescent state and more fragmentation in each cell were observed in the PSC group compared to colitis and control groups.

CONCLUSION

The TERC gene copy number and the number of cells in the senescent state were increased in PSC patients compared to the colitis and control groups. These findings are probably related to the genetic instability parameters that reflect the higher tendency of this patient group to develop malignancies.

Primary sclerosing cholangitis and cholangiocarcinoma: pathogenesis and modes of diagnostics

Primary sclerosing cholangitis (PSC) is a chronic cholestatic liver disease caused by progressive inflammation of the intra- and extrahepatic bile duct system. PSC patients have an increased risk to develop hepatobiliary as well as extrahepatic malignancies. The goal of a surveillance strategy for hepatobiliary malignancy in these patients is the detection of early cancer which will allow a potentially curative therapy. Here, we focus on a conceptual review of the pathogenesis of cholangiocellular carcinoma and gallbladder cancer and we will discuss a rational approach for the surveillance of these malignancies in PSC patients.

The tumorigenic liver fluke Opisthorchis viverrini--multiple pathways to cancer

Liver fluke infection caused by Opisthorchis viverrini is a major public health problem in Thailand and adjacent countries. In addition to infection-associated morbidity, infection with O. viverrini and the related Clonorchis sinensis are unarguable risk factors for cholangiocarcinoma (CAA, bile-duct cancer). Here we review the pathogenesis of opisthorchiasis and the association between O. viverrini infection and bile-duct cancer, focusing on the molecular parallels between wound healing, chronic inflammation, and cancer development. We review a schema for human disease progression from fluke infection, chronic opisthorchiasis, advanced periductal fibrosis, and cholangiocarcinogenesis, and present a rationale for biomarker discovery to facilitate early intervention. We conclude by addressing post-genomic advances with a view to developing new control strategies to combat this infectious cancer.

Primary sclerosing cholangitis and malignancy

Cholangiocarcinoma complicates primary sclerosing cholangitis (PSC) in approximately 10% of cases, but no risk factor that can identify this subgroup of patients is known. No imaging modalities or serum tumour markers that can diagnose early cholangiocarcinoma are available, but endoscopic retrograde cholangiography with brush cytology is recommended when clinically indicated. Liver transplantation with neoadjuvant therapy is carried out in specialist centres in cases of limited stage cancer. Transplantation should also be considered in patients with biliary dysplasia without evident tumour. Gallbladder polyps in PSC are often malignant, and liberal indication for cholecystectomy is recommended. Hepatocellular carcinoma develops in 2%-4% of patients with end-stage liver disease. Patients with inflammatory bowel disease are at risk of colorectal neoplasia. Surveillance colonoscopies are recommended, also after liver transplantation. Epigenetic markers represent one among several classes of potential biomarkers for early diagnosis of malignancies in PSC that should be further explored.

Elevated levels of neutrophil gelatinase-associated lipocalin in bile from patients with malignant pancreatobiliary disease

OBJECTIVES

Accurate differentiation between benign and malignant causes of biliary obstruction remains challenging and reliable biomarkers are urgently needed. Bile is a potential source of such biomarkers. Our aim was to apply a proteomic approach to identify a potential biomarker in bile that differentiates between malignant and benign disease, and to assess its diagnostic accuracy. Neutrophil gelatinase-associated lipocalin (NGAL) is multi-functional protein, released from activated neutrophils, with roles in inflammation, immune function, and carcinogenesis. It has not previously been described in bile.

METHODS

Bile, urine, and serum were collected prospectively from 38 patients undergoing endoscopic retrograde cholangiopancreatography ("discovery" cohort); 22 had benign and 16 had malignant pancreatobiliary disease. Initially, label-free proteomics and immunoblotting were performed in samples from a subset of these patients. Enzyme-linked immunosorbent assay was then performed for NGAL as a potential biomarker on all samples in this cohort. The diagnostic performance of biliary NGAL was then validated in a second, independent group ("validation" cohort) of 21 patients with pancreatobiliary disease (benign n=14, malignant n=7).

