Efficacy and biomarker analysis of nivolumab plus gemcitabine and cisplatin in patients with unresectable or metastatic biliary tract cancers: results from a phase II study

Intrahepatic cholangiocarcinoma: tumour heterogeneity and its clinical relevance

Treatment of intrahepatic cholangiocarcinoma (iCCA) is currently at a significant turning point due to the identification of isocitrate dehydrogenase (IDH) mutations and fibroblast growth factor receptor (FGFR) fusions that can be targeted with currently available therapies. Clinical trials of these targeted therapies have been promising, and the iCCA patients who may benefit from these targeted treatments can be identified by pathological examination prior to molecular investigations. This is because IDH mutations and FGFR fusions are mainly seen in the small duct type iCCA, a subtype of iCCA defined by the 5th World Health Organization classification, which can be recognized by the pathological diagnostic process. Therefore, pathology plays an important role in precision medicine for iCCA, not only in confirming the diagnosis, but also in identifying the iCCA patients who may benefit from targeted treatments. However, caution is advised with the pathological diagnosis, as iCCA shows tumour heterogeneity, making it difficult to distinguish small duct type iCCA from hepatocellular carcinoma (HCC), and combined HCC-CCA. This review focuses on the pathological/molecular features of both subtypes of iCCA (large and small duct types), as well as their diagnostic pitfalls, clinical relevance, and future perspectives.

Immunotherapy for Biliary Tract Cancer in the Era of Precision Medicine: Current Knowledge and Future Perspectives

Biliary tract cancers (BTC) represent a heterogeneous and aggressive group of tumors with dismal prognosis. For a long time, BTC has been considered an orphan disease with very limited therapeutic options. In recent years a better understanding of the complex molecular landscape of biology is rapidly changing the therapeutic armamentarium. However, while 40-50% of patients there are molecular drivers susceptible to target therapy, for the remaining population new therapeutic options represent an unsatisfied clinical need. The role of immunotherapy in the continuum of treatment of patients with BTC is still debated. Despite initial signs of antitumor-activity, single-agent immune checkpoint inhibitors (ICIs) demonstrated limited efficacy in an unselected population. Therefore, identifying the best partner to combine ICIs and predictive biomarkers represents a key challenge to optimize the efficacy of immunotherapy. This review provides a critical analysis of completed trials, with an eye on future perspectives and possible biomarkers of response.

Treatment of Intrahepatic Cholangiocarcinoma-A Multidisciplinary Approach

Simple Summary

This review discusses multimodality treatment strategies for intrahepatic cholangiocarcinoma (iCC). Surgical resection remains the only potentially curative therapeutic option and the central cornerstone of treatment. Adjuvant systemic treatment will be recommended after resection or in the palliative setting. Increasing knowledge of phenotypic subclassification and molecular profiling allows investigation of targeted therapies as (neo-)adjuvant treatment. High-dose brachytherapy, internal radiation therapy, and transarterial chemoembolization are among the interventional treatment options being evaluated for unresectable iCC. Given the multiple options of multidisciplinary management, any treatment strategy should be discussed in a multidisciplinary tumor board and treatment should be directed by a specialized treatment center.

Abstract

Intrahepatic cholangiocarcinoma (iCC) is distinguished as an entity from perihilar and distal cholangiocarcinoma and gallbladder carcinoma. Recently, molecular profiling and histopathological features have allowed further classification. Due to the frequent delay in diagnosis, the prognosis for iCC remains poor despite major technical advances and multimodal therapeutic approaches. Liver resection represents the therapeutic backbone and only curative treatment option, with the functional residual capacity of the liver and oncologic radicality being deciding factors for postoperative and long-term oncological outcome. Furthermore, in selected cases and depending on national guidelines, liver transplantation may be a therapeutic option. Given the often advanced tumor stage at diagnosis or the potential for postoperative recurrence, locoregional therapies have become increasingly important. These strategies range from radiofrequency ablation to transarterial chemoembolization to selective internal radiation therapy and can be used in combination with liver resection. In addition, adjuvant and neoadjuvant chemotherapies as well as targeted therapies and immunotherapies based on molecular profiles can be applied. This review discusses multimodal treatment strategies for iCC and their differential use.

