New and emerging treatment options for biliary tract cancer

Circulating Cell-Free DNA-Based Comprehensive Molecular Analysis of Biliary Tract Cancers Using Next-Generation Sequencing

Biliary tract cancer (BTC) is a rare malignancy with a long disease course and an overall poor prognosis. Despite multiple chemotherapy agents, there is no defined second-line treatment opportunity for advanced BTCs. In the era of precision oncology, NGS plays an important role in identifying mutations that may predict the molecular pathomechanism and manage the BTC therapy. The peripheral blood liquid biopsy (LB) of cancer patients represents variable amounts of cell-free DNA (cfDNA) released from tumor foci of any anatomical location. Our study aimed to identify somatic mutations and tumor variant burden (TVB) in cell-free and matched tumor DNA. We found a positive correlation between the estimated tumor volume and cfDNA yield (r = 0.9326, p < 0.0001). Comparing tissue and LB results, similar TVB was observed. SNVs were proven in 84% of the cases, while in two cases, only the LB sample was informative for molecular analysis. The most important aberrations in BTCs, such as FGFR2, IDH1, IDH2, KRAS, and TP53, could be detected in matched LB samples. Our prospective study demonstrates a minimally invasive testing approach to identify molecular genetic alterations in cholangiocarcinoma and gallbladder cancers. Clinical applications of cfDNA reflect by capturing the outstanding spatial tumor heterogeneity and guarantee novel aspects for the precision oncology treatment.

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.

Pancreatic intraductal tubulopapillary neoplasm is genetically distinct from intraductal papillary mucinous neoplasm and ductal adenocarcinoma

Intraductal tubulopapillary neoplasm is a relatively recently described member of the pancreatic intraductal neoplasm family. The more common member of this family, intraductal papillary mucinous neoplasm, often carries genetic alterations typical of pancreatic infiltrating ductal adenocarcinoma (KRAS, TP53, and CDKN2A) but additionally has mutations in GNAS and RNF43 genes. However, the genetic characteristics of intraductal tubulopapillary neoplasm have not been well characterized. Twenty-two intraductal tubulopapillary neoplasms were analyzed by either targeted next-generation sequencing, which enabled the identification of sequence mutations, copy number alterations, and selected structural rearrangements involving all targeted (≥300) genes, or whole-exome sequencing. Three of these intraductal tubulopapillary neoplasms were also subjected to whole-genome sequencing. All intraductal tubulopapillary neoplasms revealed the characteristic histologic (cellular intraductal nodules of back-to-back tubular glands lined by predominantly cuboidal cells with atypical nuclei and no obvious intracellular mucin) and immunohistochemical (immunolabeled with MUC1 and MUC6 but were negative for MUC2 and MUC5AC) features. By genomic analyses, there was loss of CDKN2A in 5/20 (25%) of these cases. However, the majority of the previously reported intraductal papillary mucinous neoplasm-related alterations were absent. Moreover, in contrast to most ductal neoplasms of the pancreas, MAP-kinase pathway was not involved. In fact, 2/22 (9%) of intraductal tubulopapillary neoplasms did not reveal any mutations in the tested genes. However, certain chromatin remodeling genes (MLL1, MLL2, MLL3, BAP1, PBRM1, EED, and ATRX) were found to be mutated in 7/22 (32%) of intraductal tubulopapillary neoplasms and 27% harbored phosphatidylinositol 3-kinase (PI3K) pathway (PIK3CA, PIK3CB, INPP4A, and PTEN) mutations. In addition, 4/18 (18%) of intraductal tubulopapillary neoplasms had FGFR2 fusions (FGFR2-CEP55, FGFR2-SASS6, DISP1-FGFR2, FGFR2-TXLNA, and FGFR2-VCL) and 1/18 (5.5%) had STRN-ALK fusion. Intraductal tubulopapillary neoplasm is a distinct clinicopathologic entity in the pancreas. Although its intraductal nature and some clinicopathologic features resemble those of intraductal papillary mucinous neoplasm, our results suggest that intraductal tubulopapillary neoplasm has distinguishing genetic characteristics. Some of these mutated genes are potentially targetable. Future functional studies will be needed to determine the consequences of these gene alterations.

