A COMPREHENSIVE BIOMARKER EVALUATION IN BILIARY TRACT CANCER

Inclusion Criteria: 1. Written informed consent for the use of clinical data and tissue samples is available. (The use of data and samples without consent is only possible if exemption is granted by the corresponding Institutional Review Board - IRB). 2. Histologically confirmed diagnosis of biliary tract cancer (including gallbladder carcinoma \[GBC\] or cholangiocarcinoma \[CCA\]), regardless of disease stage. 3. Diagnosis must have been established within the last 15 years prior to Study initiation. 4. Availability of archival formalin-fixed paraffin-embedded (FFPE) tumor tissue sample, collected prior to Study inclusion at any disease stage (e.g., during surgery or in the advanced setting). For patients with de novo metastatic disease or early stage primary tumors undergoing surgery, the tissue must have been obtained before the initiation of any systemic therapy (e.g. chemotherapy) or radiotherapy. For patients with recurrent disease undergoing a new biopsy, previous treatments are allowed. 5. Availability and accessibility of basic clinical information and survival data on medical records. Exclusion Criteria: 1. Unavailability or inadequate quality (e.g., insufficient tumor content, degraded tissue) of archival FFPE tumor tissue samples for the planned immunohistochemical analysis. 2. Missing or incomplete basic clinical and/or survival data in the medical record.