PD-1 Inhibitors Plus Capecitabine as Maintenance Therapy for Advanced Intrahepatic Cholangiocarcinoma: A Case Report and Review of Literature

Intrahepatic cholangiocarcinoma (iCCA) is the second most common primary liver cancer with a poor prognosis. Recently, an immunotherapy strategy represented by programmed cell death 1 (PD-1) inhibitors has been applied to the systemic treatment of advanced iCCA. However, immunotherapy combined with chemotherapy as first-line maintenance therapy was rarely reported. Our report presented an advanced iCCA patient who had a dramatic response to the PD-1 inhibitor sintilimab combined with gemcitabine plus cisplatin as the first-line therapy and sintilimab combined with capecitabine as maintenance therapy, yielding an ongoing progression-free survival of 16 months.

Combination therapy with immune checkpoint inhibitors (ICIs); a new frontier

Recently, immune checkpoint inhibitors (ICIs) therapy has become a promising therapeutic strategy with encouraging therapeutic outcomes due to their durable anti-tumor effects. Though, tumor inherent or acquired resistance to ICIs accompanied with treatment-related toxicities hamper their clinical utility. Overall, about 60-70% of patients (e.g., melanoma and lung cancer) who received ICIs show no objective response to intervention. The resistance to ICIs mainly caused by alterations in the tumor microenvironment (TME), which in turn, supports angiogenesis and also blocks immune cell antitumor activities, facilitating tumor cells' evasion from host immunosurveillance. Thereby, it has been supposed and also validated that combination therapy with ICIs and other therapeutic means, ranging from chemoradiotherapy to targeted therapies as well as cancer vaccines, can capably compromise tumor resistance to immune checkpoint blocked therapy. Herein, we have focused on the therapeutic benefits of ICIs as a groundbreaking approach in the context of tumor immunotherapy and also deliver an overview concerning the therapeutic influences of the addition of ICIs to other modalities to circumvent tumor resistance to ICIs.

Case Report: Response With Immunotherapy in a Patient With Mixed Neuroendocrine Non-Neuroendocrine Neoplasms of the Gallbladder

Background

Primary neuroendocrine tumors of the gallbladder (GB-NETs) are rare, accounting for 2% of all gallbladder cancers. Among GB-NETs, mixed neuroendocrine non-neuroendocrine neoplasms of the gallbladder (GB-MiNENs) are sporadic.

Case Presentation

A 56-year-old woman admitted to our hospital due to right upper abdominal pain of 3 days duration. She underwent positron emission tomography/computed tomography, which showed multiple metastatic tumors and was unsuitable for operation. Initially, the patient was diagnosed with gallbladder adenocarcinoma. She underwent PD-1 inhibitor or combined with chemotherapy considering the PD-L1 high positive score. In the latter, the patient has the opportunity of surgery, and the new diagnosis was MiNENs. She achieved long-term disease control and has been alive from the first diagnosis.

Conclusion

This case might support the strategy that PD-1 inhibitor could provide a feasible treatment option for MiNENs of gallbladder patients with the positive expression of PD-L1 in the future.

Cholangiocarcinoma: new perspectives for new horizons

INTRODUCTION

Biliary tract cancer represents a heterogeneous group of malignancies characterized by dismal prognosis and scarce therapeutic options.

AREA COVERED

In the last years, a growing interest in BTC pathology has emerged, thus highlighting a significant heterogeneity of the pathways underlying the carcinogenesis process, from both a molecular and genomic point of view. A better understanding of these differences is mandatory to deepen the behavior of this complex disease, as well as to identify new targetable target mutations, with the aim to improve the survival outcomes. The authors decided to provide a comprehensive overview of the recent highlights on BTCs, with a special focus on the genetic, epigenetic and molecular alterations, which may have an interesting clinical application in the next future.

