The Effect of [18F] F-FAPI PET-CT on Management in Patients With Proximal Cholangiocarcinoma

Background Bile duct cancer (cholangiocarcinoma) represents the second most common type of hepatobiliary cancer worldwide with an incidence of 0.35 to 2 per 100.000 annually. Currently, surgical resection is the only curative option. However, patients are not eligible for surgery if the tumor cannot be resected or the cancer has spread. For this group of patients, palliative chemotherapy is the most suited treatment option. To find out if a patient is suited for surgery, CT and MRI are performed. These imaging techniques, however, struggle to correctly identify small cancer spreads that are smaller than 1 cm. Therefore, cancer that has already spread can be found during surgery. In these cases, the tumor cannot be removed and the surgery therefore has not been of any benefit for the patient. These surgeries could be avoided by implementing a diagnostic tool with significantly higher accuracy than those currently used. Single center studies have shown that fibroblast activation protein inhibitor (FAPI) PET-CT is a very promising technique for determining metastases in tumors with prominent desmoplastic reactions, like cholangiocarcinoma. The investigators predict that implementation of preoperative FAPI PET-CT could prevent futile surgery for at least half of patients in whom intra-operative metastasized disease is found using the current work-up. Patient population Patients ≥18 years with potentially curable proximal cholangiocarcinoma (perihilar, intrahepatic and gall bladder cholangiocarcinoma) who are planned to undergo surgery based on imaging using CT thorax/abdomen and MRI of the upper abdomen. Exclusion criteria are previous abdominal surgery or chemotherapy, known pregnancy or lactation and indication for FDG PET-CT. Participation in this study Participation would mean to undergo FAPI PET-CT prior to the scheduled surgery. This will take up about half a day of the participant's time. Afterwards, participants receive questionnaires about quality of life