IDH1 and infantile convulsions and choreoathetosis: Intrahepatic cholangiocarcinoma (iCCA), arising from the intrahepatic bile ducts, is enriched for alterations such as IDH1 mutations, FGFR2 fusions/rearrangements, BRAF V600E mutations, BAP1 loss, and microsatellite instability–high (MSI-H).