Methods of treating, and for selecting a chemotherapy regimen for treatment of cancer in a patient (FIG. 9). For example, a patient genetic sample from a bilary cancer such as cholangiocarcinoma is analyzed for a mutation in ERRFII and a chemotherapeutic agent is selected as a result of the analysis. If a mutation in ERRFII is present, treatment with an inhibitor of Epidermal Growth Factor Receptor (EGFR) is shown to have inhibitory effects on tumor growth. In this manner, the chemotherapy regimen is targeted to a given mutation in a patients cancer.
