Patient No. 1, a 62-year-old male with poorly differentiated perihilar CCA accompanied by Her2 protein overexpressed in >90% tumor cells, was enrolled into this study when 2 metastatic lesions in his hepatic hilum were detected by positron emission tomography-computed tomography (PET-CT) 12 months after the radical surgery. The gene discussed is ERBB2; the disease is cholangiocarcinoma.