New Prospective Expanded German Registry of Incidental Gallbladder Carcinoma (PERSUASION)- a Permanent Platform Including All Kind of Biliary Tract Cancers (BTC)

Inclusion Criteria: * Known biliary-tract cancer including intrahepatic-, extrahepatic- and gallbladder carcinomas * age ≥18 years * signed informed consent form * planned for (or recently started - i.e. within the last 21 days)) neoadjuvant, adjuvant or 1st line therapy Exclusion Criteria: * Patients who are unable to consent because they do not understand the nature, significance and implications of the registry and therefore cannot form a rational intention * Patient under 18 years of age * Patient's inability to complete QoL questionnaire or answer the questions. * Second-line or further palliative therapies if the patient's first-line therapy was not documented within the study.