Molecular profiling of intrahepatic cholangiocarcinoma: the search for new therapeutic targets

The Recent Trends of Systemic Treatments and Locoregional Therapies for Cholangiocarcinoma

Cholangiocarcinoma (CCA) is a hepatic malignancy that has a rapidly increasing incidence. CCA is anatomically classified into intrahepatic (iCCA) and extrahepatic (eCCA), which is further divided into perihilar (pCCA) and distal (dCCA) subtypes, with higher incidence rates in Asia. Despite its rarity, CCA has a low 5-year survival rate and remains the leading cause of primary liver tumor-related death over the past 10-20 years. The systemic therapy section discusses gemcitabine-based regimens as primary treatments, along with oxaliplatin-based options. Second-line therapy is limited but may include short-term infusional fluorouracil (FU) plus leucovorin (LV) and oxaliplatin. The adjuvant therapy section discusses approaches to improve overall survival (OS) post-surgery. However, only a minority of CCA patients qualify for surgical resection. In comparison to adjuvant therapies, neoadjuvant therapy for unresectable cases shows promise. Gemcitabine and cisplatin indicate potential benefits for patients awaiting liver transplantation. The addition of immunotherapies to chemotherapy in combination is discussed. Nivolumab and innovative approaches like CAR-T cells, TRBAs, and oncolytic viruses are explored. We aim in this review to provide a comprehensive report on the systemic and locoregional therapies for CCA.

Practical considerations for pathological diagnosis and molecular profiling of cholangiocarcinoma: an expert review for best practices

INTRODUCTION

Advances in precision medicine have expanded access to targeted therapies and demand for molecular profiling of cholangiocarcinoma (CCA) patients in routine clinical practice. However, pathologists face challenges in establishing a definitive intrahepatic CCA (iCCA) diagnosis while preserving sufficient tissue for molecular profiling. Additionally, they frequently face challenges in optimal tissue handling to preserve nucleic acid integrity.

AREAS COVERED

This article first identifies the challenges in establishing a definitive diagnosis of iCCA in a lesional liver biopsy while preserving sufficient tissue for molecular profiling. Then, the authors explore the clinical value of molecular profiling, the basic principles of single gene and next-generation sequencing (NGS) techniques, and the challenges in tissue sampling for genomic testing. They also propose an algorithm for best practice in tissue management for molecular profiling of CCA.

EXPERT OPINION

Several practical challenges face pathologists during tissue sampling and processing for molecular profiling. Optimized tissue processing, careful tissue handling, and selection of appropriate approaches to molecular testing are essential to ensure that the highest possible quality of diagnostic information is provided in the greatest proportion of cases.

Molecular Profile of Intrahepatic Cholangiocarcinoma

Intrahepatic cholangiocarcinoma (ICC) is a relatively uncommon but highly aggressive primary liver cancer that originates within the liver. The aim of this study is to review the molecular profile of intrahepatic cholangiocarcinoma and its implications for prognostication and decision-making. This comprehensive characterization of ICC tumors sheds light on the disease's underlying biology and offers a foundation for more personalized treatment strategies. This is a narrative review of the prognostic and therapeutic role of the molecular profile of ICC. Knowing the molecular profile of tumors helps determine prognosis and support certain target therapies. The molecular panel in ICC helps to select patients for specific therapies, predict treatment responses, and monitor treatment responses. Precision medicine in ICC can promote improvement in prognosis and reduce unnecessary toxicity and might have a significant role in the management of ICC in the following years. The main mutations in ICC are in tumor protein p53 (TP53), Kirsten rat sarcoma virus (KRAS), isocitrate dehydrogenase 1 (IDH1), and AT-rich interactive domain-containing protein 1A (ARID1A). The rate of mutations varies significantly for each population. Targeting TP53 and KRAS is challenging due to the natural characteristics of these genes. Different stages of clinical studies have shown encouraging results with inhibitors of mutated IDH1 and target therapy for ARID1A downstream effectors. Fibroblast growth factor receptor 2 (FGFR2) fusions are an important target in patients with ICC. Immune checkpoint blockade can be applied to a small percentage of ICC patients. Molecular profiling in ICC represents a groundbreaking approach to understanding and managing this complex liver cancer. As our comprehension of ICC's molecular intricacies continues to expand, so does the potential for offering patients more precise and effective treatments. The integration of molecular profiling into clinical practice signifies the dawn of a new era in ICC care, emphasizing personalized medicine in the ongoing battle against this malignancy.

