Focal Nodular Hyperplasia and Hepatic Adenoma: Epidemiology and Pathology

Focal nodular hyperplasia (FNH) and hepatic adenoma (HA) represent the most frequent non-vascular benign liver tumors. They are often asymptomatic. The widespread use of high-resolution imaging modalities leads to an increase of incidental detection of FNH and HA. Physicians are thus increasingly confronted with these formerly rarely recognized conditions, stressing the need for concise but adequate information on the optimal clinical strategies for these patients. FNH is the most common non-vascular benign tumor of the liver. It probably arises as a polyclonal, hyperplastic response to a locally disturbed blood flow. It is typically found in asymptomatic women. Histologically, FNH can be described as a focal form of cirrhosis. Complications of FNH are extremely rare and surgical resection is generally not advised. HA is a rare monoclonal, but benign liver tumor primarily found in young females using estrogen-containing contraceptives. Although its exact etiology is unknown, a direct link between sex steroid exposure and the uncontrolled hepatocellular growth is suspected. Complications of HA are spontaneous bleeding and malignant transformation. Withdrawal of estrogen treatment and excision of large tumors Published online: April 1, 2010 Prof. Dr. Ulrich Beuers Department of Gastroenterology and Hepatology, G4-213 Academic Medical Center, University of Amsterdam PO Box 22700, NL–1100 DE Amsterdam (The Netherlands) Tel. +31 20 56 62 422, Fax +31 20 69 17 033, E-Mail u.h.beuers @ amc.uva.nl © 2010 S. Karger AG, Basel 0253–4886/10/0271–0024$26.00/0 Accessible online at: www.karger.com/dsu D ow nl oa de d by : 54 .7 0. 40 .1 1 11 /2 0/ 20 17 1 0: 51 :4 6 P M