Extrahepatic Cholangiocarcinoma Research Articles

KRAS Allelic Variants in Biliary Tract Cancers

Biliary tract cancers (BTCs) contain several actionable molecular alterations, including FGFR2, IDH1, ERBB2 (formerly HER2), and KRAS. KRAS allelic variants are found in 20% to 30% of BTCs, and multiple KRAS inhibitors are currently under clinical investigation. To describe the genomic landscape, co-sequence variations, immunophenotype, genomic ancestry, and survival outcomes of KRAS-mutated BTCs and to calculate the median overall survival (mOS) for the most common allelic variants. This retrospective, multicenter, pooled cohort study obtained clinical and next-generation sequencing data from multiple databases between January 1, 2017, and December 31, 2022. These databases included Princess Margaret Cancer Centre, MD Anderson Cancer Center, Foundation Medicine, American Association for Cancer Research Project GENIE, and cBioPortal for Cancer Genomics. The cohort comprised patients with BTCs who underwent genomic testing. The main outcome was mOS, defined as date of diagnosis to date of death, which was measured in months. A total of 7457 patients (n = 3773 males [50.6%]; mean [SD] age, 63 [5] years) with BTCs and genomic testing were included. Of these patients, 5813 had clinical outcome data available, in whom 1000 KRAS-mutated BTCs were identified. KRAS allelic variants were highly prevalent in perihilar cholangiocarcinoma (28.6%) and extrahepatic cholangiocarcinoma (36.1%). Thirty-six KRAS allelic variants were identified, and the prevalence rates in descending order were G12D (41%), G12V (23%), and Q61H (8%). The variant G12D had the highest mOS of 25.1 (95% CI, 22.0-33.0) months compared with 22.8 (95% CI, 19.6-31.4) months for Q61H and 17.8 (95% CI, 16.3-23.1) months for G12V variants. The majority of KRAS-mutated BTCs (98.9%) were not microsatellite instability-high and had low tumor mutational burden (ranging from a median [IQR] of 1.2 (1.2-2.5) to a mean [SD] of 3.3 [1.3]). Immune profiling through RNA sequencing of KRAS and NRAS-mutated samples showed a pattern toward a more immune-inflamed microenvironment with higher M1 macrophage activation (0.16 vs 0.12; P = .047) and interferon-γ expression compared with wild-type tumors. The G12D variant remained the most common KRAS allelic variant in all patient ancestries. Patients with admixed American ancestry had the highest proportion of G12D variant (45.0%). This cohort study found that KRAS allelic variants were relatively common and may be potentially actionable genomic alterations in patients with BTCs, especially perihilar cholangiocarcinoma and extrahepatic cholangiocarcinoma. The findings add to the growing data on genomic and immune landscapes of KRAS allelic variants in BTCs and are potentially of value to the planning of specific therapies for this heterogeneous patient group.

Durvalumab plus gemcitabine and cisplatin in advanced biliary tract cancer (TOPAZ-1): patient-reported outcomes from a randomised, double-blind, placebo-controlled, phase 3 trial

In the ongoing, randomised, double-blind phase 3 TOPAZ-1 study, durvalumab, a PD-L1 inhibitor, plus gemcitabine and cisplatin was associated with significant improvements in overall survival compared with placebo, gemcitabine, and cisplatin in people with advanced biliary tract cancer at the pre-planned intermin analysis. In this paper, we present patient-reported outcomes from TOPAZ-1. In TOPAZ-1 (NCT03875235), participants aged 18 years or older with previously untreated, unresectable, locally advanced, or metastatic biliary tract cancer with an Eastern Cooperative Oncology Group performance status of 0 or 1 and one or more measurable lesions per Response Evaluation Criteria in Solid Tumors (RECIST; version 1.1) were randomly assigned (1:1) to the durvalumab group or the placebo group using a computer-generated randomisation scheme. Participants received 1500 mg durvalumab or matched placebo intravenously every 3 weeks (on day 1 of the cycle) for up to eight cycles in combination with 1000 mg/m2 gemcitabine and 25 mg/m2 cisplatin intravenously on days 1 and 8 every 3 weeks for up to eight cycles. Thereafter, participants received either durvalumab (1500 mg) or placebo monotherapy intravenously every 4 weeks until disease progression or other discontinuation criteria were met. Randomisation was stratified by disease status (initially unresectable vs recurrent) and primary tumour location (intrahepatic cholangiocarcinoma vs extrahepatic cholangiocarcinoma vs gallbladder cancer). Patient-reported outcomes were assessed as a secondary outcome in all participants who completed the European Organisation for Research and Treatment of Cancer's 30-item Quality of Life of Cancer Patients questionnaire (QLQ-C30) and the 21-item Cholangiocarcinoma and Gallbladder Cancer Quality of Life Module (QLQ-BIL21). We calculated time to deterioration-ie, time from randomisation to an absolute decrease of at least 10 points in a patient-reported outcome that was confirmed at a subsequent visit or the date of death (by any cause) in the absence of deterioration-and adjusted mean change from baseline in patient-reported outcomes. Between April 16, 2019, and Dec 11, 2020, 685 participants were enrolled and randomly assigned, 341 to the durvalumab group and 344 to the placebo group. Overall, 345 (50%) of participants were male and 340 (50%) were female. Data for the QLQ-C30 were available for 318 participants in the durvalumab group and 328 in the placebo group (median follow-up 9·9 months [IQR 6·7 to 14·1]). Data for the QLQ-BIL21 were available for 305 participants in the durvalumab group and 322 in the placebo group (median follow-up 10·2 months [IQR 6·7 to 14·3]). The proportions of participants in both groups who completed questionnaires were high and baseline scores were mostly similar across treatment groups. For global health status or quality of life, functioning, and symptoms, we noted no difference in time to deterioration or adjusted mean changes from baseline were observed between groups. Median time to deterioration of global health status or quality of life was 7·4 months (95% CI 5·6 to 8·9) in the durvalumab group and 6·7 months (5·6 to 7·9) in the placebo group (hazard ratio 0·87 [95% CI 0·69 to 1·12]). The adjusted mean change from baseline was 1·23 (95% CI -0·71 to 3·16) in the durvalumab group and 0·35 (-1·63 to 2·32) in the placebo group. The addition of durvalumab to gemcitabine and cisplatin did not have a detrimental effect on patient-reported outcomes. These results suggest that durvalumab, gemcitabine, and cisplatin is a tolerable treatment regimen in patients with advanced biliary tract cancer. AstraZeneca.

