Snapshot A 35-year-old man with a history of primary sclerosing cholangitis presents with two weeks of jaundice, pruritus, and abdominal pain. He also has noticed that his urine is dark and stools are clay-colored. On physical exam, he has generalized jaundice and a palpable right upper quadrant mass. Lab studies are remarkable for elevated alkaline phosphatase, total bilirubin, alanine aminotransferase, aspartate aminotransferase, and CA 19-9. Magnetic resonance cholangiopancreatography reveals a contrast-enhancing intrahepatic lesion with rim enhancement. Introduction Most common malignancy of bile duct Caused by primary sclerosing cholangitis (MCC) thorotrast choledochal cyst Clonorchis sinensis (Chinese liver fluke) May be located intrahepatically at the junction of R/L hepatic ducts at the ampulla Presentation Symptoms jaundice pruritus abdominal pain clay-colored stool dark urine weight loss fever Physical exam palpable gallbladder Courvoisier's sign hepatomegaly Evaluation Labs tumor markers (AFP, CA 19-9, and CEA) Imaging often start with abdominal ultrasound or MRI/MRCP MRI, MRCP, or MDCT are most helpful for visualizing intrahepatic lesion EUS or ERCP are most helpful for visualizing extrahepatic lesions Treatment Surgery may be curative if no lymph node, vascular, or distant metastatic spread few patients present at early stage Chemotherapy and radiation may be used in adjuvant, neo-adjuvant, and/or palliative settings