EXPERT OPINION

In the last years, the efforts resulted from international collaborations have led to the identification of new promising targets for precision medicine approaches in the BTC setting. Further investigations and prospective trials are needed, but the hope is that these new knowledge in cooperation with the new technologies and procedures, including bio-molecular and genomic analysis as well radiomic studies, will enrich the therapeutic armamentarium thus improving the survival outcomes in a such lethal and complex disease.

Immune Checkpoint Inhibitors: The Emerging Cornerstone in Cholangiocarcinoma Therapy?

BACKGROUND

Cholangiocarcinoma (CCA) encompasses a heterogeneous group of malignant tumors with dismal prognosis and increasing incidence worldwide. Both late diagnosis due to the lack of early symptoms and the refractory nature of these tumors seriously compromise patients' welfare and outcomes.

SUMMARY

During the last decade, immunotherapy and, more specifically, modulation of immune checkpoints-mediated signaling pathways have been under the spotlight in the field of oncology, emerging as a potential therapeutic approach for the treatment of several cancers, including CCA. Generally, high expression levels of immune checkpoints in patients with CCA have been associated with worse clinical outcomes, particularly with shorter overall survival and relapse-free survival. Thus, immune checkpoint inhibitors (ICIs), which mainly constitute different monoclonal antibodies, have been developed in order to hamper the immune checkpoint-mediated pathways. Interestingly, chemotherapy may increase the expression of immune checkpoints, while other therapeutic approaches such as ablative and targeted therapies may enhance their antitumor activity. In this sense, several clinical trials evaluated the safety and efficacy of ICIs for CCA, both as a monotherapy and in combination with other ICIs or loco-regional and systemic therapies. Additionally, many other clinical trials are currently ongoing and results are eagerly awaited. Here, we summarize the key aspects of immune checkpoint molecules as prognostic factors and therapeutic targets in CCA, highlighting the most recent advances in the field and future research directions.

KEY MESSAGES

(1) Effective therapeutic approaches for CCA are urgently needed. (2) Expression levels of immune checkpoints in patients with CCA have been proposed to be related with clinical outcomes. (3) Combination of different ICIs may outperform the efficacy of ICI monotherapy for CCA treatment. (4) Recent studies point toward the combination of ICIs and other common therapies, especially chemotherapy, as a promising strategy for treatment of CCA patients.

Efficacy of Immune Checkpoint Inhibitors in Rare Tumours: A Systematic Review

Background

Rare cancers, as defined by the European Union, occur in fewer than 15 out of 100,000 people each year. The International Rare Cancer Consortium defines rare cancer incidence as less than six per 100,000 per year. There is a growing number of reports of the efficacy of immune checkpoint inhibitor (ICI) therapy in patients with rare tumours, and hence, we conducted a comprehensive review to summarise and analyse the available literature.

Methods

A literature search of PubMed was performed on January 31, 2021, using the following ICI names as keywords: ipilimumab, tremelimumab, cemiplimab, nivolumab, pembrolizumab, avelumab, atezolizumab, and durvalumab. Studies on patients with rare tumours who were being treated with ICIs were included. We plotted the overall response rate against the corresponding median survival across a variety of cancer types using linear regression.

Results

From 1,255 publications retrieved during the primary search, 62 publications were selected (with a total of 4,620 patients). Only four were randomised trials. A minority were first-line studies, while the remaining were studies in which ICIs were delivered as salvage therapy in pretreated patients. There was a good correlation between response rate and overall survival (Spearman R2 >0.9) in skin cancers, mesothelioma, and sarcomas.

Conclusions

Treatment of advanced-stage rare tumours with ICI therapy was found to be associated with significant activity in some orphan diseases (e.g., Merkel cell carcinoma) and hepatocellular carcinoma. Several ongoing prospective clinical trials will expand the knowledge on the safety and efficacy of ICI therapy in patients with these rare cancers.

