Worldwide Incidence and Mortality of Biliary Tract Cancer

Endoluminal radiofrequency ablation with stenting versus stenting alone in patients with malignant biliary obstruction: a meta-analysis of randomized trials

BACKGROUND

Endoluminal radiofrequency ablation (RFA) is a palliative treatment for patients suffering from malignant biliary obstruction (MBO). We aimed to conduct a meta-analysis to evaluate the impact of RFA on stent patency, patient survival, and adverse events.

METHODS

Major databases were searched through December 2023 for patients who had undergone stenting with or without RFA for extrahepatic MBO. A random-effects model was used for analysis, with results expressed as relative risk ratios (RRs) with 95%CIs.

RESULTS

Nine RCTs involving 750 subjects with MBO (374 RFA plus stent vs. 376 stent only) were included. Meta-analysis revealed similar risks of stent patency at 3 months (RR 1.01, 95%CI 0.92-1.11; I 2 = 4%) for RFA plus stenting vs. stent only. Meta-analysis showed improved survival at 6 months (RR 0.84, 95%CI 0.73-0.96; I 2 = 21%; P = 0.01) for RFA plus stenting vs. stent only. Subgroup analysis comparing plastic vs. uncovered metal stents showed that stent patency was unaffected at 3 months (RR 1.06, 95%CI 0.91-1.23; I 2 = 17%). Subgroup analysis showed that patients with cholangiocarcinoma experienced an overall survival benefit with RFA plus stenting vs. stenting alone (P < 0.001); however, stent patency remained unaffected (P = 0.08). An increased incidence of cholecystitis was noted with RFA plus stenting vs. stenting alone (5.1% [95%CI 3.1%-7.8%] vs. 0.3% [95%CI 0.01%-1.5%], respectively).

CONCLUSION

Combining endoluminal RFA and stenting may improve overall survival in patients with MBO. RFA did not significantly impact stent patency.

Digestive cancers: mechanisms, therapeutics and management

Cancers of the digestive system are major contributors to global cancer-associated morbidity and mortality, accounting for 35% of annual cases of cancer deaths. The etiologies, molecular features, and therapeutic management of these cancer entities are highly heterogeneous and complex. Over the last decade, genomic and functional studies have provided unprecedented insights into the biology of digestive cancers, identifying genetic drivers of tumor progression and key interaction points of tumor cells with the immune system. This knowledge is continuously translated into novel treatment concepts and targets, which are dynamically reshaping the therapeutic landscape of these tumors. In this review, we provide a concise overview of the etiology and molecular pathology of the six most common cancers of the digestive system, including esophageal, gastric, biliary tract, pancreatic, hepatocellular, and colorectal cancers. We comprehensively describe the current stage-dependent pharmacological management of these malignancies, including chemo-, targeted, and immunotherapy. For each cancer entity, we provide an overview of recent therapeutic advancements and research progress. Finally, we describe how novel insights into tumor heterogeneity and immune evasion deepen our understanding of therapy resistance and provide an outlook on innovative therapeutic strategies that will shape the future management of digestive cancers, including CAR-T cell therapy, novel antibody-drug conjugates and targeted therapies.

Metagenomic characterization of oral microbiome signatures to predict upper gastrointestinal and pancreaticobiliary cancers: a case-control study

BACKGROUND

This study investigated the oral microbiome signatures associated with upper gastrointestinal (GI) and pancreaticobiliary cancers.

METHODS

Saliva samples from cancer patients and age- and sex-matched healthy controls were analyzed using 16S rRNA-targeted sequencing, followed by comprehensive bioinformatics analysis.

RESULTS

Significant dissimilarities in microbial composition were observed between cancer patients and controls across esophageal cancer (EC), gastric cancer (GC), biliary tract cancer (BC), and pancreatic cancer (PC) groups (R2 = 0.067, = 0.075, = 0.068, and = 0.044; p = 0.001, = 0.001, = 0.002, and = 0.004, respectively). Additionally, the oral microbiome composition significantly differed by the four cancer sites (p = 0.001 for EC vs. GC, EC vs. BC, EC vs. PC, GC vs. BC, and GC vs. PC; p = 0.013 for BC vs. PC). We built oral metagenomic classifiers to predict cancer and selected specific microbial taxa with diagnostic properties. For EC, the classifier differentiated cancer patients and controls with good accuracy (area under the curve [AUC] = 0.791) and included three genera: Akkermansia, Escherichia-Shigella, and Subdoligranulum. For GC, the classifier exhibited high discriminative power (AUC = 0.961); it included five genera (Escherichia-Shigella, Gemella, Holdemanella, Actinomyces, and Stomatobaculum) and three species (Eubacterium sp. oral clone EI074, Ruminococcus sp. Marseille-P328, and Leptotrichia wadei F0279). However, microbial taxa with diagnostic features for BC and PC were not identified.

