The Role of Histology in Hepatocellular and Cholangiocarcinoma

Abstract

Liver histology retains an essential role in the diagnosis and management of patients with primary liver tumour. It is complemented but cannot be replaced by molecular techniques. The role of liver biopsy differs depending on the clinical context. Liver biopsy has been almost entirely replaced by imaging, for the diagnosis of early hepatocellular carcinoma in patients with advanced stage chronic liver disease (cirrhosis), although a return to histological diagnosis has been advocated. Liver biopsy retains a critical role in the histological diagnosis of hepatocellular adenoma and hepatocellular carcinoma arising in patients with early stage chronic liver disease or normal/near-normal liver and in the diagnosis of intrahepatic cholangiocarcinoma. The term “hepatocellular neoplasm of uncertain malignant potential” has been proposed in those instances in which it is not possible to differentiate between hepatocellular adenoma and hepatocellular carcinoma. The diagnosis of combined (or mixed) hepatocellular-cholangiocarcinoma remains challenging particularly on liver biopsy. The differential diagnosis between intrahepatic cholangiocarcinoma and metastatic adenocarcinoma requires often close clinico-pathological correlation and should not be based exclusively on immunohistochemistry. Intraoperative histological examination is critical to guide surgical intervention. It is routinely used to assess clearance of resection margins particularly for hilar cholangiocarcinoma. Histological examination of surgically resected specimens is essential to confirm the preoperative diagnosis and assess the effect of previous therapies and for prognosis in both hepatocellular and cholangiocellular tumours.