As rearrangement of ROS1 gene was reported in cholangiocarcinoma recently [17, 22], and ROS1 inhibitors such as crizotinib or foretinib (GSK1363089) have shown remarkable activity in ROS1-driven tumors [8, 16, 23], the actual incidence of protein expression and gene rearrangements of ROS1, as well as its clinical significance in BTC, were pursued in the present study. Here, ROS1 is linked to cholangiocarcinoma.