CONCLUSIONS

These findings suggested that the oral microbiome composition may serve as an indicator of tumorigenesis in upper GI and pancreaticobiliary cancers. The development of oral metagenomic classifiers for EC and GC demonstrates the potential value of microbial biomarkers in cancer screening.

The Immune Landscape and Its Potential for Immunotherapy in Advanced Biliary Tract Cancer

Biliary tract cancers (BTC) are a highly heterogeneous group of cancers at the genomic, epigenetic and molecular levels. The vast majority of patients initially present at an advanced (unresectable) disease stage due to a lack of symptoms and an aggressive tumour biology. Chemotherapy has been the mainstay of treatment in patients with advanced BTC but the survival outcomes and prognosis remain poor. The addition of immune checkpoint inhibitors (ICI) to chemotherapy have shown only a marginal benefit over chemotherapy alone due to the complex tumour immune microenvironment of these cancers. This review appraises our current understanding of the immune landscape of advanced BTC, including emerging transcriptome-based classifications, highlighting the mechanisms of immune evasion and resistance to ICI and their therapeutic implications. It describes the shifting treatment paradigm from traditional chemotherapy to immunotherapy combinations as well as the potential biomarkers for predicting response to ICI.

An analysis of the global burden of gallbladder and biliary tract cancer attributable to high BMI in 204 countries and territories: 1990-2021

Background

Gallbladder and biliary tract cancers (GBTCs) are aggressive with poor prognosis, often undetected until advanced stages. High Body Mass Index (BMI) is a significant risk factor, contributing substantially to GBTC mortality and Disability-Adjusted Life Years (DALYs). This study aimed to quantify the global burdens of GBTCs attributable to high BMI from 1990 to 2021, thereby developing more rational prevention and treatment strategies for GBTC.

Methods

Data were extracted from the Global Burden of Disease (GBD) 2021. Age-standardized rates of mortality (ASMR), and DALYs (ASDR) for GBTCs due to high BMI were calculated by years, genders, ages, geographical locations, and sociodemographic index (SDI). The estimated annual percentage change (EAPC) was calculated to evaluate the temporal trends from 1990 to 2021. Decomposition and frontier analyses were conducted to understand the driving forces behind burden changes and to identify top-performing countries. Inequality analysis was conducted to assess burden disparities across different SDI levels. The disease burden was forecasted through 2035 using the Bayesian age period cohort (BAPC) model.

Results

Globally, ASMR and ASDR for GBTCs related to high BMI decreased from 1990 to 2021; however, the absolute number of deaths and DALYs cases more than doubled, and similar patterns are projected to continue over the next 14 years in the absence of intervention. High SDI regions showed higher burdens due to higher obesity rates, population growth, and aging, while low SDI regions faced higher EAPCs due to limited resources. Moreover, this inequality has become more significant. Females were more susceptible across all age groups. Notable variations in burden management were observed among countries, with some low SDI nations demonstrating superior performance to high SDI countries.

Conclusion

Despite the decline in rates, the burden of GBTCs attributable to high BMI remains substantial, underscoring the need for targeted prevention strategies for high BMI, particularly in high SDI regions. Gender and age disparities necessitate tailored health interventions.

Impact of high body mass index on gallbladder and biliary tract cancer burden in China: a comprehensive analysis of trends from 1990 to 2021

BACKGROUND

Gallbladder and biliary tract cancer (GBTC) is a significant health burden in China, exacerbated by the rising prevalence of high body mass index (BMI). Understanding the trends and factors contributing to mortality and disability associated with GBTC is crucial for targeted public health interventions.

METHODS

We utilized data from the Global Burden of Disease (GBD) Study to assess the burden of GBTC attributable to high BMI in China from 1990 to 2021. Age-standardized rates of deaths, disability-adjusted life years (DALYs), years lived with disability (YLDs), and years of life lost (YLLs) were analyzed. Joinpoint regression and decomposition analyses were conducted to evaluate trends and identify contributing factors, including aging, population growth, and epidemiological changes. Gender-specific differences were also assessed.