Management of biliary tract cancers in early-onset patients: A nested multicenter retrospective study of the ACABI GERCOR PRONOBIL cohort.

Accumulating data has shown the rising incidence and poor prognosis of early-onset gastrointestinal cancers, but few data exist on biliary tract cancers (BTC). We aimed to analyse the clinico-pathological, molecular, therapeutic characteristics and prognosis of patients with early onset BTC (EOBTC, age ≤50 years at diagnosis), versus olders. We analysed patients diagnosed with intrahepatic cholangiocarcinoma, extrahepatic cholangiocarcinoma, and gallbladder adenocarcinoma between 1 January 2003 and 30 June 2021. Baseline characteristics and treatment were described in each group and compared. Progression-free survival, overall survival and disease-free survival were estimated in each group using the Kaplan-Meier method. Overall, 1256 patients were included, 188 (15%) with EOBTC. Patients with EOBTC demonstrated fewer comorbidities (63.5% vs. 84.5%, p < .0001), higher tumour stage (cT3-4: 50.0% vs. 32.3%, p = .0162), bilobar liver involvement (47.8% vs. 32.1%, p = .0002), and metastatic disease (67.6% vs. 57.5%, p = .0097) compared to older. Patients with EOBTC received second-line therapy more frequently (89.5% vs. 81.0% non-EOBTC, p = .0224). For unresectable patients with BTC, median overall survival was 17.0 vs. 16.2 months (p = .0876), and median progression-free survival was 5.8 vs. 6.0 months (p = .8293), in EOBTC vs. older. In advanced stages, fewer actionable alterations were found in EOBTC (e.g., IDH1 mutations [7.8% vs. 16.6%]; FGFR2-fusion [11.7% vs. 8.9%]; p = .029). Patients with EOBTC have a more advanced disease at diagnosis, are treated more heavily at an advanced stage but show similar survival. A distinctive molecular profile enriched for FGRF2 fusions was found.

The Impact of Radiofrequency Ablation on Survival Outcomes and Stent Patency in Patients with Unresectable Cholangiocarcinoma: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

Endoluminal biliary radiofrequency ablation (RFA) has been proposed as a palliative treatment for patients with malignant biliary obstruction (MBO) in order to improve stent patency and survival. However, the existing data on patients with inoperable extrahepatic cholangiocarcinoma (eCCA) are conflicting. We performed a meta-analysis of randomized trials comparing RFA plus stenting versus stenting alone in patients with inoperable eCCA. We searched for trials published in the PubMed/MEDLINE, Scopus, and Cochrane databases up to November 2023. Data extraction was conducted from published studies, and a quality assessment was carried out in accordance with the guidelines recommended by the Cochrane Collaboration. Hazard ratios (HRs) with 95% CI were estimated from the trials. The primary endpoints of interest were overall survival and stent patency. Out of 275 results, 5 randomized trials and 370 patients were included. While overall survival was not different between the groups (HR 0.62; 95% CI 0.36-1.07; p = 0.09; I2 = 80%;), the subgroup analysis of studies employing plastic stents showed a trend toward better survival in the RFA-treated group (HR 0.42; 95% CI 0.22-0.80; p = 0.009; I2 = 72%). Stent patency was improved in patients receiving RFA (HR 0.64; 95% CI 0.45-0.90; p = 0.01; I2 = 23%). Adverse events were not different between the groups (OR 1.21; 95% CI 0.69-2.12; p = 0.50; I2 = 0%). Despite the promising results, high heterogeneity and potential biases in the included studies suggest the need for further high-quality randomized trials to explore the potential cumulative effects of RFA on CCA treatment outcomes.

