Conventional Ultrasound and Contrast-Enhanced Ultrasound in Hepatic Epithelioid Hemangioendothelioma: Retrospective Evaluation in 20 Cases

OBJECTIVES: This study aimed to analyze the patterns of conventional ultrasound (CUS) and contrast-enhanced ultrasound (CEUS) in 20 patients with diagnosis of hepatic epithelioid hemangioendothelioma (HEHE). METHODS: Twenty patients (12 females and 8 males) with mean age of 43.6 ± 13.6 years were included in this study from January 2012 to May 2020. CUS, CEUS, computed tomography (CT) and magnetic resonance imaging (MRI) features of the twenty patients with histologically proven HEHE were retrospectively reviewed by two radiologists. The clinical manifestations and the pathological findings of all patients with HEHE are described. RESULTS: There were 3 types of HEHE in imaging, including single nodular (8/20, 40%), multifocal nodular (10/20, 50%), and diffuse type (2/20, 10%). The mean size of lesions was 4.2 ± 2.6 cm. B-mode ultrasound of HEHE showed hypoechoic (15/20, 75%), heterogeneous echogenicity (4/20, 20%), or hyperechoic (1/20, 5%) lesions with regular shape (18/20, 90%) near the liver capsule (17/20, 85%), and occasionally with a halo (4/20, 20%) and calcifications (3/20, 15%). Eight out of the 20 patients also had CEUS. On CEUS, HEHE demonstrated peripheral rim-like (5/8, 62.5%), heterogeneous (2/8, 25%), or homogeneous (1/8, 12.5%) hyperenhancement in the arterial phase. All patients (8/8, 100%) showed hypoenhancement in the portal and late phase. CEUS detected more lesions than CUS in 3 patients (3/8, 37.5%). In addition, central irregular unenhanced zones were observed in 6 patients (6/8, 75%). On contrast-enhanced CT or MRI, most cases presented with capsule retraction sign and lollipop sign. CONCLUSIONS: HEHE demonstrated specific findings on ultrasound, which includes multifocal hypoechoic lesions in a subcapsular distribution with typical enhancement characteristics of malignant hepatic tumors.