Clinical characteristics and CT features of hepatic epithelioid haemangioendothelioma and comparison with those of liver metastases

Abstract

Background To analyse clinical characteristics and computer tomography (CT) findings of hepatic epithelioid haemangioendothelioma (HEH) and to determine differential features compared with liver metastasis (LM). Methods This retrospective study included 80 patients with histopathologically confirmed HEH (n = 20) and LM (n = 60) of different primary tumours who underwent dynamic contrast-enhanced CT scans. CT findings included the location, contour, size, number, margin, and density of lesions, the patterns and degree of contrast enhancement of lesions, vascular invasion and changes in other organs. The enhancement ratio (ER) and tumour-to-normal parenchyma ratio (TNR) were calculated. Receiver operating characteristic curves (ROCs) were used to determine areas under the curve (AUCs). Results About 65% of HEH lesions were located in submarginal areas. Significant differences were observed between HEH and LM patients in age, sex, and tumour marker positivity (p < 0.05). HEH showed minimal to slight enhancement, thin ring-like enhancement in arterial phase, and slight, homogeneous, progressive enhancement in the portal phase. HEH presented capsule retraction, and the “target” sign and the “lollipop” sign were significantly more frequent than in LM (p < 0.05). The ER and TNR in the arterial phase of HEH were lower than those of LM (p < 0.05). AUCs of ER and TNR in the arterial phase were 0.74 and 0.73, respectively. Conclusion Lesions in subcapsular locations, capsular retraction, slight and thin ring-like enhancement, “target” and “lollipop” signs and lower ER and TNR in the arterial phase may represent important features of HEH compared with LM.

Case report: Successful treatment with the combined therapy of interferon-alpha 2b and anlotinib in a patient with advanced hepatic epithelioid hemangioendothelioma

“…Due to the differences in the biological behavior of the tumor, patients with HEH had a huge discrepancy in longterm survival (16). The radiological characteristics of HEH have been reported, such as a coalescent lesion, subcapsular lesion, capsular retraction, lollipop sign, and target sign (5,17,18). We have investigated the MRI appearances of 57 patients with HEH and the results showed that capsular retraction and lollipop sign were specific features of HEH, which could be used for differential diagnosis (5).…”

ACG Clinical Guideline: Focal Liver Lesions

“…On cross-sectional imaging (CT or MRI), HEHE is often present in a subcapsular location with capsular retraction and calcifications. Enhancement can vary and present as mild homogeneous enhancement seen on all phases or thin ring-like enhancement in the arterial phase, with progressive enhancement in the portal venous phase (171) (Figure 9). The characteristic imaging sign is the “lollipop” sign, which is due to tumor spread along the portal and hepatic vein branches and sinusoids, resulting in vascular and sinusoidal narrowing and obstruction (172).…”

“…The narrowing and occluded vessels are like sticks on the lesion, simulating the lollipop appearance (173). Another radiographic sign of HEHE on imaging is the “target” sign, which is an inner ring that consists of a fibrotic center, a middle ring of epithelial proliferation, and an outer ring defined by an avascular zone between the nodule and the liver parenchyma (171). The presence of capsular retraction, lollipop sign, and the target sign together is fairly specific for HEHE, and the presence of these features warrants further investigation (174).…”

CT appearances and classification of hepatic epithelioid hemangioendothelioma

“…Thus, analyzing and summarizing the radiological features of HEH are very important. Several studies have reported that subcapsular lesions, coalescent lesions, capsular retraction, target sign and lollipop sign are the radiological features of HEH [ 10 – 13 ]. However, considering the limited cases, the results of these studies failed to provide a comprehensive description of HEH on MRI or CT scans, based on a large group of patients.…”