Abstract 5132: Multi-omics analysis uncovers predictive biomarkers for the efficacy and outcomes of immune checkpoint inhibitor in combination with chemotherapy in advanced unresectable biliary tract cancers

Abstract Background: Biliary tract cancer, typically diagnosed at advanced stages with a poor prognosis, has witnessed a glimmer of hope in the progress of immune checkpoint inhibitors (ICIs). Yet, their limited response rates necessitate the search for effective biomarkers to refine patient selection. Methods: A total of 125 patients with a confirmed histological diagnosis of unresectable advanced or metastatic biliary tract cancers (BTC) who received first-line ICIs in combination with chemotherapy (chemoimmunotherapy) were prospectively enrolled. All baseline samples from 125 patients underwent targeted DNA sequencing, with an additional 62 patients undergoing RNA sequencing, and 85 patients had accessible mIHC data. The associations between molecular characteristics and the response to chemoimmunotherapy, progression-free survival (PFS) and overall survival (OS) were evaluated. Results: The cohort had a median age of 63 years (range from 34 to 82) and 52.8% (66/125) were male, including 54 with gallbladder cancer, 57 with intrahepatic cholangiocarcinoma, and 14 with extrahepatic cholangiocarcinoma. The median duration of follow-up was 14.8 months for the entire cohort, with the median PFS and OS of 6.9 months (95%CI: 6.2-7.9) and 11.8 months (95%CI: 10.3-14.8), respectively. The most mutated genes were TP53 (64/125, 51.2%), KRAS (34/125, 27.2%), ERBB2 (18/125, 14.4%), and ARID1A (17/125, 13.6%). Mutations of TP53 (51.2%, p = 0.042), BRCA2 (4.8%, p = 0.002), cytokine genes (6.4%, p = 0.004), and high tumor mutation burden (p = 0.072) demonstrated significant correlation with chemoimmunotherapy response. KRAS G12D mutations (PFS: P &amp;lt; 0.001; OS: P = 0.034) and ARID1A loss-of-function mutations (PFS: P = 0.009; OS: P = 0.012) were adverse survival factors, while high CXCL9 or CTLA4 expression was associated with response (CXCL9, P = 0.014; CTLA4, P = 0.067), improved PFS (CXCL9, P = 0.018; CTLA4, P = 0.008), and longer OS (CXCL9, P = 0.010; CTLA4, P = 0.008) under chemoimmunotherapy. Patients were classified into three subtypes using the identified survival biomarkers. Among them, Type I patients, characterized by the absence of KRAS G12D or ARID1A mutations but expressing high levels of CTLA4 or CXCL9, demonstrated the best outcomes under chemoimmunotherapy. Interestingly, further RNA analysis suggested that elevated CXCL9 expression correlated with heightened immune checkpoint expressions, including CTLA4, PD-L1, and PD-1 (all P &amp;lt; 0.001), as well as increased tumor microenvironment immune activity, findings validated in two additional independent patient cohorts both internal and external. Conclusions: Our study revealed predictive biomarkers relevant to the response and efficacy of immune checkpoint inhibitors in combination with chemotherapy in advanced biliary tract cancer. Citation Format: Jieer Ying, Qi Xu, Jiaojiao Ni, Hanlin Chen, Chaoqun Li, Yanru Xie, Qinhong Zheng, Jianying Jin, Junrong Yan, Xiaoying Wu, Qiuxiang Ou, Li Yuan, Wei Zhuo, Haimeng Tang. Multi-omics analysis uncovers predictive biomarkers for the efficacy and outcomes of immune checkpoint inhibitor in combination with chemotherapy in advanced unresectable biliary tract cancers [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5132.

Abstract 6422: Comprehensive proteogenomic profiling and biomarker analyses in resected extrahepatic cholangiocarcinoma: A prespecified exploratory analysis of the phase 2 STAMP trial

Abstract Background: Biliary tract cancer constitutes a heterogeneous group of diseases with a limited understanding of its molecular characteristics and prognostic/predictive biomarkers. We performed prespecified exploratory analyses of the STAMP trial, a multicenter randomized phase 2 trial of adjuvant capecitabine (CAP) or gemcitabine plus cisplatin (GemCis) for patients with resected extrahepatic cholangiocarcinoma (EH-CCA) with regional lymph node metastasis. Methods: Among 101 patients included in the intention-to-treat population of the STAMP trial, a total of 89 patients (45 in the GemCis group and 44 in the CAP group) were included in the current biomarker analysis after excluding 12 patients without available tissue and blood samples. Whole exome sequencing and proteomics were performed using surgical specimens. Results: TP53 (63%), SMAD4 (20%), and KRAS (18%) mutations were the most frequent in the pooled population. Somatic mutations in homologous recombination deficient (HRD) genes were present in 20% of patients, while one patient (1%) had a germline ATM mutation. The prevalence of microsatellite instability was 1%. Somatic mutations in known targetable genes were observed in 54 patients (60.7%) and proteogenomic integrative analysis revealed significant HER2 pathway alteration with HER2 amplification in 4 patients (7%). The characteristics of prognostic biomarkers varied by the adjuvant regimen used. In the adjuvant GemCis group, somatic mutations were associated with poor disease-free survival (DFS) and overall survival (OS), including KRAS (log-rank p=0.004 for DFS and p=0.003 for OS), FBXW7 (p=0.021 for DFS and p=0.011 for OS), and PIK3CA (p&amp;lt;0.001 for DFS and p=0.042 for OS) mutations. In the adjuvant CAP group, copy number alterations (CNAs) such as 8q24.21 amplification (p=0.006 for DFS and p=0.707 for OS) and 3q26.1 amplification (p=0.020 for DFS and p=0.026 for OS) were associated with poor survival, while 11q13.3 amplification (p=0.017 for DFS and p=0.099 for OS) was associated with improved survival. Additionally, a higher HRD score showed a tendency toward better DFS and OS in the GemCis group, but not in the CAP group, although it did not reach statistical significance in both groups (p&amp;gt;0.05). Non-negative matrix clustering of proteomics data classified patients into 4 clusters. Among those, cluster 2, which showed alterations in the metabolism pathway, was associated with higher CNA level, higher tendency of HRD scores, and favorable survival with GemCis (p=0.039 for DFS and p=0.100 for OS) but not with CAP. Conclusions: Comprehensive proteogenomic analyses enable the identification of prognostic biomarkers and may guide the selection of adjuvant chemotherapy in resected EH-CCA. Citation Format: Hyehyun Jeong, Ji-Hye Oh, Hee-Sung Ahn, Baek-Yeol Ryoo, Kyu-pyo Kim, Jae Ho Jeong, Inkeun Park, Seung-Mo Hong, Jinho Shin, Chae Won Park, Yoo Sook Cho, Kyunggon Kim, Chang Ohk Sung, Changhoon Yoo. Comprehensive proteogenomic profiling and biomarker analyses in resected extrahepatic cholangiocarcinoma: A prespecified exploratory analysis of the phase 2 STAMP trial [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 6422.