RESULTS

NGAL levels were significantly raised in bile from the malignant disease group, compared with bile from the benign disease group in the discovery cohort (median 1,556 vs. 480 ng/ml, P=0.007). Biliary NGAL levels had a receiver operating characteristic area under curve of 0.76, sensitivity 94%, specificity 55%, positive predictive value 60%, and negative predictive value 92% for distinguishing malignant from benign causes. Biliary NGAL was independent of serum biochemistry and carbohydrate antigen 19-9 (CA 19-9) in differentiating between underlying benign and malignant disease. No significant differences in serum and urine NGAL levels were found between benign and malignant disease. Combining biliary NGAL and serum CA 19-9 improved diagnostic accuracy for malignancy (sensitivity 85%, specificity 82%, positive predictive value 79%, and negative predictive value 87%). The diagnostic accuracy of biliary NGAL was confirmed in the second independent validation cohort.

CONCLUSIONS

NGAL in bile is a novel potential biomarker to help distinguish benign from malignant biliary obstruction.

Markers of bile duct tumors

Biliary tract carcinomas are relatively rare, representing less than 1% of cancers. However, their incidence has increased in Japan and in industrialized countries like the USA. Biliary tract tumors have a poor prognosis and a high mortality rate because they are usually detected late in the course of the disease; therapeutic treatment options are often limited and of minimal utility. Recent studies have shown the importance of serum and molecular markers in the diagnosis and follow up of biliary tract tumors. This review aims to introduce the main features of the most important serum and molecular markers of biliary tree tumors. Some considerable tumor markers are cancer antigen 125, carbohydrate antigen 19-9, carcinoembryonic antigen, chromogranin A, mucin 1, mucin 5, alpha-fetoprotein, claudins and cytokeratins.

Bile proteomic profiles differentiate cholangiocarcinoma from primary sclerosing cholangitis and choledocholithiasis

Early detection of malignant biliary tract diseases, especially cholangiocarcinoma (CC) in patients with primary sclerosing cholangitis (PSC), is very difficult and often comes too late to give the patient a therapeutic benefit. We hypothesize that bile proteomic analysis distinguishes CC from nonmalignant lesions. We used capillary electrophoresis mass spectrometry (CE-MS) to identify disease-specific peptide patterns in patients with choledocholithiasis (n = 16), PSC (n = 18), and CC (n = 16) in a training set. A model for differentiation of choledocholithiasis from PSC and CC (PSC/CC model) and another model distinguishing CC from PSC (CC model) were subsequently validated in independent cohorts (choledocholithiasis [n = 14], PSC [n = 18] and CC [n = 25]). Peptides were characterized by sequencing. Application of the PSC/CC model in the independent test cohort resulted in correct exclusion of 12/14 bile samples from patients with choledocholithiasis and identification of 40/43 patients with PSC or CC (86% specificity, 93% sensitivity). The corresponding receiver operating characteristic (ROC) analysis revealed an area under the curve (AUC) of 0.93 (95% confidence interval [CI]: 0.82-0.98, P = 0.0001). The CC model succeeded in an accurate detection of 14/18 bile samples from patients with PSC and 21/25 samples with CC (78% specificity, 84% sensitivity) in the independent cohort, resulting in an AUC value of 0.87 (95% CI: 0.73-0.95, P = 0.0001) in ROC analysis. Eight out of 10 samples of patients with CC complicating PSC were identified.

CONCLUSION

Bile proteomic analysis discriminates benign conditions from CC accurately. This method may become a diagnostic tool in future as it offers a new possibility to diagnose malignant bile duct disease and thus enables efficient therapy particularly in patients with PSC.

Hepatocellular carcinoma expressing cholangiocyte phenotype is a novel subtype with highly aggressive behavior

BACKGROUND

The pathobiological features and surgical outcomes of patients with classical hepatocellular carcinoma (HCC)-expressing cholangiocyte markers that we named dual-phenotype HCC (DPHCC) remain unclear. The purpose of this study was to assess the association between the phenotype and surgicopathologic features of DPHCC.

METHODS

A retrospective single-center study was performed on the surgicopathologic features of DPHCC from 1530 consecutive surgical specimens. Immunohistochemical staining was performed with antibodies to hepatocytes (Hep Par 1/pCEA) and cholangiocytes (cytokeratin 19 [CK19]/mucin core protein-1 [MUC-1]).

