Identification of New Biomarkers for Patients With Cholangiocarcinoma and Gallbladder Cancer

This study is collecting blood samples and tissue from patients with biliary tract cancers (cancers of the bile ducts or gallbladder) to search for new biological markers (biomarkers) that could help diagnose these cancers earlier or guide treatment decisions. **You may be eligible if:** - You have been diagnosed with cholangiocarcinoma (bile duct cancer) or gallbladder cancer, confirmed by pathology or imaging - You are being referred or treated for biliary tract cancer - You are able to give informed consent - Prior treatment with chemotherapy or radiation is acceptable **You may NOT be eligible if:** - There are no specific exclusion criteria listed for this study Talk to your doctor to see if this trial is right for you.