Molecular profiling of biliary tract cancer: a target rich disease

Molecular profiling of biliary cancers reveals distinct molecular alterations and potential therapeutic targets

Background

Biliary tract cancers (BTCs) are a heterogeneous group of aggressive, rare malignancies with limited standard chemotherapeutic options for advanced disease. Recent studies have demonstrated potential novel biliary cancer targets and a possible role for immunotherapy in the treatment of patients with this disease. Intrahepatic cholangiocarcinoma (IHCC), extrahepatic cholangiocarcinoma (EHCC), and gallbladder carcinoma (GBC) are frequently grouped together in clinical trials despite differences in tumor biology.

Methods

To further investigate tumor biology differences, we profiled 1,502 BTCs using next-generation sequencing (NGS), immunohistochemistry, in situ hybridization, and RNA sequencing.

Results

IHCCs had higher rates of IDH1, BAP1, and PBRM1 mutations and FGFR2 fusions; EHCCs had higher rates of KRAS, CDKN2A, and BRCA1 mutations; and GBCs had higher rates of homologous recombination repair deficiency and Her2/neu overexpression and amplification. IHCCs and GBCs had higher rates of potential positive predictive biomarkers for immune checkpoint inhibition (PD-L1 expression, high microsatellite instability, and high tumor mutational burden) than EHCCs.

Conclusions

These findings support clinical molecular profiling of BTCs to inform potential therapeutic selection and clinical trial design based on the primary tumor's site of origin within the biliary tree.

Systemic therapy for gallbladder cancer

Gallbladder cancer is an aggressive cancer that continues to be an important health care issue in certain regions of the world such as Southeast Asia and Latin America. Most patients are diagnosed at an advanced, unresectable stage and systemic therapy is their only option. Gallbladder cancer patients have traditionally been included in clinical trials for biliary tract cancer. Thus, systemic chemotherapy options for this cancer are similar to those for cholangiocarcinoma, including gemcitabine and cisplatin in the first line and FOLFOX in the second-line setting. Ongoing phase III clinical trials may change the systemic therapy paradigm for this cancer. Molecular profiling has indicated important genetic differences between gallbladder cancer and cholangio-carcinoma, which affects choice of targeted therapy. Her2/neu amplification, PIK3CA mutations and DNA repair genetic aberrations are relatively frequent and represent actionable targets for this cancer.

Molecular perturbations in cholangiocarcinoma: Is it time for precision medicine?

The complexity of cholangiocarcinoma (CCA) cellularity and the molecular perturbation mechanisms that underlie the diversity of growth patterns of this malignancy remain a clinical concern. Tumours of the biliary system display significant intrinsic chemoresistance, caused by significant stromal involvement and genome-wide tumour heterogeneity, hampering disease remission and palliation as well as promoting the metastatic behaviour. It is crucial to advance our present understanding of the risk and molecular pathogenesis of CCA. This will facilitate the delineation of patient subsets based on molecular perturbations and adjust for precision therapies.

Assessment of a High Sensitivity Method for Identification of IDH1 R132x Mutations in Tumors and Plasma of Intrahepatic Cholangiocarcinoma Patients

Hotspot codon 132 mutations (R132xIDH1m) are frequent in intrahepatic cholangiocarcinoma (ICC), are druggable by anti-IDH1m agents, and could represent a marker of disease progression. Developing an assay to identify R132xIDH1m would provide a useful tool to select patients benefitting from targeted treatments. We tested a quantitative real-time allele-specific polymerase chain reaction (qPCR)-based method to detect the main R132xIDH1m in an Italian ICC series (n = 61) of formalin-fixed paraffin-embedded (FFPE) samples, and on circulating-free DNA samples. The outcomes were compared with nested PCR/Sanger sequencing. Reconstitution experiments of plasmids harboring the different R132xIDH1m mixed with wild-type (WT) DNA demonstrated that qPCR is able to detect at least 2% of all mutated allele. High efficiency was also observed on patient-derived mutated DNA mixed with WT DNA (up to 10% and 0.3 ng of mutated template); qPCR detected 16.4% of mutated samples (one R132G, three R132C and six R132L) while nested PCR/Sanger sequencing only 8.2% (four R132L and one R132G). In a single patient with an R132C-mutated tumor, qPCR was also performed on plasma samples collected at four time-points, observing an increase correlating with disease progression. In conclusion, we developed a qPCR assay which could represent a fast, inexpensive and sensitive tool both for detection of R132xIDH1m in ICC samples and monitoring disease progression from liquid biopsy.

