Although previousstudies also identified transcriptionally CCA-like HCC (Oishi et al., 2012; Seoket al., 2012; Woo et al., 2010),our results identify IDH and FGFR2 perturbationsas associated drivers linked to methylation, miRNA, and copy number similarities.Together, these findings highlight the uniqueness ofIDH-mutant-driven cancers and the importance of defective chromatinregulation in the pathogenesis of CCA. The gene discussed is IDH2; the disease is cholangiocarcinoma.