Clinical experience with pemigatinib for previously treated metastatic cholangiocarcinoma: practical considerations from clinical cases

The management of advanced cholangiocarcinoma (CCA) is challenging. In patients with advanced CCA, gemcitabine/cisplatin combination is the standard frontline chemotherapy, with 5-fluorouracil-based regimens preserved for subsequent lines; however, the expected survival is poor. Pemigatinib was approved for locally advanced or metastatic CCA with FGFR2 fusions or rearrangement. Pemigatinib has a manageable safety profile and achieves a durable response. Nearly 50 patients with CCA have been treated with pemigatinib in the United Kingdom. However, clinical experience with pemigatinib is lacking. We present our experience with three clinical cases to illustrate the position of pemigatinib in the management of CCA and related toxicities.

Evolution of the Targeted Therapy Landscape for Cholangiocarcinoma: Is Cholangiocarcinoma the 'NSCLC' of GI Oncology?

In the past two decades, molecular targeted therapy has revolutionized the treatment landscape of several malignancies. Lethal malignancies such as non-small cell lung cancer (NSCLC) have become a model for precision-matched immune- and gene-targeted therapies. Multiple small subgroups of NSCLC defined by their genomic aberrations are now recognized; remarkably, taken together, almost 70% of NSCLCs now have a druggable anomaly. Cholangiocarcinoma (CCA) is a rare tumor with a poor prognosis. Novel molecular alterations have been recently identified in patients with CCA, and the potential for targeted therapy is being realized. In 2019, a fibroblast growth factor receptor 2 (FGFR2) inhibitor, pemigatinib, was the first approved targeted therapy for patients with locally advanced or metastatic intrahepatic CCA who had FGFR2 gene fusions or rearrangement. More regulatory approvals for matched targeted therapies as second-line or subsequent treatments in advanced CCA followed, including additional drugs that target FGFR2 gene fusion/rearrangement. Recent tumor-agnostic approvals include (but are not limited to) drugs that target mutations/rearrangements in the following genes and are hence applicable to CCA: isocitrate dehydrogenase 1 (IDH1); neurotrophic tropomyosin-receptor kinase (NTRK); the V600E mutation of the BRAF gene (BRAFV600E); and high tumor mutational burden, high microsatellite instability, and gene mismatch repair-deficient (TMB-H/MSI-H/dMMR) tumors. Ongoing trials investigate HER2, RET, and non-BRAFV600E mutations in CCA and improvements in the efficacy and safety of new targeted treatments. This review aims to present the current status of molecularly matched targeted therapy for advanced CCA.

Development and validation of combined Ki67 status prediction model for intrahepatic cholangiocarcinoma based on clinicoradiological features and MRI radiomics

PURPOSE

Incidence and mortality of intrahepatic cholangiocarcinoma (ICC) have been increasing over the past few decades, and Ki67 is an adverse prognostic predictor and an attractive therapeutic target for ICC patients. Thus, we aim to develop and validate a combined Ki67 prediction model for ICC patients.

MATERIALS AND METHODS

Preoperative contrast-enhanced MR images were collected from 178 patients with postoperative pathologically confirmed ICC, and randomly divided into training and validation cohorts in a ratio of 7:3 (124:54). A time-independent test cohort of 49 ICC patients was used for validation. Independent clinicoradiological features of Ki67 status were determined by multivariate analysis. Optimal radiomics features were selected by least absolute shrinkage and selection operator logistic regression and linear discriminant analysis was used to construct combined models. The prediction efficacy of combined model was assessed by receiver operating characteristics curve, and verified by its calibration, decision and clinical impact curves.