Biliary tract cancers: current knowledge, clinical candidates and future challenges

Biliary tract cancers (BTCs) are rare with poor prognosis. Due to the advent of genomic sequencing, new data have emerged regarding the molecular makeup of this disease. To add to the complexity, various subtypes also harbor a varied genetic composition. The commonly mutated genes associated with this cancer are KRAS, EGFR, IDH, FGFR and BAP1. Various clinical studies are looking at targeting these genetic mutations. Another therapeutic area of note is the potential for the use of immunotherapy in patients with BTC. Although BTC may be a result of chronic inflammation, this does not necessarily translate into increased immunogenicity. This literature review discusses the diverse molecular and immune-related pathways in patients with BTC and their potential therapeutic implications.

Gallbladder Cancer: Diagnosis, Surgical Management, and Adjuvant Therapies

Gallbladder cancer (GBC) is an often lethal disease, but surgical resection is potentially curative. Symptoms may be misdiagnosed as biliary colic; over half of new diagnoses are made after laparoscopic cholecystectomy for presumed benign disease. Gallbladder polyps >1 cm should prompt additional imaging and cholecystectomy. For GBC diagnosed after cholecystectomy, tumors T1b and greater necessitate radical cholecystectomy. Radical cholecystectomy includes staging laparoscopy, hepatic resection, and locoregional lymph node clearance to achieve R0 resection. Patients with locally advanced disease (T3 or T4), hepatic-sided T2 tumors, node positivity, or R1 resection may benefit from adjuvant chemotherapy. Chemotherapy increases survival in unresectable disease.

Somatic mutation profiling of liver and biliary cancer by targeted next generation sequencing

Liver and biliary cancers are highly lethal cancer types lacking effective treatments. The somatic mutations, particularly those with low mutant allele frequencies, in Chinese patients with liver and biliary cancer have not been profiled, and the frequency of patients benefiting from targeted therapy has not been studied. The present study evaluated the tumor tissues of 45 Chinese patients with hepatocellular carcinoma (HCC) and 12 Chinese patients with biliary tract cancer (BTC) by targeted next generation sequencing, with an average coverage of 639×, to identify alterations in 372 cancer-related genes. A total of 263 variants were identified in 139 genes, with 85.6% of these variants not previously reported in the Catalogue Of Somatic Mutations In Cancer database, and the mutation profile was different from the current datasets, including The Cancer Genome Atlas dataset and the National Cancer Center Japan (NCC_JP) dataset. Patients with hepatitis B virus (HBV) infection harbored more mutations than those without HBV infection, and the mutations in HBV carriers occurred preferentially in genes involved in vascular endothelial growth factor signaling pathways. Mutations in fibroblast growth factor and RAS signaling pathways were enriched in patients with cirrhosis, and alterations in interleukin and transforming growth factor signaling pathways were more frequently identified in individuals with abnormal bilirubin expression. Of all the patients, 7% exhibited variants in the target of sorafenib, and 42% harbored variants in the targets of drugs that have been approved to treat other types of cancer. These findings indicate diverse HCC/BTC variants patterns in different populations, and that the mutation load and patterns are correlated with clinical features. Further clinical studies are now warranted to evaluate the efficacies of other targeted drugs besides sorafenib in the treatment of patients with liver and biliary cancer.

