For example, in our cohort, IDH1 alterations were mainly enriched in ICC patients (ICC vs. ECC vs. GBC, 2.8% vs. 1.5%% vs. 0.9%%), which was in concordance with a previous finding that IDH1 alterations have been reported in approximately 13% of ICC patients but were rare in other histological subtypes of BTC (57). The gene discussed is IDH1; the disease is intrahepatic cholangiocarcinoma.