Shin et al. integrated 59 methylation indicators from the DNA methylation study of eCCA tissues to verify and evaluate them in 77 bile specimens and finally found a five-gene panel composed of CCND2, CDH13, GRIN2B, RUNX3 and TWIST1 that can be used to distinguish CCA patients from benign groups in bile with 75.6% sensitivity and 100% specificity and which also can supple 39% of biliary cytological missed cases [9]. Here, GRIN2B is linked to cholangiocarcinoma.