Diagnosis and Treatment of Hepatic Angiomyolipoma in 26 Cases

Aim: To summarize the experience of the diagnosis and treatment of hepatic angiomyolipoma (HAML).

Methods: The clinical, imaging and pathological features, and treatment strategies of 26 patients with HAML treated at the authors' institute between October 1998 and January 2003 were retrospectively analyzed. All the patients received liver resection and were followed up till the study. Immunohistochemical assays were performed with a panel of antibodies.

Results: There was an obvious female predominance (21:5), and most of the patients (18/26) had no symptoms. Heterogeneous high echo was found in ultrasonography and punctiform or filiform vascular distribution pattern was found in color Doppler-sonography in most of the lesions (21/26). All of the 5 lesions further enhanced with Levovist showed early and prolonged enhancement. At contrast-enhanced spiral CT, the soft-tissue components of 24 lesions were markedly enhanced in the arterial phase and 18 lesions remained enhanced in the portal venous phase. MRI was performed in 9 patients, and showed hypointensity or hyperintensity on T1-weighted images and heterogeneous hyperintensity on T2-weighted images. Histopathologically, all lesions were composed of adipose tissues, smooth muscle and blood vessels with different proportions. Most lesions showed positive immunohistochemical staining for HMB45 (26/26), A103 (24/26) and SMA (24/26). All of the 26 patients showed a benign course with no sign of recurrence.

Conclusion: Preoperative radiological diagnosis of HAML is possible. The demonstration of intratumoral fat and central vessels is helpful in the diagnosis. HMB45, A103 and SMA are promising markers for pathologic diagnosis of HAML, and surgical resection is effective for the treatment of HAML.