Systemic and Adjuvant Therapies for Intrahepatic Cholangiocarcinoma

Intrahepatic cholangiocarcinoma represents the second most common primary liver cancer and is increasing in incidence. Most patients are diagnosed at an advanced, nonsurgical stage and only about 1 in 5 cases are surgically resectable. Despite surgery, the 5-year survival is low at only 30%. Multifocal, node- or margin-positive disease is at a higher risk of recurrence after resection. There is no level 1 evidence in support of postoperative adjuvant therapy. A recent adjuvant therapy phase III trial from the Partenariat de Recherche en Oncologie Digestive-Actions Concertées dans les Cancers Colo-Rectaux et Digestifs (PRODIGE) group reported no survival advantage with adjuvant gemcitabine and oxaliplatin therapy. Locally advanced or metastatic cholangiocarcinoma is treated with gemcitabine-based systemic chemotherapy with suboptimal response and survival. Integration of local therapy such as focal radiation along with induction chemotherapy is now being investigated in multicenter clinical trials. Recent molecular profiling studies have indicated that about 30% to 40% of intrahepatic cholangiocarcinoma cases have actionable mutations. These include fibroblast growth factor receptor (FGFR), isocitrate dehyrogenase 1 (IDH1), epidermal growth factor receptor (EGFR), and BRAF genetic aberrations. Clinical trials targeting these mutations as well as immune therapy using programmed cell death 1 (PD1) inhibitors indicated a promising early signal showing clinical efficacy.

Biomarker-Driven and Molecular Targeted Therapies for Hepatobiliary Cancers

The recent accumulation of molecular profiling data for primary hepatobiliary malignancies, including hepatocellular carcinoma and biliary tract cancers, has led to a proliferation of promising therapeutic investigations in recent years. Treatment with pathway-specific targeted inhibitors and immunotherapeutic agents have demonstrated promising early clinical results. Key molecular alterations in common hepatobiliary cancers and ongoing interventional clinical trials of molecularly targeted systemic agents focusing on hepatocellular carcinoma and biliary tract cancer are reviewed.

Emerging molecular target antagonists for the treatment of biliary tract cancer

INTRODUCTION

Biliary tract cancers (BTCs) are a heterogeneous group of cancers, characterized by low incidence but poor prognosis. Even after complete surgical resection for early stage, relapse is frequent and the lack of effective treatments contributes to the dismal prognosis. To date, the only standard treatment in first-line is cisplatin/gemcitabine combination, whereas no standard in 2nd-line has been defined. Hence, the current goal is to better understand the biology of BTCs, discovering new treatment methods and improving clinical outcomes. Areas covered: The development of next-generation-sequencing has unveiled the picture of the molecular signatures characterizing BTCs, leading to the identification of actionable mutations in biomarker-driven clinical trials. In this review we will cover the genetic landscape of BTC, focusing on the efficacy of existing treatments. Furthermore, we will discuss emerging molecular targets and evaluate the findings of pre-clinical studies. Finally, the encouraging results of clinical trials involving targeted therapies or immunotherapy will be reviewed. Expert opinion: FGFR fusion rearrangements and IDH1 or IDH2 mutations are the most promising targeted treatments under evaluation. In addition, innovative trial design will allow to offer a chance for tailored medicine to infrequent subgroups of BTCs patients based on their molecular features rather than their histology.

Investigation of targetable predictive and prognostic markers in gallbladder carcinoma

Background

Gallbladder carcinoma, uncommon in most of the world, is frequent in South East Asia. It presents in advanced stages with limited therapeutic options. We investigated targetable predictive and prognostic Markers in 268 cases including 233 primary site lesions and 35 metastatic gallbladder carcinoma.

Methods

EGFR, VEGF, HER2/Neu and p53 were assessed using immunohistochemistry. HER2/Neu was validated in a subset by fluorescent in situ hybridization (FISH) using tissue microarray (TMA). Broader spectrum of gene variation was screened in NGS in representative FFPE tissue using the Ion AmpliSeq cancer hotspot panel V2.