Retracted: Overexpression of 14-3-3δ Predicts Poor Prognosis in Extrahepatic Cholangiocarcinoma Patients.

[This retracts the article DOI: 10.1155/2020/8435420.].

Prognostic value of microRNA-21 in intra- and extrahepatic cholangiocarcinoma after radical resection: cohort study.

Prognostic value of microRNA-21 in intra- and extrahepatic cholangiocarcinoma after radical resection: cohort study.

Characterizing the burden of biliary tract cancers across 28 hospitals in Ontario, Canada.

The incidence of biliary tract cancers (BTC) appears to be increasing worldwide. We analyzed the characteristics of BTC-related hospitalizations under medical services across 28 hospitals in Ontario, Canada. This study uses data collected by GEMINI, a hospital research data network. BTC-related hospitalizations from 2015 to 2021 under the Department of Medicine or intensive care unit were captured using the International Classification of Diseases, 10th revision, codes for intrahepatic cholangiocarcinoma (iCCA), extrahepatic cholangiocarcinoma, and gallbladder cancers. A total of 4596 BTC-related hospitalizations (2720 iCCA, 1269 extrahepatic cholangiocarcinoma, 607 gallbladder cancers) were analyzed. The number of unique patients with BTC-related hospitalizations increased over time. For iCCA-related hospitalizations, the total number of hospitalizations increased (from 385 in 2016 to 420 in 2021, p=.005), the hospital length of stay decreased over the study period (mean 10days [SD, 12] in 2016 to 9days [SD, 8] in 2021, p=.04), and the number of in-hospital deaths was stable (from 68 [18%] in 2016 to 55 [13%] in 2021, p=.62). Other outcomes such as 30-day readmissions, medical imaging tests, intensive care unit-specific hospitalizations, and length of stay were stable over time for all cohorts. The cost of hospitalization for the BTC cohort increased from median $8203 CAD (interquartile range, 5063-15,543) in 2017 to $8507 CAD (interquartile range, 5345-14,755) in 2021. This real-world data analysis showed a rising number of patients with BTC-related hospitalizations and rising number of iCCA-related hospitalizations across 28 hospitals in Ontario between 2015 and 2021.

Projected Incidence of Hepatobiliary Cancers and Trends Based on Age, Race, and Gender in the United States.

Identifying the projected incidence of hepatobiliary cancers and recognizing patient cohorts at increased risk can help develop targeted interventions and resource allocation. The expected incidence of subtypes of hepatobiliary cancers in different age groups, races, and genders remains unknown. Historical epidemiological data from the Surveillance, Epidemiology, and End Results (SEER) database was used to project future incidence of hepatobiliary malignancies in the United States and identify trends by age, race, and gender. Patients ≥18 years of age diagnosed with a hepatobiliary malignancy between 2001 and 2017 were included. US Census Bureau 2017 National Population projects provided the projected population from 2017 to 2029. Age-Period-Cohort forecasting model was used to estimate future births cohort-specific incidence. All analyses were completed using R Statistical Software. We included 110381 historical patients diagnosed with a hepatobiliary malignancy between 2001 and 2017 with the following subtypes: hepatocellular cancer (HCC) (68%), intrahepatic cholangiocarcinoma (iCCA) (11.5%), gallbladder cancer (GC) (8%), extrahepatic cholangiocarcinoma (eCCA) (7.6%), and ampullary cancer (AC) (4%). Our models predict the incidence of HCC to double (2001 to 2029) from 4.5 to 9.03 per 100,000, with the most significant increase anticipated in patients 70-79 years of age. In contrast, incidence is expected to continue to decline among the Asian population. Incidence of iCCA is projected to increase, especially in the white population, with rates in 2029 double those in 2001 (2.13 vs. 0.88 per 100,000, respectively; p < 0.001). The incidence of GC among the black population is expected to increase. The incidence of eCCA is expected to significantly increase, especially among the Hispanic population, while that of AC will remain stable. The overall incidence of hepatobiliary malignancies is expected to increase in the coming years, with certain groups at increased risk. These findings may help with resource allocation when considering screening, treatment, and research in the coming years.

