Can Thymidine Phosphorylase Be a Predictive Marker for Gemcitabine and Doxifluridine Combination Chemotherapy in Cholangiocarcinoma?: Case Series

Unresectable cholangiocarcinoma is poorly responded to chemotherapy, especially for the case refractory to gemcitabine and cisplatin. Here, we tested whether high expression of thymidine phosphorylase (TP) can be a predictive biomarker for the indicator for gemcitabine and doxifluridine combination chemotherapy in the cholangiocarcinoma refractory to gemcitabine and cisplatin. Immunohistochemical staining for TP was performed with a biopsy specimen. We accepted the result as positive when more than 10% of cancer cells were stained with moderate intensity. Here, we report 2 cases of TP-positive cholangiocarcinoma well controlled with gemcitabine and doxifluridine combination chemotherapy, which had been refractory to the first line treatment with gemcitabine and cisplatin combination chemotherapy.