Lecture : Hepatocellular adenomas (HCA) are a rare benign liver neoplasm mainly observed in young women taking oral contraceptives (OC). Unlike other benign liver diseases such as hemangiomas and focal nodular hyperplasia for which the risk of surgery is higher than the risk of spontaneous complications, there is still a surgical indication for HCA because of the risk of bleeding and malignancy. Major progress has been made in the last decade in the clinical, radiological and histological understanding of this disease. HCA is no longer considered to be a single entity but is now divided into 3 radiological (inflammatory, HNF1A and classic) and 5 main histological (HNF1A, inflammatory, β catenin, sonic hedgehog and unclassified) subtypes with different risks of complications. The risk factors for complications are well known and include HCA > 5 cm whatever the subtype (risk of bleeding and malignancy) and male gender whatever the size (risk of malignancy). Inflammatory and sonic hedgehogs are at risk of bleeding and the risk of malignancy is increased in β catenin HCA with a mutation in exon 3 and unclassified. HNF1A (steatotic HCA) have a low risk of complications.