Differences in receipt of guideline-compliant care and survival for early-onset versus average-onset biliary tract cancers

BackgroundWe examined differences in receipt of guideline-compliant care in patients with early-onset versus average-onset biliary tract cancers (BTC) in localized or metastatic settings. Additionally, we examined associations between guideline compliance and overall survival (OS), stratified by age of onset and clinical stage. MethodsPatients with BTC [intrahepatic cholangiocarcinoma, gallbladder adenocarcinoma, extrahepatic cholangiocarcinoma] were identified within the National Cancer Database (2010–2018). Early onset was defined as diagnosis at < 50 and average onset at ≥ 70 years. Guideline-compliant care was defined as surgical resection ± chemotherapy for localized disease and multi-agent chemotherapy for metastatic disease. ResultsA total of 32,247 patients were identified, of whom 2855 patients (8.9%) had early-onset disease. Early-onset patients were more likely to have metastatic disease at presentation. Early-onset patients were more likely to receive guideline-compliant care in both localized (OR=2.24, 95% CI: 1.93–2.60) and metastatic (OR=4.40, 95% CI: 3.72–5.21) settings. Among patients with localized BTC, guideline compliance was associated with improved OS in both early (median OS: 51.9 vs. 13.5 months; HR=0.31, 95% CI: 0.27–0.37) and average-onset (median OS: 25.9 vs. 6.1 months; HR=0.31, 95% CI: 0.30–0.32) disease. Among patients with metastatic BTC, guideline compliance was associated with improved OS in both early (median OS: 10.1 vs. 3.5 months; HR=0.52, 95% CI: 0.43–0.62) and average-onset (median OS: 8.6 vs. 2.2 months; HR=0.45, 95% CI: 0.43–0.48) disease. ConclusionsEarly-onset BTC is associated with more frequent guideline-compliant care regardless of clinical stage. Guideline compliance is associated with improved OS regardless of age of onset or clinical stage.

PTEN deficiency induces an extrahepatic cholangitis-cholangiocarcinoma continuum via aurora kinase A in mice

The PTEN-AKT pathway is frequently altered in extrahepatic cholangiocarcinoma (eCCA). We aim to evaluate the role of PTEN in the pathogenesis of eCCA and find novel therapies for this disease. The Pten gene in the biliary epithelial cells were genetically deleted using the Cre-loxp system. The pathologies were evaluated both macroscopically and histologically. The characteristics were further analyzed by immunohistochemistry (IHC), RT-PCR, cell culture, and RNAseq. Some features were compared to those in human eCCA samples. Further mechanistic studies utilized the conditional knockout of Trp53 and Aurora kinase A (Aurka) genes. Experimental therapy was tested using an Aurka inhibitor. We observed that genetic deletion of the Pten gene in the extrahepatic biliary epithelium and peri-ductal glands initiated sclerosing cholangitis-like lesions in mice, resulting in enlarged and distorted extrahepatic bile ducts in mice as early as one month old. Histologically, these lesions exhibited increased epithelial proliferation, inflammatory cell infiltration, and fibrosis. With aging, the lesions progressed from low-grade dysplasia to invasive carcinoma. Trp53 inactivation further accelerated the disease progression, potentially through downregulating senescence. Further mechanistic studies showed that both human and mouse eCCA showed high expressions of AURKA. Notably, the genetic deletion of Aurka completely eliminated Pten deficiency-induced extrahepatic bile duct lesions. Furthermore, pharmacological inhibition of Aurka alleviated disease progression. Pten deficiency in extrahepatic cholangiocytes and peribiliary glands led to a cholangitis-to-cholangiocarcinoma continuum through an Aurka-dependent manner. These findings offer new insights into preventive and therapeutic interventions for extrahepatic CCA. The aberrant PTEN-PI3K-AKT signaling pathway is commonly observed in human extrahepatic cholangiocarcinoma (eCCA), a disease with a poor prognosis. In our study, we developed a mouse model mimicking cholangitis to eCCA progression by conditionally deleting the Pten gene via Pdx1-Cre in epithelial cells and peribiliary glands of the extrahepatic biliary duct. The conditional Pten deletion in these cells led to cholangitis, which gradually advanced to dysplasia, ultimately resulting in eCCA. The loss of Pten heightened Akt signaling, cell proliferation, inflammation, fibrosis, DNA damage, epigenetic signaling, epithelial-mesenchymal transition (EMT), cell dysplasia, and cellular senescence. Genetic deletion or pharmacological inhibition of Aurka successfully halted the disease progression. This model shall be valuable for testing novel therapies and unraveling the mechanisms of eCCA tumorigenesis.

Neoadjuvant and adjuvant therapy for biliary tract cancer: Advances and limitations.

Biliary tract cancers (BTC), a rare and aggressive consortium of malignancies, consisting of intrahepatic cholangiocarcinoma, extrahepatic cholangiocarcinoma and gallbladder carcinoma. While most patients present with metastatic disease, a minority of patients with BTC are eligible for curative surgical resection at the time of presentation. However, these patients have poor 5-year overall survival rates and high rates of recurrence, necessitating the improvement of the neoadjuvant and adjuvant treatment of BTC. In this review, we assess the neoadjuvant and adjuvant clinical trials for the treatment of BTC and discuss the challenges and limitations of clinical trials, as well as future directions for the treatment of BTC.

Extrahepatic cholangiocarcinoma: Genomic variables associated with anatomical location and outcome.

