Klatskin Tumor

The goal of this clinical trial is to learn about radiofrequency ablation in patients with unresectable bile duct cancer who receive systemic chemotherapy and bile duct stenting. The main questions it aims to answer are: * Does radiofrequency ablation of tumorous bile duct occlusion reduce risk of complications in these patients (eg stent dysfunction, delay of chemotherapy, infections etc)? * Is radiofrequency ablation safe in these patients? All participants will receive standard treatment with systemic chemotherapy and bile duct stenting. Researchers will compare two groups (one group will receive additional radiofrequency ablation, the other not).

The study will investigate whether liver transplantation provides increased survival, low side effects and good quality of life in patients with bile duct cancer where the tumor cannot be removed by normal surgery. Analyzes of blood and tissue samples from the tumor will be investigated to see if the analyzes can indicate who may have recurrence of the disease after liver transplantation. Furthermore, the effect of chemotherapy on normal liver and tumor tissues in the liver that are removed during transplantation will be investigated.

The objective of this study is to evaluate the efficacy of stereotactic body radiation therapy (SBRT) as additional treatment after standard chemotherapy regarding tumor local control, toxicity, progression-free survival (PFS), overall survival and quality of life. In addition, the objective is to explore the value of immunodynamics in peripheral blood for predicting PFS in patients undergoing chemotherapy.

Diagnosis of extrahepatic cholangiocarcinoma is challenging because the yield of imaging and tissue sampling is limited. Raman spectroscopy is an optical method based on the analysis of scattered monochromatic light. Raman spectroscopy is able to provide a molecular 'fingerprint' of the tissue to determine its type. The aim of this pilot study was to develop a methodology for in vivo Raman spectroscopy in bile ducts to improve the current diagnostic capabilities of extrahepatic cholangiocarcinoma.

This is multicentric, single-arm, observational, investigator-drive study investigating the efficacy of liver transplantation after successful downstaging/disease control of unresectable perihilar cholangiocarcinoma using chemotherapy +/- immunotherapy and stereotactic body radiation therapy (SBRT).