Singular studies conducted on different subtypes of CC (invasive iCC, MF-CC; extrahepatic CC) [47,76,82,145,164], as well as extensive meta-analysis (3425 patients) confirmed that increased MUC1 expression (including that of its more sialylated glycoform) was significantly associated with poor OS in patients with GI tract carcinomas, including CC [in fixed-effect model (FEM): HR = 2.52, 95%CI: 1.42–4.49, PFEM = 0.252; and at random-effect model (REM): HR = 2.34, 95%CI: 1.30–4.22, PREM = 0.244] [161]. Here, MUC1 is linked to cholangiocarcinoma.