554 Background: Genomic determinants of outcome in intrahepatic cholangiocarcinoma have become clear but remain ill-defined in extrahepatic cholangiocarcinoma (ECA). We aimed to clarify the genomic alterations that define ECA, analyze differences between perihilar (PCA) and distal (DCA) disease, and determine clinicopathologic and genomic factors associated with survival. Methods: Patients with EHC with tissue available for targeted next-generation sequencing at Memorial Sloan Kettering Cancer Center were identified. Differences between PCA and DCA were compared, stratified by disease extent and treatment. Associations between genomic alterations and clinicopathologic features and outcomes were analyzed. Univariable and then multivariable cox proportional hazards regression were used to compare survival, which was reported from operation in resected patients and from diagnosis in non-resected patients. Results: Two-hundred-twenty-four patients (n=127 PCA, n=97 DCA, 2006-2022) met inclusion criteria. Median survival was 29 months (IQR [25, 35]; 43 months [35, 48] resection, 17 months [13, 19] without). Compared to PCA, DCA was enriched in TP53mut (67 [69%] vs. 42 [33%]), Q&lt;0.01) and epigenetic pathway alterations (44 [45%] vs. 37 [29%], Q=0.041) and had more altered pathways (3 vs. 2, Q&lt;0.01). KRASmut was similar between PCA (46 [36%]) and DCA (36 [37%]); however, PCA was enriched in KRAS G12V (16 [13%] vs. 4 [4%]) and Q61H (11 [9%] vs. 3 [3%], P=0.002). No other clinicopathologic or genomic variables distinguished PCA from DCA (Table). MDM2mut occurred in 19/141 (13%) patients with nodal/metastatic disease compared to 1/83 (1%) patients with local disease ( Q=0.03), but conferred no survival disadvantage. In resected patients, survival was similar between PCA and DCA and no genomic alterations were associated with outcome. By contrast, in patients without surgery, CDKN2Adel (HR 2.59, 95% CI [1.48, 4.52]) and APCmut (HR 5.11, 95% CI [1.96, 13.3]) were associated with survival disadvantages. Lack of resection (HR 3.13, 95% CI [2.25, 4.36]), CDKN2Amut (HR 1.80 [95% CI 1.80, 2.68), and APCmut (HR 2.00 [95% CI 1.04, 3.87]) were associated with poor survival in the entire cohort. Conclusions: In this study, aside from a higher incidence of TP53mut in DCA and some differences in KRAS subtype alteration patterns, genomic alterations were comparable between PCA and DCA. CDKN2Amut and APCmut were associated with poor survival in all patients but no biomarkers provided significant prognostic information when tumors were resected. [Table: see text]

Efficacy and safety of surufatinib in biliary tract cancer: Preliminary results of a real-world study.

486 Background: When applied in the second-line treatment for biliary tract cancer (BTC) pts, surufatinib (a small-molecule inhibitor of VEGFR1-3, FGFR1 and CSF-1R) monotherapy has demonstrated moderate clinical efficacy and has demonstrated favorable tolerability and safety profiles. This study was to evaluate the efficacy and safety of surufatinib as a therapy for BTC in a real-world setting. In particular, pts who received resection for BTC with positive margins would be eligible for this study. This population indicates a poor prognosis, for their tumor environment is complex, which is an obstacle to R0 resection. However, no proper treatment for this population has been recommended yet. Methods: This is an ongoing single-arm, multi-center, open-label real-world study conducted in China. The study would enroll 200 pts with unresectable or surgical resection with positive margins BTC. Pts would receive surufatinib with or without combination as adjuvant (namely pts with positive margin after resection), first- or further-line therapy, at a proper dose (200-300mg) judged by physicians once per day in 28-day cycles. The primary endpoint is relapse-free survival (RFS) for pts whose primary lesions were resected, and progression-free survival (PFS) for those had evaluable lesions. If available, tumor assessments were performed every 2 cycles ± 7 days according to RECIST version 1.1. Results: By Sep 10, 2023, 56 eligible pts had been enrolled, of whom 16 (28.6%) were female. The median age was 64 (range: 39-81). 28 (50.0%), 24 (42.9%), and 4 (7.1%) pts received surufatinib as adjuvant, first-line, and above treatment, respectively. As to location, 23 cases were intrahepatic cholangiocarcinoma (ICC), and 33 cases were extrahepatic cholangiocarcinoma (ECC) or gallbladder cancer (GBC). With a median follow-up time of 9.5 (range: 1.1-20.3) mo, the global mRFS/mPFS was 10.4 (95% CI: 9.0-13.9) mo. The mRFS of pts who received surufatinib as adjuvant treatment was 11.3 (95% CI: 10.4-NA) mo, and mPFS of those who received surufatinib as systematic treatment was 9.0 (95% CI: 7.8-10.8) mo. Pts with ICC demonstrated an mRFS/mPFS of 10.4 (5.8-NA) mo, and those with ECC or GBC demonstrated 10.4 (9.5-NA) mo. The global mOS was 15.8 (12.4-NA) mo. Among those with primary lesion unresected (n=28), 2 pts (7.1%) achieved CR, 5 (17.9%) pts PR, 16 (57.1%) pts SD, and 5 (17.9%) pts suffered PD. The ORR was 25.0%, and DCR was 82.1%. No new safety signal was observed. Conclusions: Surufatinib exhibited promising efficacy and manageable toxicity on pts with BTC in the real-world setting. Clinical trial information: NCT05064852 .