Results

Mean age was 49.5 years with female predominance (77.6%). Histological types included 221 cases of adenocarcinoma not otherwise specified (NOS), 23 invasive papillary carcinoma, 11 mucinous adenocarcinoma, 8 adenosquamous, 1 signet ring, 3 neuroendocrine and 1 undifferentiated carcinoma. Majority (76.1%) presented with stage 3/4 disease. Overall positive expression of p53 was 44.8%, VEGF 79.4%, HER2/Neu 27.3% and EGFR 34.6%. Intratumoral heterogeneity was evident in HER2/Neu. Marker expression was not significantly associated with stage, grade, type and metastasis except VEGF which correlated with histological type (P=0.018) and tumor grade (P=0.027). NGS using Ion AmpliSeq cancer hotspot panel V2 revealed multiple non synonymous mutations, most frequent being TP53 and CDKN2A mutations and mutations in MET, KDR, PIK3CA, VHL, MPL, HER2 and SMARCB1 genes.

Conclusions

Predictive targetable markers like HER2/Neu, VEGF and EGFR are expressed in high proportion of gallbladder carcinoma. Significant expression of RAS pathway molecules suggests that interactions take place among the different members of the ErbB family during tumor development.

Prognostic and predictive role of EGFR pathway alterations in biliary cancer patients treated with chemotherapy and anti-EGFR

The association of anti-EGFR to gemcitabine and oxaliplatin (GEMOX) chemotherapy did not improve survival in biliary tract carcinoma (BTC) patients. Multiple mechanisms might be involved in the resistance to anti-EGFR. Here, we explored the mutation profile of EGFR extracellular domain (ECD), of tyrosine kinase domain (TKD), and its amplification status. EGFR mutational status of exons 12, 18–21 was analyzed in 57 tumors by Sanger sequencing. EGFR amplification was evaluated in 37 tumors by Fluorescent In Situ Hybridization (FISH). Kaplan-Meier curves were calculated using the log-rank test. Six patients had mutations in exon 12 of EGFR ECD and 7 in EGFR TKD. Neither EGFR ECD nor TKD mutations affected progression free survival (PFS) or overall survival (OS) in the entire population. In the panitumumab plus GEMOX (P-GEMOX) arm, ECD mutated patients had a worse OS, while EGFR TKD mutated patients had a trend towards shorter PFS and OS. Overall, the presence of mutations in EGFR or in its transducers did not affect PFS or OS, while the extrahepatic cholangiocarcinoma (ECC) mutated patients had a worse prognosis compared to WT. Nineteen out of 37 tumors were EGFR amplified, but the amplification did not correlate with survival. ECC EGFR amplified patients had improved OS, whereas the amplification significantly correlated with poor PFS (p = 0.03) in gallbladder carcinoma patients. The high molecular heterogeneity is a predominant feature of BTC: the alterations found in this work seem to have a prognostic impact rather than a predictive role towards anti-EGFR therapy.

Phase I dose-escalation study of copanlisib in combination with gemcitabine or cisplatin plus gemcitabine in patients with advanced cancer

Background:

Copanlisib is a pan-class I phosphatidylinositol 3-kinase (PI3K) inhibitor with predominant PI3K-α/δ activity that has demonstrated clinical activity and manageable safety when administered as monotherapy in a phase II study. Combination therapy may overcome compensatory signalling that could occur with PI3K pathway inhibition, resulting in enhanced inhibitory activity, and preclinical studies of copanlisib with gemcitabine have demonstrated potent anti-tumour activity in vivo.

Methods:

A phase I, open-label, dose-escalation study to evaluate the safety, tolerability and recommended phase II dose (RP2D) of copanlisib with gemcitabine or with cisplatin plus gemcitabine (CisGem) in patients with advanced malignancies, including an expansion cohort in patients with biliary tract cancer (BTC) at the RP2D of copanlisib plus CisGem. Copanlisib and gemcitabine were administered on days 1, 8 and 15 of a 28-day cycle; maximum tolerated dose (MTD) and RP2D of copanlisib were determined. Copanlisib plus CisGem was administered on days 1 and 8 of a 21-day cycle; pharmacokinetics and biomarkers were assessed.