RESULTS

In 2021, GBTC deaths attributable to high BMI in China reached 4,053, with males experiencing a higher overall burden than females, particularly in older age groups. While females showed a higher mortality and overall burden in the 60 to 79 age range, this trend reversed in older age brackets, with males experiencing steeper increases in mortality and disability-related indicators beyond age 80. The age-standardized DALYs rate mirrored this pattern, with higher rates in males in advanced age groups. From 1990 to 2021, China saw a steady increase in GBTC burden attributable to high BMI, contrasting with a global decline. Joinpoint analysis indicated marked rises in mortality and DALYs rates after 2005, especially in males. Decomposition analysis identified population growth and aging as major drivers of increased deaths, while epidemiological changes primarily contributed to rising DALYs, with a stronger impact observed in males.

CONCLUSIONS

The burden of GBTC attributable to high BMI in China has increased substantially over the last three decades, driven by population growth, aging, and epidemiological shifts. The trends highlight a growing gender disparity, with males experiencing a greater rise in mortality and disability. Public health strategies targeting obesity and metabolic risk factors are critical to mitigating the increasing GBTC burden.

The Epidemiology of Biliary Tract Cancer and Associated Prevalence of MDM2 Amplification: A Targeted Literature Review

Biliary tract cancer (BTC) is a rare and aggressive malignancy that is anatomically classified as gallbladder cancer (GBC), extra- and intra-hepatic cholangiocarcinoma (eCCA and iCCA) and ampullary cancer (AC). BTC is often diagnosed at an advanced stage when treatment options are limited and patients have a poor prognosis, so the identification of new drug targets is of critical importance. BTC is molecularly diverse and harbours different therapeutically actionable biomarkers, including mouse double minute 2 homolog (MDM2), which is currently being investigated as a drug target. The aim of this targeted review was to evaluate and synthesise evidence on the epidemiology of BTC and its subtypes in different geographic regions and on the frequency of MDM2 amplifications in BTC tumours. Epidemiological studies (N = 33) consistently demonstrated high incidence rates in South and Central Asia for BTC overall (up to 9.00/100,000) and for all subtypes, with much lower rates in Europe and the US. Among the different types of BTC, the highest global incidence was observed for CCA, mainly driven by iCCA (1.4/100,000), followed by GBC (1.2/100,000) and AC (0.18-0.93 per 100,000). Studies of MDM2 in BTC (N = 19) demonstrated variable frequency of MDM2 amplification according to subtype, with consistently high MDM2 amplification rates in GBC (up to 17.5%), and lower rates in CCA (up to 4.4%). The results from this literature review highlight the geographic heterogeneity of BTC and the need for standardised clinicopathologic assessment and reporting to allow cross-study comparisons.

Epidemiology of biliary tract cancer in China: A narrative review

Biliary tract cancer (BTC) is a group of rare malignancies that affect the gallbladder and bile ducts. Although rare, BTC is becoming a significant public health burden in China, particularly among males and older individuals. The increasing trends in BTC incidence and mortality in China are influenced by various demographic, environmental, and lifestyle factors. In this review, we examine available epidemiological data on the incidence, mortality, prognosis, and trends of different BTC subtypes in China. We also discuss the challenges and opportunities for improving the prevention, diagnosis, and management of BTC in China, and identify areas for further research and intervention. The article aims to provide a better understanding of the epidemiological features of BTC in China and to inform public health strategies and clinical practice.

Antibody-Drug Conjugates and Their Potential in the Treatment of Patients with Biliary Tract Cancer