Single-institutional analysis of radiotherapy and orthotopic liver transplant for patients with unresectable cholangiocarcinoma.

466 Background: There is increasing interest in effective strategies for locoregional therapy for cholangiocarcinoma, particularly given the evolving role of orthotopic liver transplant (OLT) for select patients. This single-institution retrospective study compares the clinical efficacy and toxicity of stereotactic body radiotherapy (SBRT), conventional fractionation chemoradiation (CRT), or SBRT as a bridge to OLT in patients with unresectable early stage and locally advanced cholangiocarcinoma. Methods: We reviewed a total of 31 patients from 2010 to 2023 with intrahepatic cholangiocarcinoma (ICC), extrahepatic cholangiocarcinoma (ECC), and perihilar cholangiocarcinoma who were treated with SBRT (n=22) or CRT (n=9). SBRT was delivered in 1-5 fractions, median dose of 40 Gy, and dose ranging from 16 Gy to 60 Gy. CRT was delivered in 13-28 fractions, median dose of 50.2 Gy, and dose ranging from 45 Gy to 52.5 Gy. Kaplan-Meier was used to analyze overall survival (OS), progression-free survival (PFS), and local control (LC). Acute and late G3+ toxicity was scored using CTCAE, version 5.0. Results: We identified 13 patients with ICC, 5 with ECC, and 13 with perihilar disease where SBRT or CRT was part of upfront definitive treatment. With a median follow-up time of 11 months, there was no statistical difference between SBRT vs. CRT for OS (median 21 vs. 22 months; p=0.36), PFS (median 14.2 vs. 11 months; p=0.09), and 1-year LC (73.2% vs. 66.7%; p=0.10). However, SBRT appeared to have lower proportions of acute grade 3+ (9.1% vs. 33.3%) and chronic grade 3+ toxicities (22.7% vs. 33.3%). Four patients with early stage perihilar or ICC underwent SBRT as successful bridge to transplant, with no evidence of disease progression at 5.4 months. An additional 2 out of 8 patients were removed from protocol due to disease progression and 2 others remain on protocol, awaiting OLT. Conclusions: In our series of unresectable cholangiocarcinoma, we found no difference in OS, PFS, and LC for patients treated with SBRT vs. CRT, although the former appeared to have lower toxicity and a trend towards improved PFS. Further research is needed to compare SBRT and CRT as definitive treatment or bridge to OLT for patients with unresectable cholangiocarcinoma.

Zanidatamab (zani) in previously treated HER2+ biliary tract cancer (BTC): Impact on patient-reported pain outcomes in the phase 2b HERIZON-BTC-01 study.

450 Background: The HER2 bispecific antibody zani showed rapid, durable responses and a manageable safety profile in patients with HER2+ BTC in the pivotal HERIZON-BTC-01 study. Here we report pain outcomes and opioid use for patients in this trial. Methods: HERIZON-BTC-01 (NCT04466891), an ongoing, open-label, Phase 2b study, is assessing zani (20 mg/kg IV Q2W) in patients with HER2+ (gene amplification and immunohistochemistry 2+ or 3+ [Cohort 1] and 0 or 1+ [Cohort 2]), locally advanced, unresectable or metastatic BTC (gallbladder cancer, intra-/extra-hepatic cholangiocarcinoma) who received prior gemcitabine-containing treatment (tx). Exploratory endpoints assessed at baseline (BL) and every 8 weeks included the Brief Pain Inventory short form, the visual analog scale (VAS), and analgesic opioid use. Results: Of the 80 patients with HER2+ BTC in Cohort 1 who were assessed for primary efficacy (median age 64 yrs; 56% female), 1 (1%) had complete response (CR), 32 (40%) partial response (PR), 22 (28%) stable disease (SD), and 24 (30%) progressive disease (PD); 1 patient was not evaluable. Responders (CR or PR) generally reported improved pain scores and less pain interference with activities of daily living. Patients with PD generally had worsening pain scores and pain interference by time of best on tx score (BONT) (Table). Overall, patients who responded to zani reported improved quality of life (VAS scores) vs BL. Fewer patients with CR (0.0%; n=1) and PR (3.1%; n=32) increased opioid use overall post-BL vs patients with SD (9.1%; n=22) or PD (34.8%; n=23). Conclusions: Patients with HER2+ BTC who responded to zani reported less pain and pain interference compared with BL, further supporting the development of zani as a tx option for these patients, with the goal of improving patient outcomes. Clinical trial information: NCT04466891 . [Table: see text]

Outcomes and prognostic factors of advanced biliary tract cancers in Saudi Arabia.

