Pathogenesis, diagnosis and treatment of premalignant and malignant stages of cholangiocarcinoma in primary sclerosing cholangitis

Surveillance MRI is associated with improved survival in patients with primary sclerosing cholangitis

BACKGROUND

The benefits of regular surveillance imaging for cholangiocarcinoma in patients with primary sclerosing cholangitis (PSC) are unclear. Hence, we aimed to evaluate the impact of regular magnetic resonance cholangiopancreatography (MRCP) on outcomes of patients with PSC in Australia, where the practice of MRCP surveillance is variable.

METHODS

The relationship between MRCP surveillance and survival outcomes was assessed in a multicenter, retrospective cohort of patients with PSC from 9 tertiary liver centers in Australia. An inverse probability of treatment weighting approach was used to balance groups across potentially confounding covariates.

RESULTS

A total of 298 patients with PSC with 2117 person-years of follow-up were included. Two hundred and twenty patients (73.8%) had undergone MRCP surveillance. Regular surveillance was associated with a 71% reduced risk of death on multivariate weighted Cox analysis (HR: 0.29, 95% CI: 0.14-0.59, p < 0.001) and increased likelihood of having earlier endoscopic retrograde cholangiopancreatography from the date of PSC diagnosis in patients with a dominant stricture (p < 0.001). However, survival posthepatobiliary cancer diagnosis was not significantly different between both groups (p = 0.74). Patients who had surveillance of less than 1 scan a year (n = 41) had comparable survival (HR: 0.46, 95% CI 0.16-1.35, p = 0.16) compared to patients who had surveillance at least yearly (n = 172).

CONCLUSIONS

In this multicenter cohort study that employed inverse probability of treatment weighting to minimize selection bias, regular MRCP was associated with improved overall survival in patients with PSC; however, there was no difference in survival after hepatobiliary cancer diagnosis. Further prospective studies are needed to confirm the benefits of regular MRCP and optimal imaging interval in patients with PSC.

Tumor ratio of unsaturated to saturated sulfatide species is associated with disease-free survival in intrahepatic cholangiocarcinoma

PURPOSE

Cholangiocarcinoma (CCA) is a malignancy arising from the bile duct epithelium and has a poor outcome. Sulfatides are lipid components of lipid rafts, and are implicated in several cancer types. In the liver, sulfatides are specifically present in the bile ducts. Here, sulfatide abundance and composition were analyzed using mass spectrometry imaging in intrahepatic CCA (iCCA) tumor tissue, and correlated with tumor biology and clinical outcomes.

METHODS

Sulfatides were analyzed in iCCA (n = 17), hepatocellular carcinoma (HCC, n = 10) and colorectal liver metastasis (CRLM, n = 10) tumor samples, as well as tumor-distal samples (control, n = 16) using mass spectrometry imaging. Levels of sulfatides as well as the relative amount in structural classes were compared between groups, and were correlated with clinical outcomes for iCCA patients.

RESULTS

Sulfatide localization was limited to the respective tumor areas and the bile ducts. Sulfatide abundance was similar in iCCA and control tissue, while intensities were notably higher in CRLM in comparison with control (18-fold, P < 0.05) and HCC tissue (47-fold, P < 0.001). Considerable variation in sulfatide abundance was observed in iCCA tumors. A high ratio of unsaturated to saturated sulfatides was associated with reduced disease-free survival (10 vs. 20 months) in iCCA. The sulfatide pattern in HCC deviated from the other groups, with a higher relative abundance of odd- versus even-chain sulfatides.

CONCLUSION

Sulfatides were found in tumor tissue of patients with iCCA, with sulfatide abundance per pixel being similar to bile ducts. In this explorative study, sulfatide abundance was not related to overall survival of iCCA patients. A high ratio of unsaturated to saturated sulfatides was associated with earlier tumor recurrence in patients with iCCA.

Prognostic influence for hilar cholangiocarcinoma and comparisons of prognostic values of Mayo staging and TNM staging systems

The study was designed to discuss the effect of stratification factors in the Mayo staging on the prognosis of hilar cholangiocarcinoma (HCCA) patients, and to evaluate the predictive value of the Mayo staging on the prognosis. The Kaplan-Meier survival curve and Log-rank test were used to perform univariate analysis on each index and obtain statistically significant influencing factors. The Kaplan-Meier survival curve and Log-rank test were used to analyze the correlation between the two staging systems and the survival period. The receiver operating characteristic (ROC) curves were used for each single staging system trend analysis, and comparison of their curve area to determine prognosis prediction ability for patients with HCCA. According to Kaplan-Meier survival curve changes and Log-rank test results, it was found that both staging systems were correlated with the survival time of the patients (P < .001). Through a pairwise comparison within the stages, it was found that the heterogeneity between the stages within the Mayo staging is very good, which was better than the TNM staging. A single trend analysis of the prognostic assessment capabilities of the two systems found that the area under the ROC curve of Mayo staging system (AUC = 0.587) was the largest and better than the TNM staging system (AUC = 0.501). Mayo staging can be used for preoperative patient prognosis assessment which can provide better stratification ability based on a single-center small sample study, and the predictive value is better than TNM staging.

