By using the area under of the curve (AUC) as a determinant of overall performance of the test, we found that biliary CEACAM6 could differentiate any cholangiocarcinoma (AUC = 0.738) or extrahepatic cholangiocarcinoma (AUC = 0.791) from benign disease. Here, CEACAM6 is linked to cholangiocarcinoma.