Balitzer et al. [78] reported that results of immunohistochemical staining for CK19, SALL4, CD56, CD117, and epithelial membrane antigen (EMA) as well as the molecular features based on next-generation sequencing results were similar between ICC and CoCC; they argued that CoCC should be classified as a subtype of ICC. This evidence concerns the gene MUC1 and intrahepatic cholangiocarcinoma.