Epithelioid hemangioendothelioma of the liver: radiologic-pathologic correlation

Contrast-enhanced ultrasound of histologically proven hepatic epithelioid hemangioendothelioma

AIM

To analyze contrast-enhanced ultrasound (CEUS) features of histologically proven hepatic epithelioid hemangioendothelioma (HEHE) in comparison to other multilocular benign focal liver lesions (FLL).

METHODS

Twenty-five patients with histologically proven HEHE and 45 patients with histologically proven multilocular benign FLL were retrospectively reviewed. Four radiologists assessed the CEUS enhancement pattern in consensus.

RESULTS

HEHE manifested as a single (n = 3) or multinodular (n = 22) FLL. On CEUS, HEHE showed rim-like (18/25, 72%) or heterogeneous hyperenhancement (7/25, 28%) in the arterial phase and hypoenhancement (25/25, 100%) in the portal venous and late phases (PVLP), a sign of malignancy. Eighteen patients showed central unenhanced areas (18/25, 72%); in seven patients (7/25, 28%), more lesions were detected in the PVLP. In contrast, all patients with hemangioma and focal nodular hyperplasia showed hyperenhancement as the most distinctive feature (P < 0.01).

CONCLUSION

CEUS allows for characterization of unequivocal FLL. By analyzing the hypoenhancement in the PVLP, CEUS can determine the malignant nature of HEHE.

Hepatic epithelioid hemangioendothelioma: MR imaging findings

We report the MRI findings in three patients with pathologically proven hepatic epithelioid hemangioendothelioma, a rare tumor of the liver that is not well described in the MR imaging literature. The recognition of the imaging features of this rare malignancy may help further early detection and surgical treatment of this potentially curable disease.

Hepatic epithelioid hemangioendothelioma: findings at CT and MRI including preliminary observations at diffusion-weighted echo-planar imaging

OBJECTIVE

Hepatic epithelioid hemangioendothelioma (EHE) is a rare vascular tumor with low- to intermediate-grade malignant potential. We describe cross-sectional imaging findings of pathologically confirmed EHE including preliminary observations on lesion characteristics and apparent diffusion coefficients (ADCs) at diffusion-weighted MR imaging (DWI).

METHODS

CT and MRI examinations in five patients were retrospectively reviewed. Two radiologists evaluated lesion growth patterns, attenuation, signal intensity characteristics, and contrast enhancement patterns. Additionally, DWI features on low and high b-value images as well as ADCs were assessed in three patients.

RESULTS

Imaging features of EHE included multifocal hepatic disease (n = 5), predominantly subcapsular location (n = 5), coalescence of nodules (n = 5), capsular retraction (n = 3), and intralesional calcifications (n = 3). Contrast-enhanced CT and MR images showed variable degrees of peripheral rim enhancement. T2-weighted MR images, low b-value DWI and ADC maps frequently depicted a "target-sign" appearance of tumor nodules. A markedly hyperintense central area corresponding to hypocellular stroma was surrounded by a moderately hyperintense outer rim reflecting hypercellular tumor regions. The mean ADC of lesions was 1.86 × 10(-3) mm(2)/s.

CONCLUSION

Cross-sectional imaging displayed typical features of EHE. The mean ADC value of lesions was found to be relatively high in comparison with other hepatic malignancies, which may be helpful in suggesting the diagnosis.

Hepatic epithelioid hemangioendothelioma in Taiwan: a clinicopathologic study of six cases in a single institution over a 15-year period

BACKGROUND/PURPOSE

Hepatic epithelioid hemangioendothelioma (HEH) is a rare vascular tumor of the liver typically with a slow but progressive course. We report the clinical and immunohistochemical characteristics of six cases from our institution between 1993 and 2008.

METHODS

We searched the files of the Department of Pathology in National Taiwan University Hospital from January 1993 to December 2008 and found six cases of primary HEH. The clinical data were reviewed. The microscopic findings of each case were listed and analyzed. Confirmational immunoperoxidase stains were performed with antibodies against two endothelial markers (CD31 and CD34) and one epithelial marker (AE1/AE3 or cytokeratin).

RESULTS

There were five female patients and one male patient with HEH, and the mean age was 45.3 years (range, 25-86 years). Most patients were asymptomatic and one third of cases presented as right costal or abdominal pain. Anemia was the most common laboratory abnormality. Liver failure developed at the advanced diffuse stage. Imaging studies revealed three different patterns as single nodular, multiple nodular, or diffuse types, reflecting different stages of disease and clinical symptoms. Microscopic findings included intracytoplasmic vascular lumen formation (100%), sinusoidal spreading (100%), vessel obliteration (66.7%), necrosis (66.7%), and cellular pleomorphism (16.7%). All cases expressed endothelial markers of CD31 and CD34, reflecting their vascular nature. Two patients received surgical treatment including partial liver resection and liver transplantation. Tumor recurrence developed 8 and 17 months later, respectively.

