HNF1A and hepatocellular adenoma: Adenomas are currently categorized into seven distinct subtypes: inflammatory; HNF-1α-inactivated; β-catenin-activated (also called β-catenin mutated, caused by a mutation of exon 3); weak β-catenin-activated (caused by a mutation of exon 7/8); sonic hedgehog pathway activated; and unclassified hepatocellular adenoma; as well as two subtypes with overlapping features of the inflammatory and β-catenin-activated subtypes [115,135].