The study found that use of DPP4 inhibitors, compared with other second- or third-line glucose-lowering drugs, was associated with a 77% increase in the risk of cholangiocarcinoma (HR 1.77 [95% CI 1.04, 3.01]), although the analysis only included 27 DPP4 inhibitor-exposed events. This evidence concerns the gene DPP4 and cholangiocarcinoma.