S3365 Role of Cholangioscopy in the Work-Up of Bile Duct Lesions With Elevated CA 19-9 and AFP

Introduction: Endoscopic retrograde cholangiopancreatography (ERCP) with per-oral single-operator cholangioscopy (PSOC) is invaluable in evaluating pancreatic and biliary diseases. This study explores a unique application of PSOC. Case Description/Methods: A 67-year-old man with compensated cirrhosis and hepatitis C virus-HIV co-infection presented with abdominal pain and jaundice. Magnetic resonance imaging showed cirrhosis, capsular retraction of the right lateral lobe, right intrahepatic biliary dilation, and non-dilated extrahepatic bile duct. There was enhancement in segment 5 extending to segment 4B, with nodularity near the main portal vein. AFP and CA 19-9 levels were elevated. ERCP with PSOC revealed a stricture and nodular mass at the hilar confluence. Biopsies revealed atypical cells with hepatoid differentiation. Immunohistochemical stains were Hep-par positive and CK7 negative consistent with hepatocellular carcinoma (HCC). Discussion: Biliary strictures are common in cholangiocarcinoma (CCA) but are rare with HCC. Bile duct invasion (BDI) by HCC can be misdiagnosed as cholecystitis, cholangitis, choledocholithiasis, or CCA. Cirrhosis is often present in HCC with BDI, and on PSOC, a non-circumferential stricture and a friable luminal mass with villiform surface and increased vascularity is usually seen. The lesion is often located at the hilar confluence and can be covered with tumor capsule, so scraping the lesion improves tissue diagnosis. Literature on PSOC diagnosis of HCC has mainly commented on AFP levels. At least 1 case of combined HCC-CCA on PSOC-directed biopsies has been reported. In our patient, elevation of both CA 19-9 and AFP levels with abnormal biliary imaging presented a conundrum. PSOC-directed biopsies established the correct diagnosis. To the best of our knowledge, this entity has not been previously recognized. CA 19-9 levels could have been elevated due to biliary obstruction or HCC.