Results:

Fifty patients received treatment as follows: dose-escalation cohorts, n=16; copanlisib plus CisGem cohort, n=14; and BTC expansion cohort, n=20. Copanlisib 0.8 mg kg⁻¹ plus gemcitabine was the MTD and RP2D for both combinations. Common treatment-emergent adverse events included nausea (86%), hyperglycaemia (80%) and decreased platelet count (80%). Copanlisib exposure displayed a dose-proportional increase. No differences were observed upon co-administration of CisGem. Response rates were as follows: copanlisib plus gemcitabine, 6.3% (one partial response in a patient with peritoneal carcinoma); copanlisib plus CisGem, 12% (one complete response and three partial responses all in patients with BTC (response rate 17.4% in patients with BTC)). Mutations were detected in PIK3CA (1 out of 43), KRAS (10 out of 43) and BRAF (2 out of 22), with phosphate and tensin homologue protein loss in 41% (12 out of 29).

Conclusions:

Copanlisib plus CisGem demonstrated a manageable safety profile, favourable pharmacokinetics, and potentially promising clinical response.

Drug development and clinical trial design in pancreatico-biliary malignancies

Pancreatico-biliary (P-B) tumors arise from the pancreas, bile duct, and ampulla of Vater. Despite their close anatomical location, they have different etiology and biology. However, they uniformly share a poor prognosis, with no major improvements observed in overall survival over decades, even in the face of progress in diagnostic imaging and surgical techniques, and advances in systemic and loco-regional radiation therapies. To date, cytotoxic treatment has been associated with modest benefits in the advanced disease setting, and survival for patients with stage IV disease has not exceeded a year. Therefore, there is a pressing need to identify better treatments which may impact more significantly. Frequently, encouraging signals of potential efficacy for novel agents in early phase clinical trials have been followed by disappointing failures in larger phase III trials, raising the valid question of how drug development can be optimized for patients with pancreatic adenocarcinoma and biliary tract malignancies. In this article we summarize the current therapeutic options for these patients and their limitations. The biological context of these cancers is reviewed, highlighting features that may make them resistant to standard chemotherapeutics and could be potential therapeutic targets. We discuss the role of early phase clinical trials, defined as phase I and non-randomised phase II trials, within the clinical context and current therapeutic landscape of P-B tumors and postulate how translational studies and trial design may enable better realization of emerging targets together with a proposed model for future patient management. A detailed summary of current phase I clinical trials in P-B tumors is provided.

Genotyping and mRNA profiling reveal actionable molecular targets in biliary tract cancers

Biliary tract cancer (BTC) represents a heterogeneous disease with dismal outcome. Herein, we examined genotype and angiogenesis features in BTC. We applied genotyping (Sanger, qPCR, 101-gene panel NGS), mRNA relative quantification methods, and β-catenin immunohistochemistry in 84 FFPE BTC (55 gallbladder [GBC], 14 intrahepatic [ICC], 15 extrahepatic [ECC] carcinomas). We identified 541 mutations in 68 (81%) tumors. Top mutated genes were CTNNB1 (36%); PTEN (33%); TP53 (31%); PIK3R1 (29%); PIK3CA (13%); BRCA2 and KRAS (12%); BRCA1 (11%). Six GBCs were hypermutated [hm] displaying a distinct mutational pattern. Mutations in TP53 and PI3K, Wnt and RAS components were prevalent among non-hypermutated tumors. All hmGBCs carried mutations in BRCA2 and other homologous recombination repair (HRR) genes, in PD1, but not in CTNNB1 and KRAS. None of the pathogenic BRCA2 p.D2723G and BRCA1 p.Q563* and c.5266dupC was present at frequencies expected for germline mutations. We observed copy gains (>6 copies) in EGFR (9% of informative tumors), PRKAR1A (7%), PIK3CA (6%), ERBB2 (5%) and MET (4%). TP53 mutations were prevalent in GBC (P<0.001) and PRKAR1A copy gains in ICC (P=0.007). PTEN was frequently co-mutated with CTNNB1 (P<0.001). Unrelated to CTNNB1 mutations, nuclear β-catenin was detected in 45% of tumors, among them in 5/6 hmGBC. We observed strong mRNA expression correlation of the two neuropilins (NRP1 and NRP2) with each other (Spearman's rho 0.59) and with the endothelin receptor (NRP2 rho 0.66; NRP2 rho 0.51), and between VEGFA and its receptors (FLT1 rho 0.49; KDR rho 0.45). All PIK3CA mutated tumors expressed endothelin 1 mRNA (P=0.010). Most tumors expressing nuclear β-catenin were negative for VEGFC (P=0.009) and FLT4 (P=0.002) mRNA expression. In conclusion, we confirmed the presence of known genomic aberrations in BTC and different genotypes between BTC subsets. Novel findings are the coexistence of PI3K and WNT pathway gene alterations in BTC, their association with angiogenesis, and the hypermutated GBCs with HRR gene mutations, all of which may be considered for new treatment options in this difficult to treat disease.

