Hepatocellular adenoma (HA) is a rare benign liver tumor with increasing incidence affecting young women. In the last years, much has changed in diagnosis, classification, and treatment, due to the identification of different molecular subtypes. With the evolving knowledge, especially on molecular characteristics of the disease, we are far from a consensus of how to deal with such a multifaceted benign disease METHODS: In the last 20 years, we have treated 134 patients with HA with a mean age of 28 years, being 126 women. Fifty patients had a history of abdominal pain and 13 patients had an acute episode of pain due to rupture and bleeding. Until 2009, adenomas larger than 4 cm in diameter were resected, regardless of gender. From 2010 to 2016, only adenomas larger than 5 cm were referred for surgical treatment. Since 2016, resection was indicated in all female patients with non-steatotic adenomas larger than 5 cm and all adenomas in men.
One hundred twenty-four patients were submitted to resection, being in 21 major resections. Since 2010, 74% of resections were done laparoscopically. Patients with ruptured adenomas were treated with transarterial embolization. Morbidity rate was 8.1% with no mortality. Authors discuss point-by-point all the aspects and presentations of the disease and the best approach. We proposed a therapeutic guideline based on the best available evidence and in our experience.
Due to the complexity of the disease, the treatment of HA is one the best examples of an individualized approach.

Rapid advances in molecular and anatomic pathology have greatly improved our understanding of hepatocellular adenomas. Principle among them is a clinically relevant, histology-based classification that identifies hepatic adenomas at greatest risk for malignant transformation. This new classification system has led to general consensus on the major subtypes of hepatic adenomas. However, controversy remains regarding how to incorporate less common types of hepatic adenomas into the classification system and how to incorporate adenoma subtyping into clinical care. This article provides an in-depth review of how adenomas are classified, with a focus on the current rationale, the consensus, and controversies.