In fact, CUL4A gene has been reported to be amplified in various tumors such as hepatocellular carcinoma and breast cancer.[13,14] Furthermore, CUL4A overexpression was found in a variety of cancers, including malignant pleural mesothelioma and pituitary adenomas.[15,16] High CUL4A expression in intrahepatic cholangiocarcinoma,[17] lung cancer,[18] and colorectal cancer[19] correlated with poor prognosis and shorter overall survival (OS). This evidence concerns the gene CUL4A and intrahepatic cholangiocarcinoma.