Atezolizumab: an investigational agent for the treatment of biliary tract cancer

INTRODUCTION

Biliary tract cancers (BTCs) have a dismal prognosis and limited treatment options. The role of immunotherapy in BTC is unclear. BTCs respond poorly to PD-(L)1 blockade, highlighting the need for combination regimens to augment antitumor immunity. Atezolizumab (anti-PD-L1) combined with other therapies is under investigation in advanced BTC.

AREAS COVERED

This paper provides an overview of the recent progress and future applications of immunotherapy for BTCs and sheds light on the status and therapeutic potential of atezolizumab. We discuss published data for atezolizumab and an examine the rationale and design of ongoing clinical studies. We offer insights and opinions on the future applications and challenges of immunotherapy in BTC.

EXPERT OPINION

Atezolizumab monotherapy has demonstrated limited antitumor activity in BTC, indicating the need for combination regimens to unlock effective anticancer immunity, and the development of predictive biomarkers to enrich the population. Data for atezolizumab combined with chemotherapy, anti-VEGF agents and other targeted drugs in solid tumors justifies their evaluation in BTC. Several novel atezolizumab-based combinations have been or are currently under investigation in Phase II studies. It is hoped that data from these studies, along with other immunotherapy trials, will provide more effective treatments for patients with BTC.

Challenges for Better Diagnosis and Management of Pancreatic and Biliary Tract Cancers Focusing on Blood Biomarkers: A Systematic Review

Simple Summary

Pancreatic and biliary tract cancers are malignant tumors that have a very poor prognosis and are resistant to chemotherapy. The later a cancer is detected, the worse the prognosis becomes; therefore, early detection is important. Biomarkers are physiological indices that serve as a guide to indicate the presence or absence of a certain disease, or its progression. The purpose of our research is to summarize previously reported biomarkers for the diagnosis and prognosis of pancreatic and biliary tract cancers.

Abstract

Background: pancreatic cancer (PCa) and biliary tract cancer (BTC) are cancers with a poor prognosis and few effective treatments. One of the reasons for this is late detection. Many researchers are tackling to develop non-invasive biomarkers for cancer, but few are specific for PCa or BTC. In addition, genetic abnormalities occur in cancer tissues, which ultimately affect the expression of various molecules. Therefore, it is important to identify molecules that are altered in PCa and BTC. For this systematic review, a systematic review of Medline and Embase to select biomarker studies of PCa and BTC patients was conducted. Results: after reviewing 72 studies, 79 biomarker candidates were identified, including 22 nucleic acids, 43 proteins, and 14 immune cell types. Of the 72 studies, 61 examined PCa, and 11 examined BTC. Conclusion: PCa and BTC are characterized by nucleic acid, protein, and immune cell profiles that are markedly different from those of healthy subjects. These altered molecules and cell subsets may serve as cancer-specific biomarkers, particularly in blood. Further studies are needed to better understand the diagnosis and prognosis of PCa and BTC.

IMbrave 151: a randomized phase II trial of atezolizumab combined with bevacizumab and chemotherapy in patients with advanced biliary tract cancer

Background:

Biliary tract cancers (BTCs) are heterogenous, highly aggressive tumors that harbor a dismal prognosis for which more effective treatments are needed. The role of cancer immunotherapy in BTC remains to be characterized. The tumor microenvironment (TME) of BTC is highly immunosuppressed and combination treatments are needed to promote effective anticancer immunity. Vascular endothelial growth factor (VEGF) drives immunosuppression in the TME by disrupting antigen presentation, limiting T-cell infiltration, or potentiating immune-suppressive cells. Many VEGF-regulated mechanisms are thought to be relevant to repressed antitumor immunity in BTC, making dual targeting of VEGF and programmed cell death protein 1 (PD-1)/PD-L1 pathways a rational approach. Gemcitabine and Cisplatin (Gem/Cis) can also modulate anticancer immunity through overlapping and complementary mechanisms to those regulated by VEGF. Anti-PD-L1/VEGF inhibition, coupled with chemotherapy, may potentiate antitumor immunity leading to enhanced clinical benefit.

