Combination systemic therapies with immune checkpoint inhibitors in biliary tract cancer: effective but not enough?

Immune microenvironment of cholangiocarcinoma: Biological concepts and treatment strategies

Cholangiocarcinoma is characterized by a poor prognosis with limited treatment and management options. Chemotherapy using gemcitabine with cisplatin is the only available first-line therapy for patients with advanced cholangiocarcinoma, although it offers only palliation and yields a median survival of < 1 year. Recently there has been a resurgence of immunotherapy studies focusing on the ability of immunotherapy to inhibit cancer growth by impacting the tumor microenvironment. Based on the TOPAZ-1 trial, the US Food and Drug Administration has approved the combination of durvalumab and gemcitabine with cisplatin as the first-line treatment of cholangiocarcinoma. However, immunotherapy, like immune checkpoint blockade, is less effective in cholangiocarcinoma than in other types of cancer. Although several factors such as the exuberant desmoplastic reaction are responsible for cholangiocarcinoma treatment resistance, existing literature on cholangiocarcinoma cites the inflammatory and immunosuppressive environment as the most common factor. However, mechanisms activating the immunosuppressive tumor microenvironment contributing to cholangiocarcinoma drug resistance are complicated. Therefore, gaining insight into the interplay between immune cells and cholangiocarcinoma cells, as well as the natural development and evolution of the immune tumor microenvironment, would provide targets for therapeutic intervention and improve therapeutic efficacy by developing multimodal and multiagent immunotherapeutic approaches of cholangiocarcinoma to overcome the immunosuppressive tumor microenvironment. In this review, we discuss the role of the inflammatory microenvironment-cholangiocarcinoma crosstalk and reinforce the importance of inflammatory cells in the tumor microenvironment, thereby highlighting the explanatory and therapeutic shortcomings of immunotherapy monotherapy and proposing potentially promising combinational immunotherapeutic strategies.

Current Trends in Inpatient Care and In-Hospital Mortality of Cholangiocarcinoma in Germany: A Systematic Analysis between 2010 and 2019

Background: Cholangiocarcinoma (CCA) is a rare malignant disease of the biliary tract with an increasing incidence and a high mortality worldwide. Systematic data on epidemiological trends, treatment strategies, and in-hospital mortality of CCA in Germany are largely missing. However, the evaluation and careful interpretation of these data could help to further improve the treatment strategies and outcome of CCA patients in the future. Methods: Standardized hospital discharge data from the German Federal Statistical Office were used to evaluate epidemiological and clinical trends as well as the in-hospital mortality of CCA in Germany between 2010 and 2019. Results: A total of 154,515 hospitalized CCA cases were included into the analyses. The number of cases significantly increased over time (p < 0.001), with intrahepatic CCA (62.5%) being the most prevalent tumor localization. Overall, in-hospital mortality was 11.4% and remained unchanged over time. In-hospital mortality was significantly associated with patients’ age and tumor localization. The presence of clinical complications such as (sub)acute liver failure, acute respiratory distress syndrome (ARDS), or acute renal failure significantly increased in-hospital mortality up to 77.6%. In-hospital mortality was significantly lower among patients treated at high annual case volume centers. Finally, treatment strategies for CCA significantly changed over time and showed decisive differences with respect to the hospitals’ annual case volume. Conclusions: Our data provide a systematic overview on hospitalized CCA patients in Germany. We identified relevant clinical and epidemiological risk factors associated with an increased in-hospital mortality that could help to further improve framework conditions for the management of CCA patients in the future.