Management of hepatic angiomyolipoma: A systematic review

Abstract

Hepatic Angiomyolipoma (HAML) is a rare mesenchymal liver tumour assumed to be predominantly benign, although incidental cases with malignant behaviour such as invasive growth, recurrence after resection and metastases have been reported. The aim of this systematic review was to assess the biological behaviour, estimate the risk of HAML related mortality and recommend on a justifiable management strategy. We performed a systematic literature search in Embase, Medline, Web-of-Science, Scopus, Pubmed Publisher, Cochrane and Google Scholar. We included all articles published from inception until March 2016 which reported on follow-up of various treatment strategies. We included 18 articles reporting on 292 patients. Male:female ratio was estimated at 1:3 with gender not reported in 31 cases. Of 292 patients 247 were treated with surgery, including one liver transplant, seven with chemotherapy or Sirolimus, three with embolization, and 35 conservatively. Recurrence after resection was described in 6/247 (2.4%) with pathologically proven HAML resulting in metastases and death in 2/247 (mortality rate 0.8%). Progression was described in 6/35 patients treated conservatively (21.4%). Two of 12 patients with malignant behaviour of HAML had an epithelioid-type HAML, of the remaining 10 histological subtype was undefined. With a risk estimate of 0.8% in surgically treated patients HAML related mortality is very low. Biopsy is indicated when imaging is inconclusive. In case of certain HAML diagnosis on imaging conservative management with annual imaging is justified. Resection should be considered in case of symptoms, inconclusive biopsy or growth in follow-up. K E Y W O R D SHepatic angiomyolipoma, malignant, management, review

Hepatic angiomyolipoma: mutation analysis and immunohistochemical pitfalls in diagnosis

“…AMLs also closely resemble HCC on imaging . The distinction is important, as the vast majority of AMLs behave in a benign fashion, and reports of recurrence or metastasis are rare …”

“…7,8 The distinction is important, as the vast majority of AMLs behave in a benign fashion, and reports of recurrence or metastasis are rare. [9][10][11][12][13][14] We have observed anecdotal cases of AML which were mistaken for hepatocellular neoplasms on haematoxylin and eosin (H&E) stain, and in which immunohistochemical markers such as liver fatty acid binding protein (LFABP) and glutamine synthetase (GS) had been obtained. These cases showed negative LFABP leading to the suspicion of hepatocyte nuclear factor alpha (HNF1a)-inactivated HCA, while diffuse GS staining has led to suspicion of b-catenin-activated HCA/HCC.…”

Hepatic angiomyolipoma detected using computed tomography

“…A ‘typical presentation’ on CT or magnetic resonance imaging is the presence of fatty areas and solid tissue components. However, in practice, fat is found to be unreliable as some HCCs also contain fat . The early venous drainage to the hepatic vein, peripheral decreasing enhancement rim and absence of tumour capsules are helpful in differentiating angiomyolipoma from HCC .…”

“…However, in practice, fat is found to be unreliable as some HCCs also contain fat . The early venous drainage to the hepatic vein, peripheral decreasing enhancement rim and absence of tumour capsules are helpful in differentiating angiomyolipoma from HCC . Owing to the recent advancements in radiological imaging devices, including multidetector CT, this typical early venous drainage, which was initially assessed using angiography, can now be identified using contrast‐enhanced CT.…”

Hepatic angiomyolipoma presenting as an arterially enhancing liver lesion

“…There is no current consensus regarding the optimal management approach for HAML, with features of malignant behaviour such as recurrence after resection and metastasis increasingly reported of these tumours . When imaging prove inconclusive, biopsy can be performed and resection should be indicated when biopsy provides an uncertain diagnosis or shows high proliferation activity, or when there is development of symptoms or aggressive growth . Otherwise for certain HAML diagnosis, conservative monitoring is justified.…”