Background: Biliary tract cancers (BTCs) are aggressive in nature, often presenting asymptomatically until they are diagnosed at an advanced stage. Surgical resection or liver transplantation are potential curative options. However, a large proportion of patients present with incurable locally advanced or metastatic disease and most of these patients are only eligible for palliative chemotherapy or best supportive care. More recently, targeted therapies have proven beneficial in a molecularly selected subgroup of patients with cholangiocarcinoma who have progressed on previous lines of systemic treatment. However, only a minority of patients with BTCs whose tumours harbour specific molecular alterations can access these therapies. Methods: In relation to ADCs, studies regarding use of antibody-drug conjugates in cancer, particularly in BTCs, were searched in Embase (1974 to 2024) and Ovid MEDLINE(R) (1946 to 2024) to obtain relevant articles. Examples of current clinical trials utilising ADC treatment in BTCs were extracted from the ClinicalTrials.gov trial registry. Conclusions: Overall, this review has highlighted that ADCs have shown encouraging outcomes in cancer therapy, and this should lead to further research including in BTCs, where treatment options are often limited. The promising results observed with ADCs in various cancers underscore their potential as a transformative approach in oncology, warranting continued exploration and development and the need for education on the management of their specific toxicities. By addressing current challenges and optimising ADC design and application, future studies could potentially improve treatment outcomes for patients with BTCs and beyond, potentially in both early and advanced stage settings.

Endoscopic Ultrasound and Intraductal Ultrasound in the Diagnosis of Biliary Tract Diseases: A Narrative Review

Endoscopic ultrasound (EUS) and intraductal ultrasound (IDUS) play very important roles in the field of biliary tract disease. Because of their excellent spatial resolution, the detection of small lesions and T- or N-staging of tumors have become possible. Additionally, contrast-enhanced EUS and the new imaging technique of detective flow imaging are reported to be useful for differential diagnosis. Furthermore, EUS-guided tissue acquisition is used not only for pathological diagnosis but also to collect tissue samples for cancer genome profiling. This review provides an overview of diagnosis utilizing the features and techniques of EUS and IDUS.

Pertuzumab Plus Trastuzumab in Patients With Biliary Tract Cancer With ERBB2/3 Alterations: Results From the Targeted Agent and Profiling Utilization Registry Study

PURPOSE

Targeted Agent and Profiling Utilization Registry is a phase II basket trial evaluating the antitumor activity of commercially available targeted agents in patients with advanced cancer and genomic alterations known to be drug targets. Results of a cohort of patients with biliary tract cancer (BTC) with ERBB2/3 amplification, overexpression, or mutation treated with pertuzumab plus trastuzumab are reported.

METHODS

Eligible patients had advanced BTC, measurable disease (RECIST v1.1), Eastern Cooperative Oncology Group performance status 0-2, adequate organ function, tumors with ERBB2/3 alterations, and a lack of standard treatment options. Simon's two-stage design was used with a primary end point of disease control (DC), defined as objective response (OR) or stable disease of at least 16+ weeks duration (SD16+) according to RECIST v1.1. Secondary end points included OR, progression-free survival, overall survival, duration of response, duration of stable disease, and safety.

RESULTS

Twenty-nine patients were enrolled from February 2017 to January 2022, and all had advanced BTC with an ERBB2/3 alteration. One patient was not evaluable for efficacy. One complete response, eight partial responses, and two SD16+ were observed for DC and OR rates of 40% (90% CI, 27 to 100) and 32% (95% CI, 16 to 52), respectively. The null hypothesis of 15% DC rate was rejected (P = .0015). Four patients had at least one grade 3 adverse event (AE) or serious AE at least possibly related to treatment: anemia, diarrhea, infusion-related reaction, and fatigue.

CONCLUSION

Pertuzumab plus trastuzumab met prespecified criteria to declare a signal of activity in patients with BTC and ERBB2/3 amplification, overexpression, or mutation.

Pan-Asian adapted ESMO Clinical Practice Guidelines for the diagnosis, treatment and follow-up of patients with biliary tract cancer

The European Society for Medical Oncology (ESMO) Clinical Practice Guidelines for the diagnosis, treatment and follow-up of patients with biliary tract cancer (BTC), published in late 2022 were adapted in December 2023, according to established standard methodology, to produce the Pan-Asian adapted (PAGA) ESMO consensus guidelines for the management of Asian patients with BTC. The adapted guidelines presented in this manuscript represent the consensus opinions reached by a panel of Asian experts in the treatment of patients with BTC representing the oncological societies of China (CSCO), Indonesia (ISHMO), India (ISMPO), Japan (JSMO), Korea (KSMO), Malaysia (MOS), the Philippines (PSMO), Singapore (SSO), Taiwan (TOS) and Thailand (TSCO), co-ordinated by ESMO and the Taiwan Oncology Society (TOS). The voting was based on scientific evidence and was independent of the current treatment practices, drug access restrictions and reimbursement decisions in the different regions of Asia. Drug access and reimbursement in the different regions of Asia are discussed separately in the manuscript. The aim is to provide guidance for the optimisation and harmonisation of the management of patients with BTC across the different countries and regions of Asia, drawing on the evidence provided by both Western and Asian trials, whilst respecting the differences in screening practices and molecular profiling, as well as age and stage at presentation. Attention is drawn to the disparity in the drug approvals and reimbursement strategies, between the different countries.