RESULTS

HBV (p = 0.022), arterial rim enhancement (p = 0.006) and enhancement pattern (p = 0.012) are independent clinicoradiological features. The radiomics model achieves good prediction efficacy in the training cohort (AUC = 0.860) and validation cohort (AUC = 0.843). The combined Ki67 prediction model incorporates clinicoradiological and radiomics features, and it yields desirable predictive efficiency in test cohort (AUC = 0.815). Decision curves and clinical impact curves further validate that the combined Ki67 prediction model can achieve net benefits in clinical work.

CONCLUSION

The combined Ki67 model incorporating HBV, arterial rim enhancement, enhancement pattern and radiomics features is a potential biomarker in Ki67 prediction and stratification.

Is it safe to administer neoadjuvant chemotherapy to patients undergoing hepatectomy for intrahepatic cholangiocarcinoma? ACS-NSQIP propensity-matched analysis

BACKGROUND

The use of neoadjuvant chemotherapy (NAC) in patients with intrahepatic cholangiocarcinoma (iCCA) is increasing. The objective of this study was to compare the 30-day post-operative complications and length-of-stay (LOS) between patients undergoing hepatectomy for iCCA with and without NAC.

METHODS

A retrospective study was conducted using the ACS-NSQIP database queried from 2014 to 2018. Patients with NAC receipt were propensity-score matched into 1:3 ratio with controls using the greedy-matching algorithm and a caliper of 0.2. Logistic and Poisson regression models were used to estimate the effect sizes.

RESULTS

A total of 1508 patients who underwent hepatectomy for iCCA were included. 706 patients remained after matching and balance were achieved. The NAC group had 110 (60.1%) complications vs. 289 (55.3%) complications in the non-NAC group (p = 0.29). NAC was not associated with worse 30-day postoperative complications [OR 1.24, 95% CI: 0.87-1.76; p = 0.24]. Post-operative LOS in the NAC group was 8.56 days (mean, SD 7.4) vs. non-NAC group 9.27 days (mean, SD 8.41, p = 0.32). NAC was not associated with longer post-operative LOS [RR 0.93, 95% CI:0.80, 1.08; p = 0.32].

CONCLUSION

NAC may be safely administered without increasing the risk of 30-day complications or post-operative hospital LOS.

Co-Clinical Trials: An Innovative Drug Development Platform for Cholangiocarcinoma

Cholangiocarcinoma (CCA), a group of malignancies that originate from the biliary tract, is associated with a high mortality rate and a concerning increase in worldwide incidence. In Thailand, where the incidence of CCA is the highest, the socioeconomic burden is severe. Yet, treatment options are limited, with surgical resection being the only form of treatment with curative intent. The current standard-of-care remains adjuvant and palliative chemotherapy which is ineffective in most patients. The overall survival rate is dismal, even after surgical resection and the tumor heterogeneity further complicates treatment. Together, this makes CCA a significant burden in Southeast Asia. For effective management of CCA, treatment must be tailored to each patient, individually, for which an assortment of targeted therapies must be available. Despite the increasing numbers of clinical studies in CCA, targeted therapy drugs rarely get approved for clinical use. In this review, we discuss the shortcomings of the conventional clinical trial process and propose the implementation of a novel concept, co-clinical trials to expedite drug development for CCA patients. In co-clinical trials, the preclinical studies and clinical trials are conducted simultaneously, thus enabling real-time data integration to accurately stratify and customize treatment for patients, individually. Hence, co-clinical trials are expected to improve the outcomes of clinical trials and consequently, encourage the approval of targeted therapy drugs. The increased availability of targeted therapy drugs for treatment is expected to facilitate the application of precision medicine in CCA.

Neoadjuvant treatment strategies for intrahepatic cholangiocarcinoma

Intrahepatic cholangiocarcinoma (ICC) is the second most common primary liver malignancy and is increasing in incidence. Long-term outcomes are optimized when patients undergo margin-negative resection followed by adjuvant chemotherapy. Unfortunately, a significant proportion of patients present with locally advanced, unresectable disease. Furthermore, recurrence rates are high even among patients who undergo surgical resection. The delivery of systemic and/or liver-directed therapies prior to surgery may increase the proportion of patients who are eligible for surgery and reduce recurrence rates by prioritizing early systemic therapy for this aggressive cancer. Nevertheless, the available evidence for neoadjuvant therapy in ICC is currently limited yet recent advances in liver directed therapies, chemotherapy regimens, and targeted therapies have generated increasing interest its role. In this article, we review the rationale for, current evidence for, and ongoing research efforts in the use of neoadjuvant therapy for ICC.