Methods:

IMbrave 151 is a randomized, double-blind, placebo-controlled, multicenter, international phase II study to evaluate atezolizumab (a PD-L1 inhibitor) in combination with chemotherapy (gemcitabine and cisplatin) and bevacizumab (an anti-VEGF monoclonal antibody) as a first-line treatment for advanced BTC. Approximately 150 patients with previously untreated, advanced BTC will be randomized to either Arm A (atezolizumab + bevacizumab + Gem/Cis) or Arm B (atezolizumab + placebo + Gem/Cis). Randomization is stratified by the presence of metastatic disease, primary tumor location, and geographic region. The primary efficacy endpoint is investigator-assessed progression-free survival (PFS) per RECIST 1.1. Secondary endpoints include objective response rate (ORR), duration of response (DoR), disease control rate (DCR), overall survival (OS), and safety and patient reported outcomes (PROs). Tissue, blood, and stool samples will be collected at baseline and on-treatment in order to perform correlative biomarker analyses.

Discussion:

IMbrave 151 represents the first randomized study to evaluate combined PD-L1/VEGF blockade on a chemotherapy backbone in BTC.

Trial registration:

NCT identifier: NCT04677504; EUDRACT number: 2020-003759-14

Significant Response to Camrelizumab Plus Targeted Drugs in Recurrent Intrahepatic Cholangiocarcinoma: a Case Report and Literature Review

Purpose

Intrahepatic cholangiocarcinoma is the second most common primary liver cancer, and is associated with a poor prognosis and rising incidence rate.

Methods

Here, we reported the case of a middle-aged Asian male who presented with a 9.5-cm liver lesion and was diagnosed with intrahepatic cholangiocarcinoma.

Results

The patient experienced recurrence three times, twice following radical resection and standard adjuvant chemotherapy and once following camrelizumab plus apatinib, after which the tumor progressed with elevated CA 19.9 level. After tissue biopsy for next-generation sequencing, apatinib was replaced by lenvatinib, and the patient achieved disease control again, with a progression-free survival of 10 months.

Conclusion

Combined immunotherapy and targeted therapy regimens are a promising approach for refractory intrahepatic cholangiocarcinoma. Further well-designed prospective clinical trials are needed to confirm the efficacy and safety. Since intrahepatic cholangiocarcinoma is characterized by high heterogeneity and with complex crosstalk among oncogenic pathways, further exploration is required to more deeply understand the mechanism of action of this treatment approach and guide individualized treatment selection.

Chemotherapy for Biliary Tract Cancer in 2021

Biliary tract cancer refers to a group of malignancies including cholangiocarcinoma, gallbladder cancer, and ampullary cancer. While surgical resection is considered the only curative treatment, postoperative recurrence can sometimes occur. Adjuvant chemotherapy is used to prolong prognosis in some cases. Many unresectable cases are also treated with chemotherapy. Therefore, systemic chemotherapy is widely introduced for the treatment of biliary tract cancer. Evidence on chemotherapy for biliary tract cancer is recently on the increase. Combination chemotherapy with gemcitabine and cisplatin is currently the standard of care for first-line chemotherapy in advanced cases. Recently, FOLFOX also demonstrated efficacy as a second-line treatment. In addition, efficacies of isocitrate dehydrogenase inhibitors and fibroblast growth factor receptor inhibitors have been shown. In the adjuvant setting, capecitabine monotherapy has become the standard of care in Western countries. In addition to conventional cytotoxic agents, molecular-targeted agents and immunotherapy have been evaluated in multiple clinical trials. Genetic testing is used to check for genetic alterations and molecular-targeted agents and immunotherapy are introduced based on tumor characteristics. In this article, we review the latest evidence of chemotherapy for biliary tract cancer.

