[68Ga]Ga-FAPI-46 Positron Emission Tomography (PET) Scan to Improve the Imaging of Pancreatic and Bile Duct Cancer

The goal of this clinical trial is to evaluate the clinical use of \[68Ga\]Ga-FAPI-46 PET (positron emission tomography)/CT (computed tomography) imaging in patients with pancreatic or bile duct cancer. The study consists of three parts and patients can only participate in one part of the study. The main questions the study aims to answer are: * In part A: What is the best timing and scanprotocol of a \[68Ga\]Ga-FAPI-46 PET/CT scan? * In part B: Are the results of the simplified scan protocol repeatable? * In part C: What is the accuracy of \[68Ga\]Ga-FAPI-46 PET/CT to detect pancreatic cancer and is it able to detect the effect of chemotherapy on pancreatic cancer lesions? Participants in this study will be asked to undergo the following: * In part A: participants will undergo 1 \[68Ga\]Ga-FAPI-46 PET/CT scan and will have 2 venous canullas and 1 arterial cannula placed. * In part B: participants will undergo 2 \[68Ga\]Ga-FAPI-46 PET/CT scans and will have a venous cannula placed for each scan. * In part C: participants will undergo 2 \[68Ga\]Ga-FAPI-46 PET/CT scans and will have a venous cannula placed for each scan.