Contrast-enhanced imaging in hepatic epithelioid hemangioendothelioma: retrospective study of 10 patients.

Purpose:  The purpose of this study was to analyze imaging findings in hepatic epithelioid hemangioendothelioma (HEHE) with a particular focus on contrast-enhanced ultrasound (CEUS).

Materials And Methods:  This retrospective multicenter study included 10 patients with histologically proven HEHE from 5 European centers. All existing ultrasound images/videos were independently analyzed by 2 experienced examiners (DEGUM level III, internal medicine) using a standardized evaluation form. Patterns of contrast enhancement were correlated with computed tomography (CT), magnetic resonance imaging (MRI), and pathological findings.

Results:  B-mode ultrasound, CEUS, CT, and MRI were performed in 90 %, 70 %, 100 %, and 90 % of patients, respectively. Multifocal HEHE could be observed in 80 % with affection of both liver lobes in 70 %. Analysis of CEUS revealed 3 characteristic patterns that correlated well with contrast patterns on CT and MRI: (a) peripheral nodular enhancement with centripetal fill-in and wash-out in the portal venous and late venous phase (PVLP), (b) rim-like arterial enhancement with wash-out in the PVLP, and (c) inversed target sign with/without wash-out in the PVLP. Wash-out in the PVLP as a sign suspicious of malignancy was observed in 6/7 patients (85.7 %).

Conclusions:  Knowledge of the different characteristic CEUS patterns is of importance to avoid misdiagnosis due to resemblance of patterns A and B to the much more common focal liver lesions hemangioma and intrahepatic cholangiocarcinoma. Of importance, sonographers should be aware that wash-out in the PVLP might be absent in some patients.