Activation or suppression of the immune response mediators in biliary tract cancer (BTC) patients: a systematic review and meta-analysis

Background: Infiltration of immune cells and immune microenvironment determine the proliferative activity of the tumor and metastasis. The aim of this study was to analyze the influence of activation or suppression of the immune response mediators on the prognosis of biliary tract cancer (BTC). Methods: We searched Pubmed, Web of Science, Embase and The Cochrane Library for relevant literatures until June 2016. The quality of studies was assessed by QUADAS-2 and NOS tools. Forest and funnel plots and all statistical analyses were generated by using Review Manager 5.3. The bias of included studies was estimated by Egger's test using Meta R package. Results: A total of 2339 patients from 12 studies were finally enrolled in this meta-analysis. Patients with high expression of immune active factors, intraepithelial tumor-infiltrating CD4+ , CD8+, and Foxp3+ T lymphocytes, MHC I, NKG2D, showed a better overall survival (OS) than those with low expression (HR=0.52, 95% CI=0.41-0.67, P<0.00001). On the contrary, the high expression of immune suppressive factors (CD66b+ neutrophils, Neutrophil-lymphocyte ratio, Intratumoral IL-17+ cells and PD-1+/CD8+ TILs) was significantly associated with poor OS (HR=1.79, 95% CI=1.44-2.22, P<0.00001). A further analysis of therapies targeting tumor microenvironment modulation showed that the median progression free survival (PFS) for BTC patients who received adjuvant immunotherapy was longer than those who received surgery or chemotherapy alone, and the estimated pooled mean difference demonstrated a highly significant improvement (MD =2.33; 95% CI: 0.63-4.02, P=0.007). The total effect of PFS and OS was statistically longer in experimental group, compared to patients in control groups, respectively (PFS: RR=1.25; 95% CI: 1.08-1.46, P=0.004; OS: RR=1.16; 95% CI: 1.07-1.27, P=0.0006). In subgroup meta-analysis of studies on 6-, 12- and 18-month PFS and OS, it showed that adjuvant immunotherapy could improve the 6-month PFS (RR=1.23; 95% CI: 1.05-1.44, P=0.009), and 6-month OS (RR=1.17; 95% CI: 1.06-1.30, P=0.002). Conclusions: So given the above issue, our meta-analysis confirmed that the level of immune mediators could be a predicative factor for prognosis of BTC patients, and immunotherapy regimens by modulating the tumor microenvironment was superior for enhancing median PFS, 6-month PFS and OS.

Efficacy and toxicities of adding molecular targeted agents to first-line chemotherapy in the treatment of advanced biliary tract cancer: a systematic review and meta-analysis

Purpose

The purpose of this study was to assess the efficacy and toxicities of adding molecular targeted agents (MTAs) to first-line chemotherapy in the treatment of advanced biliary tract cancer (BTC).

Methods

An extensive search for relevant clinical trials was conducted in electronic databases (PubMed, Web of Science, and Cochrane) and abstracts presented at meetings. Prospective randomized controlled trials (RCTs) reporting the efficacy and toxicity of chemotherapies with or without MTAs in advanced BTC were selected. The endpoints were overall survival (OS), progression-free survival (PFS), and grade 3 or 4 toxicities. The results were expressed as hazard ratio or relative risk (RR), with their corresponding 95% confidence intervals.

Results

The final analysis included a total of 855 advanced BTC patients from six RCTs. Compared with chemotherapy alone, the combination of MTAs with chemotherapy significantly improved overall response rate (ORR) (RR 1.68, 95% confidence interval: 1.28–2.19, P<0.001). And there was also a tendency to improve PFS in the combination regimens (hazard ratio 0.89, 95% confidence interval: 0.78–1.02, P=0.097) but not for OS (hazard ratio 1.01, 95% confidence interval: 0.90–1.13, P=0.93). Subgroup analysis according to targeted agents indicated that the addition of anti-epidermal growth factor receptor agents to chemotherapy significantly improved ORR and PFS, but it did not translate into OS benefits. Additionally, equivalent frequencies of grade 3 or 4 neutropenia, anemia, thrombocytopenia, nausea, and vomiting were found between the two groups excepting for diarrhea.

Conclusion

The present study indicates that the addition of anti-epidermal growth factor receptor agents to first-line chemotherapy in advanced BTC offers an improved ORR and PFS, but not for OS. Further RCTs with larger samples are warranted to confirm our findings.

