Furthermore, the prognostic significance of MUC1 was reconfirmed in the ICC subgroups with low recurrent risk (Figure S1), such as CA199 level <37 U/ml, Tumor size ≤5 cm, without lymphatic metastasis, without vascular invasion and TNM stage I 29,40. The gene discussed is MUC1; the disease is intrahepatic cholangiocarcinoma.