Copyright ©The Author(s) 2021. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. May 21, 2021; 27(19): 2299-2311
Published online May 21, 2021. doi: 10.3748/wjg.v27.i19.2299
Clinical characteristics and outcomes of patients with hepatic angiomyolipoma: A literature review
Paul Calame, Gaëlle Tyrode, Delphine Weil Verhoeven, Sophie Félix, Anne Julia Klompenhouwer, Vincent Di Martino, Eric Delabrousse, Thierry Thévenot
Paul Calame, Eric Delabrousse, Department of Radiology, Jean Minjoz University Hospital, Besançon 25030, France
Gaëlle Tyrode, Delphine Weil Verhoeven, Vincent Di Martino, Thierry Thévenot, Department of Hepatology, Jean Minjoz University Hospital, Besançon 25030, France
Sophie Félix, Department of Pathology, Jean Minjoz University Hospital, Besançon 25000, France
Anne Julia Klompenhouwer, Department of Surgery, Erasmus University Medical Center, Rotterdam PO Box 2040, The Netherlands
Author contributions: Thévenot T designed the research; Thévenot T, Calame P, and Félix S analyzed the data; Thévenot T, Calame P and Tyrode G wrote the paper; Thévenot T and Calame P made critical revisions related to important content of the revised manuscript; Weil Verhoeven D, Klompenhouwer AJ, Di Martino V, Delabrousse E and Thévenot T provided the final approval of the version to be published.
Conflict-of-interest statement: No conflicts of interest exist.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See:
Corresponding author: Thierry Thévenot, PhD, Professor, Department of Hepatology, Jean Minjoz University Hospital, 3 Boulevard A. Fleming, Besançon 25030, France.
Received: October 27, 2020
Peer-review started: October 27, 2020
First decision: December 18, 2020
Revised: December 31, 2020
Accepted: March 18, 2021
Article in press: March 18, 2021
Published online: May 21, 2021

First reported in 1976, hepatic angiomyolipoma (HAML) is a rare mesenchymal liver tumor occurring mostly in middle-aged women. Diagnosis of the liver mass is often incidental on abdominal imaging due to the frequent absence of specific symptoms. Nearly 10% of HAMLs are associated with tuberous sclerosis complex. HAML contains variable proportions of blood vessels, smooth muscle cells and adipose tissue, which renders radiological diagnosis hazardous. Cells express positivity for HMB-45 and actin, thus these tumors are integrated into the group of perivascular epithelioid cell tumors. Typically, a HAML appears on magnetic resonance imaging (or computed tomography scan) as a hypervascular solid tumor with fatty areas and with washout, and can easily be misdiagnosed as other liver tumors, particularly hepatocellular carcinoma. The therapeutic strategy is not clearly defined, but surgical resection is indicated for symptomatic patients, for tumors showing an aggressive pattern (i.e., changes in size on imaging or high proliferation activity and atypical epithelioid pattern on liver biopsy), for large (> 5 cm) biopsy-proven HAML, and if doubts remain on imaging or histology. Conservative management may be justified in other conditions, since most cases follow a benign clinical course. In summary, the correct diagnosis of HAML is challenging on imaging and relies mainly on pathological findings.

Keywords: Angiomyolipoma, Liver, Tuberous sclerosis complex, Imaging, Pathology, Potentially malignant

Core Tip: Hepatic angiomyolipoma (HAML) is a rare, but not exceptional, mesenchymal liver tumor. HAML contains variable proportions of blood vessels, smooth muscle cells and adipose tissue, which renders its radiological diagnosis challenging. In most cases, this tumor follows a benign clinical course but more aggressive behavior may complicate management, which remains poorly codified. This review presents the main demographic and histological characteristics of HAML, summarizes reported cases of HAML with spontaneous rupture and aggressive behavior, and finally proposes a pragmatic algorithm for the management of HAML based on the most recent knowledge.