RNA-binding protein transcripts as potential biomarkers for detecting Primary Sclerosing Cholangitis and for predicting its progression to Cholangiocarcinoma

Primary Sclerosing Cholangitis (PSC) is a persistent inflammatory liver condition that affects the bile ducts and is commonly diagnosed in young individuals. Despite efforts to incorporate various clinical, biochemical and molecular parameters for diagnosing PSC, it remains challenging, and no biomarkers characteristic of the disease have been identified hitherto. PSC is linked with an uncertain prognosis, and there is a pressing need to explore multiomics databases to establish a new biomarker panel for the early detection of PSC's gradual progression into Cholangiocarcinoma (CCA) and for the development of effective therapeutic interventions. Apart from non-coding RNAs, other components of the Ribonucleoprotein (RNP) complex, such as RNA-Binding Proteins (RBPs), also hold great promise as biomarkers due to their versatile expression in pathological conditions. In the present review, an update on the RBP transcripts that show dysregulated expression in PSC and CCA is provided. Moreover, by utilizing a bioinformatic data mining approach, we give insight into those RBP transcripts that also exhibit differential expression in liver and gall bladder, as well as in body fluids, and are promising as biomarkers for diagnosing and predicting the prognosis of PSC. Expression data were bioinformatically extracted from public repositories usingTCGA Bile Duct Cancer dataset for CCA and specific NCBI GEO datasets for both PSC and CCA; more specifically, RBPs annotations were obtained from RBP World database. Interestingly, our comprehensive analysis shows an elevated expression of the non-canonical RBPs, FANCD2, as well as the microtubule dynamics regulator, ASPM, transcripts in the body fluids of patients with PSC and CCA compared with their respective controls, with the same trend in expression being observed in gall bladder and liver cancer tissues. Consequently, the manipulation of tissue expression of RBP transcripts might be considered as a strategy to mitigate the onset of CCA in PSC patients, and warrants further experimental investigation. The analysis performed herein may be helpful in the identification of non-invasive biomarkers for the early detection of PSC and for predicting its progression into CCA. In conclusion, future clinical research should investigate in more depth the full potential of RBP transcripts as biomarkers for human pathologies.

O-GlcNAcylation Facilitates the Interaction between Keratin 18 and Isocitrate Dehydrogenases and Potentially Influencing Cholangiocarcinoma Progression

Glycosylation plays a pivotal role in the intricate landscape of human cholangiocarcinoma (CCA), actively participating in key pathophysiological processes driving tumor progression. Among the various glycosylation modifications, O-linked β-N-acetyl-glucosamine modification (O-GlcNAcylation) emerges as a dynamic regulator influencing diverse tumor-associated biological activities. In this study, we employed a state-of-the-art chemical proteomic approach to analyze intact glycopeptides, unveiling the critical role of O-GlcNAcylation in orchestrating Keratin 18 (K18) and its interplay with tricarboxylic acid (TCA) cycle enzymes, specifically isocitrate dehydrogenases (IDHs), to propel CCA progression. Our findings shed light on the mechanistic intricacies of O-GlcNAcylation, revealing that site-specific modification of K18 on Ser 30 serves as a stabilizing factor, amplifying the expression of cell cycle checkpoints. This molecular event intricately fosters cell cycle progression and augments cellular growth in CCA. Notably, the interaction between O-GlcNAcylated K18 and IDHs orchestrates metabolic reprogramming by down-regulating citrate and isocitrate levels while elevating α-ketoglutarate (α-KG). These metabolic shifts further contribute to the overall tumorigenic potential of CCA. Our study thus expands the current understanding of protein O-GlcNAcylation and introduces a new layer of complexity to post-translational control over metabolism and tumorigenesis.