RESULTS

DPHCC accounted for 10.1% (n = 155) of total HCCs. The serum alfa-fetoprotein and CA19-9 were elevated in 87.7% (n = 136) and 20.7% (n = 32) of patients, respectively; the former had close correlation with the immunostaining of CK19 (P < 0.01). The combination of immunostaining intensities of CK19 and MUC-1 was significantly associated with tumor size, microvascular invasion, and satellite nodule formation (P < 0.05-0.01). Compared to patients with pure HCC, those with DPHCC had significantly lower overall survival (30.4 ± 3.7 vs. 43.6 ± 3.9 months, P < 0.05) and recurrence-free survival (13.2 ± 2.0 vs. 23.4 ± 2.5 months, P < 0.01), respectively. Multivariate Cox regression analyses identified CK19-positive expression to be an independent prognostic factor for both overall survival and recurrence-free survival.

CONCLUSIONS

DPHCC is a novel surgicopathologic entity that has a highly aggressive behavior and worse postoperative prognosis than pure HCC. Because the morphological features between DPHCC and conventional HCC overlap, we recommend that CK19 be routinely used in the pathological diagnosis of HCC for screening DPHCC.

Preoperative diagnosis of lymph node metastasis in biliary and pancreatic carcinomas: evaluation of the combination of multi-detector CT and serum CA19-9 level

BACKGROUND

It is difficult to diagnose lymph node metastasis in biliary and pancreas carcinomas before surgery.

AIM

The aim of this study was to assess the utility of the combination of multi-detector computed tomographic (MDCT) findings and serum carbohydrate antigen (CA)19-9 level in the diagnosis of lymph node metastasis in biliary and pancreas carcinomas.

METHODS

The subjects were 139 patients with biliary and pancreas carcinomas who underwent surgical resection. We calculated the positive predictive values (PPV), sensitivities, specificities, positive likelihood ratios (PLR) and accuracies of diagnosis by MDCT alone, serum CA19-9 level alone, and their combination.

RESULTS

The PPV and sensitivity were higher for node metastasis in hepatoduodenal ligament than in common hepatic artery (CHA) or para-aortic region (PAR). Specificity, accuracy and PLR were highest for CHA in biliary carcinoma. With pancreatic carcinoma, PLR was slightly higher in PAR compared to other regions. The sensitivity of CA19-9 for node metastasis was higher than that of MDCT, while the PPV, specificity, accuracy and PLR were low for both biliary and pancreas carcinoma. The combination of positive CT findings and high CA19-9 level had the highest positive rate for node metastasis for both types of carcinomas. Nodes around the supra-mesenteric vein could not be fully observed on CT.

CONCLUSION

The combination of high-resolution MDCT and CA19-9 is useful for the diagnosis of lymph node metastasis in biliary and pancreas carcinomas.

Cholangiocarcinoma: A position paper by the Italian Society of Gastroenterology (SIGE), the Italian Association of Hospital Gastroenterology (AIGO), the Italian Association of Medical Oncology (AIOM) and the Italian Association of Oncological Radiotherapy (AIRO)

The incidence of Cholangiocellular carcinoma (CCA) is increasing, due to a sharp increase of the intra-hepatic form. Evidence-ascertained risk factors for CCA are primary sclerosing cholangitis, Opistorchis viverrini infection, Caroli disease, congenital choledocal cist, Vater ampulla adenoma, bile duct adenoma and intra-hepatic lithiasis. Obesity, diabetes, smoking, abnormal biliary-pancreatic junction, bilio-enteric surgery, and viral cirrhosis are emerging risk factors, but their role still needs to be validated. Patients with primary sclerosing cholangitis should undergo surveillance, even though a survival benefit has not been clearly demonstrated. CCA is most often diagnosed in an advanced stage, when therapeutic options are limited to palliation. Diagnosis of the tumor is often difficult and multiple imaging techniques should be used, particularly for staging. Surgery is the standard of care for resectable CCA, whilst liver transplantation should be considered only in experimental settings. Metal stenting is the standard of care in inoperable patients with an expected survival >4 months. Gemcitabine or platinum analogues are recommended in advanced CCA whilst there are no validated neo-adjuvant treatments or second-line chemotherapies. Even though promising results have been obtained in CCA with radiotherapy, further randomized controlled trials are needed.