Hepatocyte Nuclear Factor 1α-Mutated Hepatocellular Adenomas: An Atypical Presentation

Hepatocellular adenomas (HCAs) are rare benign monoclonal hepatic tumors that commonly occur in females (3–4 per 100,000 women) due to the use of oral contraceptives, its primary risk factor. Recently, HCAs have been classified into 4 distinct subtypes according to genotypic and phenotypic characteristics and clinical features: inflammatory HCA (40–50%), which are hypervascular with marked peliosis and a tendency to bleed; hepatocyte nuclear factor 1α (HNF1A)-mutated HCA (H-HCA, 30–40%) that are diffusely steatotic and rarely undergo malignant transformation; β-catenin activated HCA (10–15%), which frequently undergo malignant transformation and may seem hepatocellular carcinoma on imaging; and unclassified HCA (10–25%). In this study, we report the case of a 23-year-old female oral contraceptive user with H-HCA. Usually, H-HCA is considered to be nonsevere in most cases and often requires outpatient follow-up. However, in this case, the injury had substantially increased in volume and evolved with a major bleeding frame, which was an unusual finding for this subtype of adenoma. The therapeutic used for this patient was a laparoscopic left hepatic segmentectomy. Thus, the choice of treatment to be performed in a patient with H-HCA can depend on the tumor size (>5 cm), the outcome of previous bleeding, and the risk of bleeding recurrence.