Cholangiocarcinoma: from molecular biology to treatment

Cholangiocarcinoma is a rare tumor originating in the bile ducts, which, according to their anatomical location, is classified as intrahepatic, extrahepatic and hilar. Nevertheless, incidence rates have increased markedly in recent decades. With respect to tumor biology, several genetic alterations correlated with resistance to chemotherapy and radiotherapy have been identified. Here, we highlight changes in KRAS and TP53 genes that are normally associated with a more aggressive phenotype. Also IL-6 and some proteins of the BCL-2 family appear to be involved in the resistance that the cholangiocarcinoma presents toward conventional therapies. With regard to diagnosis, tumor markers most commonly used are CEA and CA 19-9, and although its use isolated appears controversial, their combined value has been increasingly advocated. In imaging terms, various methods are needed, such as abdominal ultrasound, computed tomography and cholangiopancreatography. Regarding therapy, surgical modalities are the only ones that offer chance of cure; however, due to late diagnosis, most patients cannot take advantage of them. Thus, the majority of patients are directed to other therapeutic modalities like chemotherapy, which, in this context, assumes a purely palliative role. Thus, it becomes urgent to investigate new therapeutic options for this highly aggressive type of tumor.

Intraductal tubulopapillary neoplasms of the bile ducts: clinicopathologic, immunohistochemical, and molecular analysis of 20 cases

Intraductal tubulopapillary neoplasm is a well-established entity in the pancreas. A similar, if not identical, tumor occurs also in the biliary tract. We conducted a multicenter study of 20 such lesions, focusing on their clinicopathologic characteristics and molecular profile. Biliary intraductal tubulopapillary neoplasms were seen in patients in their 60s (mean 62 years). The tumors were intrahepatic 70%, extrahepatic 10%, and perihilar 20%; mean tumor size was 6.9 cm. Histologically, all intraductal tubulopapillary neoplasms showed, in addition to their typical tubular pattern, solid areas (70%) or abortive papillae (50%). Necrosis was common (85%), predominantly focal (40%), and with 'comedocarcinoma-like pattern' in 40%. Immunohistochemically, these neoplasms were characterized by the expression of MUC1 (80%) and MUC6 (30%) and by the absence of MUC2 and MUC5AC. Associated invasive carcinomas were present in 16 (80%), mainly conventional tubular adenocarcinoma (50%). The molecular alterations observed included CDKN2A/p16 (intraductal components 44%, invasive 33%) and TP53 (intraductal components 17%, invasive 9%). Mutations in KRAS (intraductal 6%, invasive 0%), PIK3CA (intraductal 6%, invasive 0%), and loss of SMAD4/DPC4 (intraductal 7%, invasive 0%) were rare. No alterations/mutations were identified in IDH1/2, BRAF, GNAS, EGFR, HER2, and β-catenin. Follow-up information was available for 17 patients (85%) with mean follow-up 44 months. Overall combined survival rates showed favorable prognosis: 1 year 100%, 3 years 90%, and 5 years 90%. In conclusion, despite the relatively high incidence of invasive carcinoma (80%), available follow-up suggests that biliary intraductal tubulopapillary neoplasms have an indolent behavior. Molecular analyses highlight the low prevalence of alterations of common oncogenic signaling pathways in intraductal tubulopapillary neoplasm. Further studies using whole-exome sequencing are required to discover yet unknown molecular changes and to understand the carcinogenesis of intraductal tubulopapillary neoplasms.

Gemcitabine Plus Cisplatin for Advanced Biliary Tract Cancer: A Systematic Review

