Tumor-Like Lesions of the Liver and Intrahepatic Bile Duct

Focal nodular hyperplasia (FNH) was first reported by Edmondson in 1958, and the first case of FNH in China was reported in 1991 [1, 2]. FNH is a common benign tumor-like lesion with incidence rates of 0.6~3% in populations [3] and accounts for 8% among primary liver tumor [4] ranking the second common tumor or tumor-like lesion after liver hemangioma. Clonal feature detection of FNH showed that 50–100% of the liver cells were polyclonal and characteristic genetic mutations have not been found in FNH while vessel maturation-related gene (ANGPT1 and ANGPT2) changes were found in FNH. Compared with normal liver tissue, liver cirrhosis, and other hepatic tumors, the levels of ANGPT1 and ANGPT2 in FNH increased indicating vessel changes play a role in the formation of FNH, while others demonstrated the activation of β-catenin pathway without mutation of β-catenin [5].