Immunotherapy for cholangiocarcinoma: a 2021 update

Cholangiocarcinoma (CCA) is a rare malignancy with generally dismal prognosis. Immunotherapy has revolutionized the management of cancer patients during the last decade, offering durable responses with an acceptable safety profile, but there are still no significant advances regarding CCA. Novel immunotherapeutic methods, such as cancer vaccines, oncolytic viruses, adoptive cell therapy and combinations of immune checkpoint inhibitors with other agents are currently under investigation and may improve prognosis. Efforts to find robust biomarkers for response are also ongoing. In this review, we discuss the rationale for the use of immunotherapy in CCA and available clinical data. Ongoing trials will also be presented, as well as key findings from each study.

Novel Pharmacological Options in the Treatment of Cholangiocarcinoma: Mechanisms of Resistance

Simple Summary

Cholangiocarcinoma, a tumor derived from epithelial cells of the biliary tree, is characterized by a dismal prognosis. Its late diagnosis, which makes surgical resection not an option for most patients, and its marked refractoriness to standard chemotherapy, justify its high position in the rank of the most lethal cancers. Identifying specific druggable genetic alterations constitutes a promising alternative for the use of personalized targeted anticancer agents, and immunotherapy, or drugs able to interact with proteins involved in the crosstalk between cancer and immune cells, could also be an option in the future. However, it has also been observed that some patients fail to respond to these new therapies or after an initial response, the disease progresses. Therefore, understanding the mechanisms of pharmacoresistance is of utmost importance to design more effective treatments.

Abstract

Despite the crucial advances in understanding the biology of cholangiocarcinoma (CCA) achieved during the last decade, very little of this knowledge has been translated into clinical practice. Thus, CCA prognosis is among the most dismal of solid tumors. The reason is the frequent late diagnosis of this form of cancer, which makes surgical removal of the tumor impossible, together with the poor response to standard chemotherapy and targeted therapy with inhibitors of tyrosine kinase receptors. The discovery of genetic alterations with an impact on the malignant characteristics of CCA, such as proliferation, invasiveness, and the ability to generate metastases, has led to envisage to treat these patients with selective inhibitors of mutated proteins. Moreover, the hope of developing new tools to improve the dismal outcome of patients with advanced CCA also includes the use of small molecules and antibodies able to interact with proteins involved in the crosstalk between cancer and immune cells with the aim of enhancing the immune system’s attack against the tumor. The lack of effect of these new therapies in some patients with CCA is associated with the ability of tumor cells to continuously adapt to the pharmacological pressure by developing different mechanisms of resistance. However, the available information about these mechanisms for the new drugs and how they evolve is still limited.

Beyond Tumor Mutation Burden: Tumor Neoantigen Burden as a Biomarker for Immunotherapy and Other Types of Therapy

Immunotherapy has significantly improved the clinical outcome of patients with cancer. However, the immune response rate varies greatly, possibly due to lack of effective biomarkers that can be used to distinguish responders from non-responders. Recently, clinical studies have associated high tumor neoantigen burden (TNB) with improved outcomes in patients treated with immunotherapy. Therefore, TNB has emerged as a biomarker for immunotherapy and other types of therapy. In the present review, the potential application of TNB as a biomarker was evaluated. The methods of neoantigen prediction were summarized and the mechanisms involved in TNB were investigated. The impact of high TNB and increased number of infiltrating immune cells on the efficacy of immunotherapy was also addressed. Finally, the future challenges of TNB were discussed.

A Perspective on Cell Therapy and Cancer Vaccine in Biliary Tract Cancers (BTCs)

Biliary tract cancer (BTC) is a rare, but aggressive, disease that comprises of gallbladder carcinoma, intrahepatic cholangiocarcinoma and extrahepatic cholangiocarcinoma, with heterogeneous molecular profiles. Advanced disease has limited therapeutic options beyond first-line platinum-based chemotherapy. Immunotherapy has emerged as a viable option for many cancers with a similar unmet need. Therefore, we reviewed current understanding of the tumor immune microenvironment and recent advances in cellular immunotherapy and therapeutic cancer vaccines against BTC. We illustrated the efficacy of dendritic cell vaccination in one patient with advanced, chemorefractory, melanoma-associated antigen (MAGE)-positive gallbladder carcinoma, who was given multiple injections of an allogenic MAGE antigen-positive melanoma cell lysate (MCL)-based autologous dendritic cell vaccine combined with sequential anti-angiogenic therapy. This resulted in good radiological and tumor marker response and an overall survival of 3 years from diagnosis. We postulate the potential synergism of adding anti-angiogenic therapy, such as bevacizumab, to immunotherapy in BTC, as a rational scientific principle to positively modulate the tumor microenvironment to augment antitumor immunity.