Targeted deep sequencing contributes to guiding personalized targeted therapy for advanced biliary tract cancer patients with non‑radical resection: A real‑world study

Targeted therapy based on specific genetic alterations has been proven to be an effective treatment for various types of cancer. In the present study, we aimed to explore the efficacy of personalized targeted therapy guided by targeted deep sequencing for patients with advanced biliary tract cancer (BTC) after non-radical resection. Targeted deep sequencing was performed on 49 patients with BTC, to whom biologic agents were recommended. Among 32 patients with stage IV and R2 resection (a non-radical resection), 21 patients underwent conventional chemotherapy (mGEMOX), while the remaining 11 patients received a personalized targeted agent. The genomic landscape of the 49 patients with BTC was determined and the results showed that genetic alterations were enriched in the ERBB family and cell cycle pathway. After a median follow-up of 12 months, the 11 BTC patients with personalized targeted therapy showed a median progression-free survival (PFS) of 4.5 months (2.5–20.5 months), a median overall survival (OS) of 12.9 months (4.7–24.8 months) and a disease control rate (DCR) of 63.6%. In the other 21 BTC patients, who were undergoing conventional chemotherapy, the BTC patients had a median PFS of 1.5 months (0.5–11.6 months), a median OS of 4.1 months (1.3–18.4 months), and a DCR of 33.3%. In addition, 36.4% of the patients in the personalized targeted therapy group experienced grade >2 treatment-related toxicity vs. 19.0% of patients in the conventional chemotherapy group. This real-world study suggests that targeted deep sequencing contributes to the guidance of personalized targeted therapy based on individual actionable mutations, which may benefit advanced BTC patients undergoing non-radical resection.

The diagnostic and prognostic value of UBE2T in intrahepatic cholangiocarcinoma

Background

Ubiquitin-conjugating enzyme E2T (UBE2T) is overexpressed in several types of malignancies. However, little is known about its diagnostic significance in intrahepatic cholangiocarcinoma (ICC) and other bile duct diseases or its prognostic value in ICC.

Methods

The expression levels of UBE2T in the intrahepatic bile duct (IHBD, N = 13), biliary intraepithelial neoplasia (BilIN; BilIN-1/2, N = 23; BilIN-3, N = 11), and ICC (N = 401) were examined by immunohistochemistry. The differential diagnostic and prognostic values were also assessed.

Results

The number of UBE2T-positive cells was significantly higher in ICC tissues than in nonmalignant tissues, including the IHBD, BilIN-1/2, and BilIN-3 tissues. Kaplan–Meier analysis showed that overexpression of UBE2T was correlated with a shorter time to recurrence (TTR) and overall survival (OS). The 5-year TTR rates in the high UBE2T and low UBE2T groups were 100% and 86.2%, respectively. The corresponding OS rates were 1.9% and 22.2%, respectively. High expression of UBE2T was an independent risk factor for both TTR (hazard ratio: 1.345; 95% confidence interval: 1.047,1.728) and OS (hazard ratio: 1.420; 95% confidence interval: 1.098,1.837).

Conclusions

UBE2T can assist in differentiating benign bile duct diseases from ICC, and high expression of UBE2T suggests a poor prognosis for ICC.

Functions of FGFR2 corrupted by translocations in intrahepatic cholangiocarcinoma