Screening potential biomarkers of cholangiocarcinoma based on gene chip meta-analysis and small-sample experimental research

Cholangiocarcinoma (CCA) is a rare malignant tumor associated with poor prognosis. This study aimed to identify CCA biomarkers by investigating differentially expressed genes (DEGs) between CCA patients and healthy subjects obtained from the Gene Expression Omnibus database. Bioinformatics tools, including the Illumina BaseSpace Correlation Engine (BSCE) and Gene Expression Profiling Interactive Analysis (GEPIA), were used. The initial DEGs from GSE26566, GSE31370, and GSE77984 were analyzed using GEO2R and Venn, and protein–protein interaction networks were constructed using STRING. The BSCE was applied to assess curated CCA studies to select additional DEGs and them DEGs across the 10 biosets, which was supported by findings in the literature. The final 18 DEGs with clinical significance for CCA were further verified using GEPIA. These included CEACAM6, EPCAM, LAMC2, MMP11, KRT7, KRT17, KRT19, SFN, and SOX9, which were upregulated, and ADH1A, ALDOB, AOX1, CTH, FGA, FGB, FGG, GSTA1, and OTC, which were downregulated in CCA patients. Among these 18 genes, 56 groups of genes (two in each group) were significantly related, and none were independently and differentially expressed. The hub genes FGA, OTC, CTH, and MMP11, which were most correlated with the 18 DEGs, were screened using STRING. The significantly low expression of FGA, OTC, and CTH and significantly high expression of MMP11 were verified by immunohistochemical analysis. Overall, four CCA biomarkers were identified that might regulate the occurrence and development of this disease and affect the patient survival rate, and they have the potential to become diagnostic and therapeutic targets for patients with CCA.

Outcome after resection for perihilar cholangiocarcinoma in patients with primary sclerosing cholangitis: an international multicentre study

BACKGROUND

Resection for perihilar cholangiocarcinoma (pCCA) in primary sclerosing cholangitis (PSC) has been reported to lead to worse outcomes than resection for non-PSC pCCA. The aim of this study was to compare prognostic factors and outcomes after resection in patients with PSC-associated pCCA and non-PSC pCCA.

METHODS

The international retrospective cohort comprised patients resected for pCCA from 21 centres (2000-2020). Patients operated with hepatobiliary resection, with pCCA verified by histology and with data on PSC status, were included. The primary outcome was overall survival. Secondary outcomes were disease-free survival and postoperative complications.

RESULTS

Of 1128 pCCA patients, 34 (3.0%) had underlying PSC. Median overall survival after resection was 33 months for PSC patients and 29 months for non-PSC patients (p = .630). Complications (Clavien-Dindo grade ≥ 3) were more frequent in PSC pCCA (71% versus 44%, p = .003). The rate of posthepatectomy liver failure (21% versus 17%, p = .530) and 90-day mortality (12% versus 13%, p = 1.000) was similar for PSC and non-PSC patients.

CONCLUSION

Median overall survival after resection for pCCA was similar in patients with underlying PSC and non-PSC patients. Complications were more frequent after resection for PSC-associated pCCA, with no difference in postoperative mortality.

Apolipoprotein B Is Associated With the Microenvironment of Cholangiocarcinoma

Background

Cholangiocarcinoma (CCA) is a kind of devastating malignancy, which is correlated with the extremely high mortality. Due to the occult pathogenesis of CCA, most patients are diagnosed in the advanced stage. However, the efficacy of chemotherapy and immunotherapy is limited for these patients. The cause for this phenomenon is unclear, the recent researches indicate that it could be related to predisposing genetic factors and tumor microenvironment (TME) changes. The TME is created by the tumor and dominated by tumor-induced interactions. And the tumor prognosis could be influenced by the extent of infiltrating immune cells and stromal cells in TME.

Materials and methods

The abundance ratio of immune cells for each sample was obtained via the CIBERSORT algorithm, and we used ESTIMATE score system to calculate the immune and stromal scores in CCA. The CCA cases in TCGA database were categorized into high and low score groups according to their immune/stromal scores. And then, we identified the differential expressed genes (DEGs) in two groups. Functional enrichment analysis and protein‐protein interaction networks were carried out for DEGs. Interestingly, we found out that apolipoprotein B (APOB) is the most down-regulated among these genes. Then we performed the immunohistochemistry staining of APOB in a CCA tumor microarray which contained 100 CCA cases, APOB was down-regulated in CCA samples. Thus, we evaluated the APOB function in the TME of CCA through TIMER.

Results and Conclusion

The results demonstrate that the infiltration degree of immune cells in CCA could be influenced by the expression of APOB, and the APOB expression could be mediated by DNA methylation. Our study not only indicates APOB is a potential target for CCA immunotherapy but also provides new ideas for researchers to explore the immunotherapy of various tumors.