Evaluating the Therapeutic Potential of Durvalumab in Adults with Locally Advanced or Metastatic Biliary Tract Cancer: Evidence to Date

Advanced biliary tract cancers (BTCs) have historically been managed with chemotherapy but, in recent years, this treatment paradigm has begun to shift with the introduction of immune checkpoint inhibitors in addition to standard of care chemotherapy. The tumor microenvironment of BTC may be enriched with regulatory T lymphocytes and immune checkpoint expression in some patients. Durvalumab, an anti-programmed death ligand-1 (PD-L1) antibody, in combination with gemcitabine and cisplatin, has now received United States Food and Drug Administration approval for treatment of advanced BTC. Regulatory approval was based on the Phase III, randomized TOPAZ-1 trial that demonstrated survival benefit with addition of durvalumab to gemcitabine plus cisplatin compared to chemotherapy alone. The combination of chemotherapy and immunotherapy was well tolerated, and a subset of patients were able to achieve a durable response, with a 2-year overall survival rate of 23.6%. However, limitations remain in identifying which patients are most likely to benefit from immune checkpoint inhibition. Future study should aim to identify biomarkers predictive of substantial benefit, as well as the role of immune checkpoint inhibition in combination with targeted therapies and radiotherapy in the management of advanced BTC.

Differences in the incidence and mortality of digestive cancer between Global Cancer Observatory 2020 and Global Burden of Disease 2019

The burden of digestive cancers is increasing worldwide. The Global Cancer Observatory (GLOBOCAN) 2020 and the Global Burden of Disease (GBD) 2019 are two primary cancer databases, which have a significant impact on policy formulation and resource allocation. We aim to compare the incidence and mortality of digestive cancers between them. Digestive cancer (esophageal, stomach, colorectal, liver, gallbladder and pancreatic cancer) incidence was obtained from the Cancer Today and GBD 2019 result tool. The top five countries with the most or minor difference between GLOBOCAN 2020 and GBD 2019 in age-standardized incidence rates (ASIRs) of digestive cancers were identified. A systematic search on the incidence of specific digestive cancer in selected countries from PubMed and Embase was conducted, and 20 of 281 publications were included. The most significant differences in digestive cancers incidence were commonly found in Asian countries (70%), particularly Indonesia, Vietnam and Myanmar, located in Southeast Asia. The ASIRs for most digestive cancers, except liver cancer, in GLOBOCAN 2020 were higher than those in GBD 2019. Gallbladder cancer had the highest average ratio, followed by liver cancer. The most commonly used standard population was Segi's standard population, followed by the World Health Organization standard population. The data sources nor the processing methods of GLOBOCAN 2020 and GBD 2019 were not similar. Low- and middle-income countries without population-based cancer registries were more likely to have selection bias in data collection and amplify regional variations of etiological factors. Better judgments on the quality of cancer data can be made.

A Systematised Literature Review of Real-World Treatment Patterns and Outcomes in Unresectable Advanced or Metastatic Biliary Tract Cancer

BACKGROUND

Biliary tract cancers are rare aggressive malignancies typically diagnosed when the disease is metastatic or unresectable, precluding curative treatment.

OBJECTIVE

We aimed to identify treatment guidelines, real-world treatment patterns, and outcomes for unresectable advanced or metastatic biliary tract cancers in adult patients.

METHODS

Databases (MEDLINE, Embase, Cochrane Database of Systematic Reviews) were systematically searched between 1 January, 2000 and 25 November, 2021, and supplemented by hand searches. Eligible records were (1) treatment guidelines and (2) observational studies reporting real-world treatment outcomes, for unresectable advanced or metastatic biliary tract cancers. Only studies performed in the UK, Germany, France, Australia, Canada and South Korea were extracted, to moderate the number of records for synthesis while maintaining representation of a wide range of biliary tract cancer incidences.