Hypermutation and microsatellite instability in gastrointestinal cancers

Recent progress in cancer genome analysis using next-generation sequencing has revealed a high mutation burden in some tumors. The particularly high rate of somatic mutation in these tumors correlates with the generation of neo-antigens capable of eliciting an immune response. Identification of hypermutated tumors is therefore clinically valuable for selecting patients suitable for immunotherapy treatment. There are several known causes of hypermutation in tumors, such as ultraviolet light in melanoma, tobacco smoke in lung cancer, and excessive APOBEC (apolipoprotein B mRNA editing enzyme, catalytic polypeptide-like) activity in breast and gastric cancer. In gastrointestinal cancers, one of the leading causes of hypermutation is a defect in DNA mismatch repair, which results in microsatellite instability (MSI). This review will focus on the frequency, characteristics and genomic signature of hypermutated gastrointestinal cancers with MSI. Detection of tumor hypermutation in cancer is expected to not only predict the clinical benefit of immune checkpoint inhibitor treatment, but also to provide better surgical strategies for the patients with hypermutated tumors. Thus, in an era of precision medicine, identification of hypermutation and MSI will play an important role directing surgical and chemotherapeutic treatment.

Current biologics for treatment of biliary tract cancers

Biliary tract cancers (BTC) is a group of malignancies that arise from the epithelial cells of the biliary tree. These cancers are typically classified by anatomic site of origin: intrahepatic cholangiocarcinoma (IHCC) and extrahepatic cholangiocarcinoma (EHCC), and gallbladder cancer (GBC). To date, complete surgical resection remains the mainstay of treatment especially for earlier stage disease. Unfortunately, most patients present with advanced or metastatic disease, when systemic chemotherapy is the only treatment option. Due to the paucity of effective treatments, BTCs have a dismal prognosis. There is a tremendous need to better understand the disease biology, discover new therapies, and improve clinical outcomes for this challenging disease. Next-generation sequencing has produced a more accurate and detailed picture of the molecular signatures in BTCs. The three BTC histologic subtypes are, in fact, quite molecularly distinct. IHCC commonly contain FGFR2 fusions and IDH 1 and 2 mutations, whereas EHCC and GBC tend to carry mutations in EGFR, HER2, and MAPK pathway. In light of this emerging knowledge, clinical trials have become more biomarker-driven, which allows capturing of subsets of patients that are most likely to respond to certain therapies. Many new and promising targeted therapeutics are currently in the pipeline. Here we review the genetic landscape of BTCs while focusing on new molecular targets and targeted therapeutics currently being investigated in biomarker-driven clinical trials.