Latest evidence on immunotherapy for cholangiocarcinoma

Cholangiocarcinoma (CCA) is a type of aggressive tumor that involves the intrahepatic, perihilar and distal biliary tree, and is usually diagnosed at an advanced stage. The standard first-line systemic therapy for patients with advanced CCA is a combination of gemcitabine and cisplatin; targeted therapies and angiogenesis inhibitors are not widely used clinically at present. However, with the development of precision medicine, immunotherapy has started to play a more important role. Programmed cell death protein 1 inhibitors are now considered a good therapeutic option for CCA. Treatments using chimeric antigen receptor T cells, bispecific antibodies, oncolytic viruses and cancer vaccines have also achieved satisfactory results. In addition, combinations of immunotherapy with a variety of conventional therapies have shown some efficacy, and several studies have provided insights into their use in antitumor therapy. Although there are numerous challenges in the treatment of advanced CCA, immunotherapy remains a noteworthy breakthrough. The current evidence on the immunotherapy of CCA is discussed in the present review.

Integrative clinical and molecular analysis of advanced biliary tract cancers on immune checkpoint blockade reveals potential markers of response

BACKGROUND

While there have been encouraging preliminary clinical results for immune checkpoint inhibitors (ICIs) in BTCs, it remains a challenge to identify the subset of patients who may benefit. In this study, we evaluated the efficacy of ICI treatment in patients with advanced BTCs, and explored potential biomarkers that are predictive of response.

METHODS

The study enrolled 26 patients with advanced microsatellite stable BTCs (15 with gallbladder cancers [GCs] and 11 with intrahepatic cholangiocarcinoma [ICCs]) who received ICI treatment. Targeted next-generation sequencing (NGS) was performed on tumor tissue samples collected from 17 patients. Clinical and genomic characteristics were assessed for the correlation with clinical outcome.

RESULTS

Analysis of the baseline clinical characteristics showed that performance score (PS) of 0 was associated with a better prognosis than PS of 1 (HR = 1.08 × 109 ; 95% CI, 0∼Inf; P = .002). No significant correlations were found between clinical outcome and inflammation-related indicators. NGS profiling of the available tumor tissues, revealed largely non-overlapping somatic alterations between GCs and ICCs. Mutations in LRP1B (HR = 0.26; 95% CI, 0.06-1.21; P = .067), ERBB2 (HR = 0.15; 95% CI, 0.02-1.19; P = .04), or PKHD1 (HR < 0.01; 95% CI, 0-Inf; P = .04) showed strong association with increased progression-free survival (PFS) benefit. Subsequent analysis showed that alterations in the RTK-RAS pathway were associated with improved outcomes (HR = 0.12; 95% CI, 0.02-0.63; P = .003). Tumor mutation burden (TMB) was higher in patients with GC than those with ICC, and was associated with LRP1B mutations (P = .032). We found that patients with 19q amplification (19q Amp) and 9p deletion (9p Del) had poor PFS outcome (19q Amp, HR = 15.4; 95% CI, 2.7-88.5; P < .001; 9p Del; HR = 4.88 × 109 ; 95% CI, 0-Inf; P < .001), while those with chromosomal instability derived PFS benefit (HR = 0.24; 95% CI, 0.05-1.17; P = .057).

CONCLUSION

Our study identified several potential clinical and genomic features that may serve as biomarkers of clinical response to ICIs in advanced BTCs patients. A larger sample size is required for further verification.