RESULTS

A total of 66 relevant unique full-text records were extracted, including 16 treatment guidelines and 50 observational studies. Among guidelines, chemotherapies were most strongly recommended at first line (1L); the combination of gemcitabine and cisplatin (GEMCIS) was recommended as the standard of care in 1L. Recommendations for systemic chemotherapy in the second line (2L) conflicted because of uncertainties around survival benefit. Guidelines on further lines of treatment included a range of locoregional modalities and stenting or best supportive care without providing clear recommendations because of data paucity. Fifty observational studies reporting real-world treatment outcomes were extracted, of which 25 (50%) and 9 (18%) reported outcomes in 1L and 2L, respectively; 22 (44%) reported outcomes for treatments described as 'palliative'. In 1L, outcomes for systemic chemotherapy were most frequently described (23/25 studies), and GEMCIS was the most common systemic chemotherapy used (10/23 studies) in line with guidelines. Median overall survival with 1L systemic chemotherapy was < 12 months in most studies (16/23; range 4.7-22.3 months). Most 2L studies (10/11) described outcomes for systemic chemotherapy, most commonly for fluoropyrimidine-based regimen (5/10 studies). Median overall survival with 2L systemic chemotherapy was < 12 months in 5/10 studies (range 4.9-21.5 months). Median progression-free survival was reported more rarely than median overall survival. Some studies with small sample sizes or specifically selected patient populations (e.g. higher performance status, or patients who had already responded to treatment) achieved higher median overall survival.

CONCLUSIONS

At the time of this review, treatment options for unresectable advanced or metastatic biliary tract cancers confer poor real-world survival. For over a decade, GEMCIS remained the 1L standard of care, highlighting the lack of therapeutic innovation in this indication and the urgent unmet need for novel treatments with improved outcomes in this aggressive condition. Additional observational studies are needed to further understand the effectiveness of currently available treatments, as well as newly available therapies including the addition of immunotherapy in the evolving treatment landscape.

Molecular Analysis of Biliary Tract Cancers with the Custom 3' RACE-Based NGS Panel

The technique 3' rapid amplification of cDNA ends (3' RACE) allows for detection of translocations with unknown gene partners located at the 3' end of the chimeric transcript. We composed a 3' RACE-based RNA sequencing panel for the analysis of FGFR1-4 gene rearrangements, detection of activating mutations located within FGFR1-4, IDH1/2, ERBB2 (HER2), KRAS, NRAS, BRAF, and PIK3CA genes, and measurement of the expression of ERBB2, PD-L1, and FGFR1-4 transcripts. This NGS panel was utilized for the molecular profiling of 168 biliary tract carcinomas (BTCs), including 83 intrahepatic cholangiocarcinomas (iCCAs), 44 extrahepatic cholangiocarcinomas (eCCAs), and 41 gallbladder adenocarcinomas (GBAs). The NGS failure rate was 3/168 (1.8%). iCCAs, but not other categories of BTCs, were characterized by frequent FGFR2 alterations (17/82, 20.7%) and IDH1/2 mutations (23/82, 28%). Other potentially druggable events included ERBB2 amplifications or mutations (7/165, 4.2% of all successfully analyzed BTCs) and BRAF p.V600E mutations (3/165, 1.8%). In addition to NGS, we analyzed microsatellite instability (MSI) using the standard five markers and revealed this event in 3/158 (1.9%) BTCs. There were no instances of ALK, ROS1, RET, and NTRK1-3 gene rearrangements or MET exon 14 skipping mutations. Parallel analysis of 47 iCCA samples with the Illumina TruSight Tumor 170 kit confirmed good performance of our NGS panel. In conclusion, targeted RNA sequencing coupled with the 3' RACE technology is an efficient tool for the molecular diagnostics of BTCs.

A Practical Guide for the Systemic Treatment of Biliary Tract Cancer in Canada

Biliary tract cancers (BTC) are rare and aggressive tumors with poor prognosis. Radical surgery offers the best chance for cure; however, most patients present with unresectable disease, and among those receiving curative-intent surgery, recurrence rates remain high. While other locoregional therapies for unresectable disease may be considered, only select patients may be eligible. Consequently, systemic therapy plays a significant role in the treatment of BTC. In the adjuvant setting, capecitabine is recommended following curative-intent resection. In the neoadjuvant setting, systemic therapy has mostly been explored for downstaging in borderline resectable tumours, although evidence for its routine use is lacking. For advanced unresectable or metastatic disease, gemcitabine-cisplatin plus durvalumab has become the standard of care, while the addition of pembrolizumab to gemcitabine-cisplatin has also recently demonstrated improved survival compared to chemotherapy alone. Following progression on gemcitabine-cisplatin, several chemotherapy combinations and biomarker-driven targeted agents have been explored. However, the optimum regimen remains unclear, and access to targeted agents remains challenging in Canada. Overall, this article serves as a practical guide for the systemic treatment of BTC in Canada, providing valuable insights into the current and future treatment landscape for this challenging disease.