Evidence suggests that combined gemcitabine-cisplatin chemotherapy extends survival in patients with advanced biliary tract cancer (BTC). We conducted a systematic review in order to collate this evidence and assess whether gemcitabine-cisplatin efficacy is influenced by primary tumor site, disease stage, or geographic region, and whether associated toxicities are related to regimen. MEDLINE (1946-search date), EMBASE (1966-search date), ClinicalTrials. gov (2008-search date), and abstracts from major oncology conferences (2009- search date) were searched (5 Dec 2013) using terms for BTC, gemcitabine, and cisplatin. All study types reporting efficacy (survival, response rates) or safety (toxicities) outcomes of gemcitabine-cisplatin in BTC were eligible for inclusion; efficacy data were extracted from prospective studies only. Evidence retrieved from one meta-analysis (abstract), four randomized controlled trials, 12 nonrandomized prospective studies, and three retrospective studies supported the efficacy and safety of gemcitabine-cisplatin for BTC. Median overall survival ranged from 4.6 to 11.7 months, and response rate ranged from 17.1% to 36.6%. Toxicities were generally acceptable and manageable. Heterogeneity in study designs and data collected prevented formal meta-analysis, however exploratory assessments suggested that efficacy did not vary with primary tumor site (gallbladder vs. others), disease stage (metastatic vs. locally advanced), or geographic origin (Asia vs. other). Incidence of grade 3/4 toxicities was not related to gemcitabine dose or cisplatin frequency. Despite individual variation in study designs, the evidence presented suggests that gemcitabine-cisplatin is effective in patients from a diverse range of countries and with heterogeneous disease characteristics. No substantial differences in toxicity were observed among the different dosing schedules of gemcitabine and cisplatin.

Anticancer activity of streptochlorin, a novel antineoplastic agent, in cholangiocarcinoma

BACKGROUND

The aim of this study is to investigate the anticancer activity of streptochlorin, a novel antineoplastic agent, in cholangiocarcinoma.

METHODS

The anticancer activity of streptochlorin was evaluated in vitro in various cholangiocarcinoma cell lines for apoptosis, proliferation, invasiveness, and expression of various protein levels. A liver metastasis model was prepared by splenic injection of HuCC-T1 cholangiocarcinoma cells using a BALB/c nude mouse model to study the systemic antimetastatic efficacy of streptochlorin 5 mg/kg at 8 weeks. The antitumor efficacy of subcutaneously injected streptochlorin was also assessed using a solid tumor xenograft model of SNU478 cells for 22 days in the BALB/c nude mouse.

RESULTS

Streptochlorin inhibited growth and secretion of vascular endothelial growth factor by cholangiocarcinoma cells in a dose-dependent manner and induced apoptosis in vitro. In addition, streptochlorin effectively inhibited invasion and migration of cholangiocarcinoma cells. Secretion of vascular endothelial growth factor and activity of matrix metalloproteinase-9 in cholangiocarcinoma cells were also suppressed by treatment with streptochlorin. Streptochlorin effectively regulated metastasis of HuCC-T1 cells in a mouse model of liver metastasis. In a tumor xenograft study using SNU478 cells, streptochlorin significantly inhibited tumor growth without changes in body weight when compared with the control.

CONCLUSION

These results reveal that streptochlorin is a promising chemotherapeutic agent to the treatment of cholangiocarcinoma.

Diabetes mellitus and the risk of cholangiocarcinoma: an updated meta-analysis

INTRODUCTION

A number of studies have shown that diabetes mellitus is implicated in susceptibility to several cancers. However, the relationship between diabetes and cholangiocarcinoma remain unclear.

AIM

To quantitatively assess the relationship between diabetes and incidence of cholangiocarcinoma in cohort and case-control studies.

MATERIAL AND METHODS

A literature search was performed for entries from 1996 to 2014 using the PubMed and EMBASE databases. Studies were included if they reported odds ratios (OR) and corresponding 95% CI of cholangiocarcinoma with respect to diabetes mellitus.

RESULTS

Twenty studies met the inclusion criteria, which included fifteen case-control studies and five cohort studies from Asia (n = 11), the United States (n = 5), and Europe (n = 4). Compared with individuals without diabetes, the pooled OR of cholangiocarcinoma was 1.74 (95% CI: 1.62-1.87, p = 0.568 for heterogeneity) for patients with diabetes, ICC (summary RR, 1.93; 95% CI: 1.65-2.25; p = 0.037 for heterogeneity), and ECC (summary RR, 1.66; 95% CI: 1.39-1.98; p = 0.001 for heterogeneity). The funnel plot revealed no evidence for publication bias concerning diabetes and the risk of CC (including ICC and ECC).

CONCLUSIONS

The findings from this meta-analysis suggest that diabetes may increase the risk of cholangiocarcinoma. This relationship needs to be confirmed by further follow-up studies.