EGFR and intrahepatic cholangiocarcinoma: Activation mutations, rather than amplification, of genes such as Kirsten rat sarcoma viral oncogene homolog (KRAS), isocitrate dehydrogenase 1 (IDH1), IDH2, B-Raf proto-oncogene, serine/threonine kinase (BRAF), and epidermal growth factor receptor (EGFR), have been shown to have a potential impact on the prognosis of intrahepatic cholangiocarcinoma (iCCA) [2].