The potential role of comprehensive genomic profiling to guide targeted therapy for patients with biliary cancer

Remarkable advancements in techniques of genomic profiling and bioinformatics have led to the accumulation of vast amounts of knowledge on the genomic profiles of biliary tract cancer (BTC). Recent largescale molecular profiling studies have not only highlighted genomic differences characterizing tumors of the intrahepatic and extrahepatic bile ducts and gallbladder, but have also revealed differences in genomic profiles pertaining to associated risk factors. Novel genomic alterations such as FGFR2 fusions and IDH1/2 mutations in intrahepatic cholangiocarcinoma (ICC) and ERBB2 alterations in gallbladder cancer (GBCA) are emerging as targeted therapy options capable of advancing precision medicine for the care of these patients. Moreover, variable genomic alterations also appear to impact prognosis and overall disease outcome independent from their therapy selection value. High mutational burden and increased expression of immune checkpoint-related proteins observed in a subset of BTC also show a potential for guidance of immunotherapy. Thus, comprehensive genomic profiling (CGP) is rapidly achieving status as an integral component of precision medicine and is starting to become invaluable in guiding the management of patients with BTC, a rare disease with dismal outcome.

Combined dabrafenib and trametinib treatment in a case of chemotherapy-refractory extrahepatic BRAF V600E mutant cholangiocarcinoma: dramatic clinical and radiological response with a confusing synchronic new liver lesion

Since the prognosis of advanced cholangiocarcinoma (CCA) remains poor with traditional chemotherapy, attention has shifted to molecularly targeted agents. Results of available clinical studies reveal little or no benefit of using targeted agents in advanced CCA. Limitations of these trials could be the lack of comprehensive molecular and genetic characterization of CCA samples in order to identify potential drug targets. Here we report a case of a 59-year-old female with chemotherapy-refractor, metastatic extrahepatic cholangiocarcinoma (EHCCA). After failure of first-line chemotherapy with cisplatin plus gemcitabine, next generation sequencing (NGS) based tumor molecular profiling was performed on aspiration cytological sample, that revealed BRAF V600E mutation. Multidisciplinary team decided on the initiation of combined treatment with BRAF and MEK inhibitors. Dabrafenib was started orally 150 mg twice a day, adding trametinib 2 mg once a day. Right from the initiation of targeted therapy, significant clinical improvement had been observed. Even though the first restaging computed tomography (CT) scan at 8 weeks revealed spectacular decrease in all metastatic sites, a new hepatic mass of 67 mm × 40 mm was identified and interpreted as new metastatic lesion. As the clinical and radiological response was contradictory, CT-guided biopsy was taken from the hepatic lesion while the therapy was continued on. Histopathologic evaluation excluded the hepatic lesion from being a metastasis, instead described it as a fibrotic, inflammatory lesion. At 12 week, PET CT confirmed further tumor regression with complete regression of the multiple cerebral metastases. The therapy has been extremely well tolerated by the patient. According to our knowledge, this is the first reported case on a successful treatment of EHCCA with the combination of dabrafenib and trametinib. Our case highlights the importance of molecular profiling in CCA, in order to find potential actionable driver mutations for personalised treatment.

Management of unresectable intrahepatic cholangiocarcinoma: how do we decide among the various liver-directed treatments?

Intrahepatic cholangiocarcinoma often causes death due to obstruction of the biliary system or interruption of the vascular supply of the liver. This fact emphasizes the critical need for local tumor control in this disease. Successful local tumor control has traditionally been achievable through surgical resection for the small proportion of patients with operable tumors. Technological advances in radiation oncology and in interventional radiology have enabled the delivery of ablative radiation doses or other cytotoxic therapies for tumors in the liver. In some cases, this has translated into substantial prolongation of life for patients with this disease, but the indications for these different treatment options are still the subject of ongoing debate. Here, we review the technological advances and clinical studies that are changing the way intrahepatic cholangiocarcinoma is managed, and discuss ways to achieve individualized treatment of patients.

New molecular and immunotherapeutic approaches in biliary cancer

Biliary tract carcinoma is a collective term for a group of rare gastrointestinal cancers. This overview outlines the key pathways and specialised therapeutics in biliary cancer and the emerging role of immunotherapy by highlighting the rationale and selected examples of studies in each area.