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

BACKGROUND

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

OBJECTIVE

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

PATIENTS AND METHODS

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

RESULTS

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

CONCLUSION

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

The impact of primary sclerosing cholangitis or inflammatory bowel disease on cholangiocarcinoma phenotype, therapy, and survival

Background and Aim

Primary sclerosing cholangitis (PSC), with or without inflammatory bowel disease (IBD), confers the risk of cholangiocarcinoma. Isolated IBD may be an independent risk factor for cholangiocarcinoma. We sought to compare cholangiocarcinoma phenotype and outcomes between patients with PSC, IBD, and neither.

Methods

Patients with malignancy were separated into cohorts by the presence of PSC and IBD. Data regarding demographics, clinical presentation, therapeutic regimens, and survival were collected. Statistical analysis was carried out using GraphPad and R‐Studio.

Results

Of 946 patients, 22 had PSC, and 18 had isolated IBD. PSC and IBD patients were younger than controls (P < 0.001, P = 0.01). Cholangiocarcinoma prevalence was estimated at 0.01% for IBD patients, 0.6% for PSC patients, and 0.002% for all other patients. All cohorts most often presented at stage 4. PSC patients presented more often at stage 3 (P = 0.04) and with perihilar disease (P = 0.001). Patients with PSC or IBD received less chemotherapy (P = 0.004, 0.01). Median overall survivals were 15 months (PSC), 11 months (IBD), and 10 months (controls) (P = 0.79). Patients with intrahepatic tumors had longer survival (P < 0.001). Curative intent resection improved survival in all cohorts (P < 0.001). Multivariate regression identified resection as a predictor of improved survival. Extrahepatic, perihilar, gallbladder, and unspecified biliary tumors were predictors of death.

Conclusions

Cholangiocarcinoma presents at a late stage and portends dismal survival regardless of PSC or IBD status. Survival was dependent on tumor location and surgical resection. These data suggest that efforts should focus on developing protocols that are able to detect and treat cholangiocarcinoma in high‐risk populations (PSC) at an early stage.

An Overview on Primary Sclerosing Cholangitis

Primary sclerosing cholangitis is a progressive liver disease characterized by chronic inflammation leading to liver fibrosis and cirrhosis. Even though the exact pathogenesis is still unclear, a combination of autoimmune, environmental, and ischemic factors could explain certain aspects of the disease. The most important diagnostic step is cholangiography, which can be obtained either by endoscopic retrograde cholangiopancreatography (ERCP), magnetic resonance cholangiography (MRCP as the gold standard), or percutaneous transhepatic cholangiography. It shows multifocal short biliary duct strictures leading to the "beaded" aspect. Cholangiocarcinoma and colorectal adenocarcinoma are the most feared complications in patients with Primary sclerosing cholangitis (PSC). Continuous screening consists of annual clinical, biochemical, and ultrasound assessments in asymptomatic patients and annual colonoscopy in patients with PSC and inflammatory bowel disease. In newly diagnosed patients with PSC, colonoscopy is mandatory and, if negative, then, a repeat colonoscopy should be performed in 3-5 years. The lack of efficient curative medical treatment makes invasive treatments such as liver transplant and endoscopy the mainstream for managing PSC and its complications. Until now, even though only ursodeoxycholic acid has shown a moderate clinical, biochemical, and even histological improvement, it has no significant influence on the risk of cholangiocarcinoma, liver transplant need, or death risk and it is no longer recommended in treating early PSC. Further studies are in progress to establish the effect of molecular-targeted therapies in PSC.

Emerging therapies in primary sclerosing cholangitis: pathophysiological basis and clinical opportunities

Primary sclerosing cholangitis (PSC) is a progressive liver disease, histologically characterized by inflammation and fibrosis of the bile ducts, and clinically leading to multi-focal biliary strictures and with time cirrhosis and liver failure. Patients bear a significant risk of cholangiocarcinoma and colorectal cancer, and frequently have concomitant inflammatory bowel disease and autoimmune disease manifestations. To date, no medical therapy has proven significant impact on clinical outcomes and most patients ultimately need liver transplantation. Several treatment strategies have failed in the past and whilst prescription of ursodeoxycholic acid (UDCA) prevails, controversy regarding benefits remains. Lack of statistical power, slow and variable disease progression, lack of surrogate biomarkers for disease severity and other challenges in trial design serve as critical obstacles in the development of effective therapy. Advances in our understanding of PSC pathogenesis and biliary physiology over recent years has however led to a surge of clinical trials targeting various mechanistic compartments and currently raising hopes for imminent changes in patient management. Here, in light of pathophysiology, we outline and critically evaluate emerging treatment strategies in PSC, as tested in recent or ongoing phase II and III trials, stratified per a triad of targets of nuclear and membrane receptors regulating bile acid metabolism, immune modulators, and effects on the gut microbiome. Furthermore, we revisit the UDCA trials of the past and critically discuss relevant aspects of clinical trial design, including how the choice of endpoints, alkaline phosphatase in particular, may affect the future path to novel, effective PSC therapeutics.