Pathological Classification and Surgical Approach to Hepatocellular Adenomas

Abstract

Hepatocellular adenomas (HCAs) are a rare benign liver neoplasm mainly observed in young women taking oral contraceptives (OC) (Baum et al., Lancet 2:926-929, 1973; Rooks et al., JAMA 242:644-648, 1979; Carrasco et al., N Engl J Med 310:1120-1121, 1984; Rosenberg, Contraception 43:643-652, 1991; Heinemann et al., Eur J Contracept Reprod Health Care 3:194-200, 1998). Unlike other benign liver diseases such as hemangiomas and focal nodular hyperplasia (FNH) for which the risk of surgery is higher than the risk of spontaneous complications (Schnelldorfer et al., J Am Coll Surg 211(6):724-730, 2010), there is still a surgical indication for HCA because of the risk of bleeding and malignancy (Cho et al., Ann Surg Oncol 15:2795-2803, 2008; Dokmak et al., Gastroenterology 137:1698-1705, 2009; Deneve et al., Ann Surg Oncol 16:640-648, 2009). 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 three radiological (inflammatory, steatotic, and classic) and five histological (inflammatory, HNF1A, b catenin, sonic hedgehog, and unclassified, HNF1A, inflammatory, Β-catenin, sonic hedgehog, and unclassified) subtypes with different risks of complications (Nault et al., Gastroenterology 152(4):880-894, 2017). 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). However, HNF1A (steatotic HCA) has a low risk of complications, and the risk of malignancy is increased in Β-catenin HCA with a mutation in exon 3 (Dokmak et al., Gastroenterology 137:1698-1705, 2009; Nault et al., Gastroenterology 152(4):880-894, 2017).