OBJECTIVE: Advanced biliary tract cancer (ABTC) is associated with a poor prognosis. Real-world data on the outcome of patients with ABTC undergoing sequential chemotherapies remain scarce, and little is known about treatment options beyond the established first- and second-line treatments with gemcitabine + cisplatin and FOLFOX. This study aimed to evaluate the outcome of patients with regard to different oncological therapies and to identify prognostic factors.
METHODS: From January 2010 until December 2019, 142 patients started palliative chemotherapy at our tertiary care liver center. Overall survival (OS) was calculated using Kaplan-Meier plots. Prognostic factors were evaluated using cox proportional-hazards.
RESULTS: Patients received a median number of 2 lines of chemotherapy. Median OS was 6.7, 15.2 and 18.2 months for patients who received 1, 2 and 3 lines of chemotherapy, respectively. Patients treated with FOLFIRINOX had a significantly extended OS of 23.8 months (log-rank test: p = 0.018). The univariate cox regression analysis identified several clinical parameters associated with survival (e.g. albumin, bilirubin, carcinoembryonic antigen, carbohydrate antigen 19-9 levels).
CONCLUSIONS: Our study provides real-world data on the prognosis of ABTC including survival times for patients receiving third and later lines of chemotherapy.
BACKGROUND: Real-world data depicting the outcome of patients with advanced biliary tract cancer outside the framework of controlled trials remain rare despite being extremely important for clinical decision-making. This study therefore provides important real-world data on the established first- and second-line treatments with gemcitabine + cisplatin and FOLFOX, as well as on other chemotherapy regimens or later lines of chemotherapy. It further demonstrates that the use of FOLFIRINOX is associated with promising survival and that there is an association between various clinical parameters such as pre-therapeutic albumin, bilirubin or carbohydrate antigen 19-9 levels and survival.

Biliary tract cancers (BTCs) are aggressive epithelial malignancies that can arise at any point of the biliary tree. Albeit rare, their incidence and mortality rates have been rising steadily over the past 40 years, highlighting the need to improve current diagnostic and therapeutic strategies. BTCs show high inter- and intra-tumour heterogeneity both at the morphological and molecular level. Such complex heterogeneity poses a substantial obstacle to effective interventions. It is widely accepted that the observed heterogeneity may be the result of a complex interplay of different elements, including risk factors, distinct molecular alterations and multiple potential cells of origin. The use of genetic lineage tracing systems in experimental models has identified cholangiocytes, hepatocytes and/or progenitor-like cells as the cells of origin of BTCs. Genomic evidence in support of the distinct cell of origin hypotheses is growing. In this review, we focus on recent advances in the histopathological subtyping of BTCs, discuss current genomic evidence and outline lineage tracing studies that have contributed to the current knowledge surrounding the cell of origin of these tumours.

BACKGROUND: The diagnosis of biliary tract cancer (BTC) is challenging in clinical practice. We performed a prospective study to evaluate the value of plasma copy number variation (CNV) assays in diagnosing BTC.
METHODS: 47 treatment-naïve patients with suspicious biliary lesions were recruited. Plasma samples were collected at admission. Cell-free DNA was analyzed by low coverage whole genome sequencing, followed by CNV analyses via a customized bioinformatics workflow, namely the ultrasensitive chromosomal aneuploidy detector.
RESULTS: 29 patients were pathologically diagnosed as BTC, including 8 gallbladder cancers (GBCs) and 21 cholangiocarcinomas (CCs). Cancer patients had more CNV signals as compared with benign patients (26/29 vs. 2/18, P < 0.001). The most frequent copy number gains were chr3q (7/29) and chr8q (6/29). The most frequent copy number losses were chr7p (6/29), chr17p (6/29), and chr19p (6/29). The sensitivity and specificity of plasma CNV assays in diagnosing BTC were 89.7% and 88.9%, respectively. For CA 19-9 (cutoff: 37 U/ml), the sensitivity was 58.6% and the specificity was 72.2%. The diagnostic accuracy of CNV assays significantly outperformed CA 19-9 (AUC 0.91 vs. 0.62, P = 0.004). Compared with CA 19-9 alone, the adding of CNV profiles to CA 19-9 increased the sensitivity in diagnosing GBC (75.0% vs. 25.0%) and CC (100% vs. 52.4%). Higher CNV burden was also associated with decreased overall survival (Hazard ratio = 4.32, 95% CI 2.06-9.08, P = 0.033).
CONCLUSIONS: Our results suggest that BTC harbors rich plasma CNV signals, and their assays might be useful for diagnosing BTC.