Liver, bile ducts and gallbladder

Abstract

Immunohistochemistry (IHC) is an indispensable tool for pathological diagnosis of both neoplastic and non-neoplastic diseases of the liver and biliary tract. It has a wide spectrum of application ranging from pathogen detection to differentiation of primary from metastatic tumors. The focus of this chapter is to address applications regarding diagnosis and differential diagnosis of liver and biliary tract tumors. Commonly used markers or antibodies are listed in various tables detailing their staining patterns in benign, reactive and neoplastic conditions. Suggested panels of markers are provided to address specific diagnostic challenges such as distinguishing benign vs. malignant biliary proliferation and hepatocellular lesions, differentiating intrahepatic cholangiocarcinoma from extrhepatic cholangiocarinoma and metastatic adenocarcinomas from other organs. A process is defined utilizing an initial screening panel and subsequent confirmatory markers for unknown primary tumors in liver. Photomicrographs are provided to illustrate characteristic staining patterns.