460 Background: Biliary tract cancers which include gallbladder adenocarcinoma, intrahepatic and extrahepatic cholangiocarcinoma are rare, and carry a poor prognosis. There is limited data on biliary tract cancers in the Saudi population. Methods: This single center retrospective study was conducted with data of eligible cases from the last 4 years. Survival, chemotherapy regimens, and variables such as neutrophil to lymphocyte ratio (NLR), and other potential prognostic variables were collected. Results: The study included 155 patients of which 75 had intrahepatic cholangiocarcinoma and 74 had gallbladder adenocarcinoma. The majority were females at 63% of patients. Overweight to obese patients represented 59% of the study cohort. The majority of patients (62%) had an ECOG performance status of 2 and below. Comprehensive genomic profiling was done to 20% of cholangiocarcinoma cases. Elevated CA19-9 tumor marker (&gt; 37 micromol/L) was found in 57% of patients. De novo metastatic disease affected 82% of patients. One third of patients (33%) were not fit for first line chemotherapy, and were given best supportive care. First line chemotherapy of platinum + gemcitabine was given to 53% of fit patients, followed by gemcitabine alone given to 38%, followed by 5-Fluorouracil chemotherapy given to 9% of patients. Very few patients lived for 12 months or more at 16%. There was a significant association between NLR and progression free survival (PFS) with median PFS being 3.5 months in the NLR &gt; 3 group (95% CI 1.2-6 months) versus median PFS of 9.8 months in the NLR &lt; 3 group (95% CI 7.5-12 months, p=0.019). Conclusions: Biliary tract cancers still carry a poor prognosis. NLR ratio of more than 3 was found to predict a low PFS.

Comparison of mucosal microbiomes from biliary tract among patients with extrahepatic cholangiocarcinoma, patients with chronic cholecystitis, and healthy controls.

550 Background: Cholangiocarcinoma (CCA) is a malignancy associated with a poor prognosis. Gut microbiome dysbiosis is considered to be related with multiple disease, including and cancer. However, relationship between mucosal microbiome dysbiosis and CCA remains unclear. In this study, we evaluated mucosal microbiome of patients with extrahepatic-CCA (EH-CCA) and compared it with patients with chronic cholecystitis (CC) and living liver donors who served as healthy control (HC), to understand the role of microbiome in development EH-CCA. Methods: A total of 18 patients with EH-CCA, 21 patients with CC, and 17 HC were included. During operation, swab sample were obtained from cancer tissue of patient with EH-CCA and from gallbladder in other participants, respectively. The bacterial 16S rRNA gene (V3/V4 region) was amplified using PCR and sequenced on the Illumina MiSeq platform. The QIIME 2 pipelines were used to analyze the raw data. Results: The median age were 71, 53, and 29 years for patients with EH-CCA, patients with CC, and HC, respectively. The mean number of operational taxonomic unit were significantly higher in the CCA (13,037 [SD 9,676]) compared to HC (5,045 [12,679]; p&lt;0.001). Among the sample from HC, the most abundant taxa at phylum level was Firmicutes (74.47%), followed by Bacteroidota (14.8%), and Proteobacteria accounted for only 2%. In the CC group, Firmicutes is most abundant (63.15%) phylum, followed by Proteobacteria (22.09%). In contrast, among the samples from CCA, Proteobacteria were the most common phylum (50.43%). Pairwise comparison of α-diversity measured by Chao1 index showed that richness was higher in samples from CC compared to other groups (vs HC, p=0.02; vs CCA, p&lt;0.001). In terms of α-diversity measured by Shannon index, samples from cancer have lower diversity compared to healthy controls ( p&lt;0.001), however, no significant differences were found between samples from cancer and CC ( p=0.1). The Principal Coordinate Analysis plot based on Bray-Curtis distance showed that all three groups formed significantly separate clusters (p=0.001). The linear discriminant analysis effect size showed that the most abundant taxa from samples from CCA were Enterobacter, Klebsiella, and Fusobacterium. In the samples from HC, Limosilactobacillus, Lachnospiraceae_NK4A136_group, and Faecalibacterium were most significant, while Lactobacillus and Pseudomonas were most abundant among the CC group. Conclusions: This study compared the mucosal microbiome from biliary tract among patients with CCA, patients with CC, and HC. All three groups showed significantly different microbiome profiles. In CCA sample, the proportion of Proteobacteria is high, and diversity were low, suggesting mucosal microbial dysbiosis. Further studies are needed to investigate the clinical implications of microbial dysbiosis in CCA.

Impact of next-generation sequencing in biliary tract cancer treatment.

560 Background: Incorporating molecular profiling in BTC treatment has increased. With this study, we aimed to analyze the impact of molecular profiles on the survival of patients with BTC. Methods: This is the retrospective analysis of patients with biopsy-proven biliary tract cancer at our comprehensive cancer center GI oncology clinic from 2018-2022. Only patients with continued care at Lombardi Comprehensive Cancer Center were included in the study. Results: Of 217 patients screened; 160 patients were included in the final analysis. The mean age of the cohort was 63 years, and the majority were females (55%). In the order of frequency, intrahepatic cholangiocarcinoma (77.5%) was the most common type of cancer followed by extrahepatic cholangiocarcinoma (15.6%), and carcinoma of the Gallbladder (6.9%). Molecular profiling was performed in 49.4% of the patients and actionable mutations for FDA approved treatments or clinical trial enrollment were found in 42 patients (26.3%) of the patients. The spectrum of actionable mutations in decreasing order of frequency was KRAS (n=11), FGFR2 (n=9), IDH-1 (n=8), Her-2neu (n=5), BRCA1/2 (n=5), &amp; PD-L1(n=4). Patients who underwent molecular profiling had significantly better survival (43±5 months vs. 25±4, p 0.013). Notably, patients with actionable mutations had even better survival as compared to the rest of the cohort (52±8 months vs. 26±7 months, p 0.019). Conclusions: BTC exhibits diverse genetic alterations. Patients who underwent molecular profiling as a part of the treatment plan had better survival. Identifying actionable mutations was associated with even better survival.