The Complete Loss of Tyrosine Kinase Receptors MET and RON Is a Poor Prognostic Factor in Patients with Extrahepatic Cholangiocarcinoma.

Although the survival of patients with cholangiocarcinoma has improved, the prognosis remains unfavorable. The overexpression of mesenchymal-epithelial transition factor (MET) and recepteur d'origine nantais (RON) has been considered to be indicative of a poor prognosis in some types of cancer. On the other hand, some studies have shown that the expression of MET and RON is a favorable prognostic factor in certain types of tumors.

Based on the immunohistochemical analysis of MET and RON, 290 patients who underwent resection for extrahepatic cholangiocarcinoma were divided into three groups: MET/RON-negative, -intermediate, and -positive. The associations between MET/RON expression and clinicopathological features, including prognosis, were analyzed.

MET/RON-negativity was associated with nodal metastasis and advanced pathological stage. The overall 5-year survival rates were significantly lower in the MET/RON-negative and MET/RON-positive groups than in the MET/RON-intermediate group (28.3%, 32.4% and 48.5%, respectively; p=0.01).

The complete loss of one or both MET and RON, as well as their overexpression, is a poor prognostic factor in patients with extrahepatic cholangiocarcinoma, probably due to the high rate of lymph-node metastasis.