Clinical meaning
Cholangiocarcinoma arises from malignant transformation of cholangiocytes lining the intra- or extrahepatic bile ducts. Chronic inflammation from conditions such as primary sclerosing cholangitis (PSC), liver fluke infection, or hepatolithiasis drives repeated cycles of epithelial injury and repair, promoting oncogenic mutations (TP53, KRAS, IDH1/2). The tumor causes progressive biliary obstruction, leading to conjugated hyperbilirubinemia, cholestasis, and eventual hepatic dysfunction. Perihilar (Klatskin) tumors are the most common subtype.
Diagnosis & workup
Diagnostics & workup: - MRCP or ERCP to visualize biliary tree obstruction and stricture location - CA 19-9 and CEA tumor markers (elevated in ~60% of cases) - Liver function panel showing cholestatic pattern (elevated ALP, GGT, direct bilirubin) - CT abdomen with contrast for staging and vascular involvement - Brush cytology or biopsy via ERCP for tissue diagnosis - PET-CT for distant metastasis evaluation
Risk factors: - Primary sclerosing cholangitis (PSC) - Liver fluke infection (Opisthorchis, Clonorchis) - Hepatolithiasis and choledochal cysts - Chronic hepatitis B or C infection - Cirrhosis from any cause - Inflammatory bowel disease (especially ulcerative colitis) - Thorotrast exposure - Age > 65 years