EGFR and cholangiocarcinoma: Among potential therapeutic targets, several studies have revealed overexpression of epidermal growth factor receptor (EGFR) or human epidermal growth factor receptor 2 (HER2) protein, amplification, and mutation of these genes (Ito et al, 2001; Aishima et al, 2002; Ukita et al, 2002; Altimari et al, 2003; Gwak et al, 2005; Nakazawa et al, 2005; Leone et al, 2006) as well as overexpression of vascular endothelial growth factor (VEGF) protein (Hida et al, 1999; Tang et al, 2006) in cholangiocarcinoma.