Cholangiocarcinoma, originating from the biliary duct, represents a subset of liver cancer. With about 8000 new cases of cholangiocarcinoma diagnosed annually in the U.S., these fall into three categories: intrahepatic, peri-hilar, and extrahepatic cholangiocarcinoma. Arising from the epithelium of the bile duct, intrahepatic cholangiocarcinoma (ICC) is a universally fatal malignancy with very few treatment options. The poor prognosis and lack of molecular targeted therapies highlights ICC as a critical unmet medical need. With advances in sequencing technology, numerous chromosomal translocations have been discovered as drivers in cancer initiation and progression. Particularly in ICC, chromosomal translocations involving Fibroblast Growth Factor Receptor 2 (FGFR2) have been frequently identified, resulting in the creation of oncogenic fusion proteins. At the N-terminus, these fusion proteins share a nearly-identical FGFR2 moiety retaining an intact kinase domain and, at the C-terminus, a dimerization/oligomerization domain provided by different partner genes, including: Periphilin 1 (PPHLN1), Bicaudal family RNA binding protein 1 (BICC1), Adenosylhomocysteinase Like 1 (AHCYL1), and Transforming Acidic Coiled-Coil Containing Protein 3 (TACC3). A number of pre-clinical and clinical trials have shown the effectiveness of FGFR inhibitors in treating FGFR2 fusion-positive ICC patients. However, the efficacy of these inhibitors may be short-lived due to acquired resistance. In this review, we provide an overview of FGFR2 fusions, comparing their structures and mechanism of dimerization, examining the importance of FGFR2 as a partner gene, as well as highlighting the significance of alternative splicing of FGFR2 in these fusion proteins. In addition, we discuss various therapeutic options and their associated potencies in targeting these translocation-induced ICCs.

BAP1 in solid tumors

One of the most attractive cancer-related genes under investigation is BAP1. Reasons of this growing interest are related to the wide spectrum of pathways directly or indirectly modulated by this gene and shared by several solid tumors. Programmed cell-death, cell metabolisms, immune cells development, ferroptosis and defects in DNA damage response are only some of the multitude of processes depending on BAP1. Loss of this gene seems to occur in different times of tumor history. Moreover, times of BAP1 loss strongly diverge among primary tumors suggesting the presence of several and different triggering factors. Regardless of when it happens, BAP1 loss usually results in prognosis worsening and in the acquisition of more aggressive clinical features by cancer cells.

Bile cell‑free DNA as a novel and powerful liquid biopsy for detecting somatic variants in biliary tract cancer

Tissue sampling of biliary tract carcinomas (BTCs) for molecular characterization is challenging. The aim of this study was to investigate the possibility of identifying individual actionable mutations derived from bile cell-free DNA (cfDNA) using targeted deep sequencing. Ten BTC patients, four with gallbladder carcinomas and six with cholangiocarcinomas, were enrolled in the present study. Using targeted deep sequencing with a panel of 150 tumor-related genes, paired bile cfDNA and tumor DNA were analyzed for mutational variants individually and then compared. The present study, to the best of our knowledge, is the first to reveal that bile cfDNA is predominantly comprised of long DNA fragments, which is not the case for plasma cfDNA. Herein, paired bile cfDNA and tumors from ten BTC patients were examined using targeted deep sequencing. When comparing bile cfDNA and tumor DNA for single nucleotide variation (SNV)/insertion and deletion (Indel), the results using targeted deep sequencing revealed high sensitivity (94.7%) and specificity (99.9%). Additionally, the sensitivity of detecting a copy number variation (CNV) was 75.0%, with a specificity of 98.9%. When comparing two bile extraction methods, including percutaneous transhepatic cholangial drainage and operation, no significant difference in SNV/Indel or CNV detection sensitivity was noted. Moreover, when examining the tumor stage and incidence site, AJCC stage II and the distal bile duct both had significantly decreased CNV detection sensitivities. The present study revealed that targeted deep sequencing can reliably detect mutational variants within bile cfDNA obtained from BTC patients. These preliminary results may shed light on bile cfDNA as a promising liquid biopsy for BTC patients.

Targeted Therapies in Cholangiocarcinoma: Emerging Evidence from Clinical Trials

Cholangiocarcinoma (CCA) is a highly-aggressive malignancy arising from the biliary tree, characterized by a steady increase in incidence globally and a high mortality rate. Most CCAs are diagnosed in the advanced and metastatic phases of the disease, due to the paucity of signs and symptoms in the early stages. This fact, along with the poor results of the local and systemic therapies currently employed, is responsible for the poor outcome of CCA patients and strongly supports the need for novel therapeutic agents and strategies. In recent years, the introduction of next-generation sequencing technologies has opened new horizons for a better understanding of the genetic pathophysiology of CCA and, consequently, for the identification and evaluation of new treatments tailored to the molecular features or alterations progressively elucidated. In this review article, we describe the potential targets under investigation and the current molecular therapies employed in biliary tract cancers. In addition, we summarize the main drugs against CCA under evaluation in ongoing trials and describe the preliminary data coming from these pioneering studies.

Animal models of cholangiocarcinoma: What they teach us about the human disease

Despite recent advances, pathogenesis of cholangiocarcinoma, a highly lethal cancer, remains enigmatic. Furthermore, treatment options are still limited and often disappointing. For this reason, in the last few years there has been a mounting interest towards the generation of experimental models able to reproduce the main features associated with this aggressive behavior. Toxic and infestation-induced, genetically engineered and cell implantation rodent models have been generated, contributing to a deeper understanding of the complex cell biology of the tumor, sustained by multiple cell interactions and driven by a huge variety of molecular perturbations. Herein, we will overview the most relevant animal models of biliary carcinogenesis, highlighting the methodological strategy, the molecular, histological and clinical phenotypes consistent with the human condition, their particular strengths and weaknesses and the novel therapeutic approaches that have been developed.

Characterization and prognostic significance of mortalin, Bcl-2 and Bax in intrahepatic cholangiocarcinoma

Intrahepatic cholangiocarcinoma (ICC) is an aggressive type of cancer, and its incidence and mortality rates are increasing worldwide. Mortalin is a highly conserved chaperone protein involved in multiple pathological and physiological processes, including anti-apoptosis, carcinogenesis and metastasis. The Bcl-2 family of proteins can be divided into pro-survival and pro-apoptotic members, including B-cell lymphoma 2 (Bcl-2) and Bcl-2-like protein 4 (Bax). The aim of the present study was to investigate the association between mortalin, Bcl-2 and Bax, as well as the prognostic significance of the combined expression of mortalin, Bcl-2 and Bax in ICC. Immunohistochemistry was used to determine the expression of mortalin, Bcl-2 and Bax in 116 ICC samples and to assess the association between expression of 3 markers and clinicopathological features of ICC patients. This revealed that ICC tumor tissues overexpressed mortalin and Bcl-2 and exhibited low expression of Bax in ICC tumor tissues compared with that in corresponding peritumoral samples. According to Pearson's correlation coefficient analysis, high expression of mortalin in ICC was positively correlated with Bcl-2 expression and negatively correlated with Bax expression. Furthermore, multiple linear regression analysis demonstrated that mortalin was positively associated with Bcl-2, but not with Bax, in patients with ICC. Patients with ICC exhibiting high expression of mortalin/Bcl-2 or low expression of Bax were closely associated with a malignant ICC phenotype, a relatively low overall survival rate and a high recurrence rate. Multivariate analysis indicated that mortalin and Bcl-2 were independent prognostic indicators for ICC patients. Meanwhile, the concomitant overexpression of mortalin and Bcl-2 and the low expression of Bax were independent markers for predicting a relatively poor prognosis of ICC. The overexpression of mortalin and Bcl-2 and/or the low expression of Bax are implicated in the anti-apoptotic effect and tumor progression of ICC. Mortalin or Bcl-2, or a combination of mortalin, Bcl-2 and Bax may be used to predict the prognosis of ICC, as well as potential therapeutic targets.

New insights into cholangiocarcinoma: multiple stems and related cell lineages of origin

Cholangiocarcinoma (CCA) is a heterogeneous group of malignancies that may develop at any level of the biliary tree. CCA is currently classified into intrahepatic (iCCA), perihilar (pCCA) and distal (dCCA) on the basis of its anatomical location. Notably, although these three CCA subtypes have common features, they also have important inter- and intra-tumor differences that can affect their pathogenesis and outcome. A unique feature of CCA is that it manifests in the hepatic parenchyma or large intrahepatic and extrahepatic bile ducts, furnished by two distinct stem cell niches: the canals of Hering and the peribiliary glands, respectively. The complexity of CCA pathogenesis highlights the need for a multidisciplinary, translational, and systemic approach to this malignancy. This review focuses on advances in the knowledge of CCA histomorphology, risk factors, molecular pathogenesis, and subsets of CCA.