CONCLUSION

HEH showed insidious growth and frequent multicentricity, making early diagnosis and tumor resection difficult. Definite diagnosis totally relies on pathologic study. Tumor progression to hepatic failure is slow. Liver transplantation is currently the most prevalent treatment modality for HEH, but experience in Taiwan is limited due to the rarity of this disease.

[A case of primary hepatic epithelioid hemangioendothelioma with spontaneous rupture]

Primary hepatic epithelioid hemangioendothelioma is a rare neoplasm of endothelial origin. The clinical manifestations are nonspecific, ranging from complete absence of symptoms to hepatic failure and death. Spontaneous rupture of a hepatic epithelioid hemangioendothelioma is an extremely rare presentation. We present a case of primary hepatic epithelioid hemangioendothelioma in a 65-year-old male patient with alcoholic liver cirrhosis. He was hospitalized due to epigastric pain and multiple liver masses on abdominal ultrasound. Dynamic liver CT imaging revealed multiple peripheral nodular enhanced mass lesions with delayed centripetal enhancement, and the adjacent collection of high-attenuation fluid along the liver capsule. Abdominal tapping revealed blood in the peritoneal cavity. Primary hepatic epithelioid hemangioendothelioma with spontaneous rupture was finally diagnosed based on a histopathologic examination revealing positive immunohistochemical staining for CD34.

Magnetic resonance imaging of liver lesions: exceptions and atypical lesions

On state-of-the-art magnetic resonance imaging, most lesions can be detected and characterized with confidence according to well-known criteria. However, atypical characteristics in some common lesions and the incidental encounter with rare lesions may pose diagnostic difficulties. In this article, six challenging hepatic lesions will be discussed and evaluated on the most important magnetic resonance imaging sequences, with histological correlation when available. In addition, the background information concerning these lesions will be described based on the most recent available literature. By reading this article, the reader will be able to (1) categorize the lesion in solid and fluid-containing lesions, based on the T2 signal intensity; and (2) define the benign or malignant nature of the lesion, in relation to the signal intensity and dynamic enhancement pattern, despite the presence of atypical characteristics of some lesions.

Primary malignant hepatic epithelioid hemangioendothelioma: a comprehensive review of the literature with emphasis on the surgical therapy

Malignant hepatic epithelioid hemangioendothelioma (HEH) is a rare malignant tumor of vascular origin with unknown etiology and a variable natural course. The authors present a comprehensive review of the literature on HEH with a focus on clinical outcome after different therapeutic strategies. All published series on patients with HEH (n = 434 patients) were analyzed from the first description in 1984 to the current literature. The reviewed parameters included demographic data, clinical manifestations, therapeutic modalities, and clinical outcome. The mean age of patients with HEH was 41.7 years, and the male-to-female ratio was 2:3. The most common clinical manifestations were right upper quadrant pain, hepatomegaly, and weight loss. Most patients presented with multifocal tumor that involved both lobes of the liver. Lung, peritoneum, lymph nodes, and bone were the most common sites of extrahepatic involvement at the time of diagnosis. The most common management has been liver transplantation (LTx) (44.8% of patients), followed by no treatment (24.8% of patients), chemotherapy or radiotherapy (21% of patients), and liver resection (LRx) (9.4% of patients). The 1-year and 5-year patient survival rates were 96% and 54.5%, respectively, after LTx; 39.3% and 4.5%, respectively, after no treatment, 73.3% and 30%, respectively, after chemotherapy or radiotherapy; and 100% and 75%, respectively, after LRx. LRx has been the treatment of choice in patients with resectable HEH. However, LTx has been proposed as the treatment of choice because of the hepatic multicentricity of HEH. In addition, LTx is an acceptable option for patients who have HEH with extrahepatic manifestation. Highly selected patients may be able to undergo living-donor LTx, preserving the donor pool. The role of different adjuvant therapies for patients with HEH remains to be determined.

Apresentações incomuns do hemangioma hepático: ensaio iconográfico

O nosso objetivo foi descrever e ilustrar aspectos incomuns do hemangioma hepático na ultra-sonografia (US), tomografia computadorizada (TC) e ressonância magnética (RM). A partir da análise retrospectiva de 300 casos de pacientes com diagnósticos de hemangioma hepático, por meio da análise combinada de exames de imagem, biópsia ou acompanhamento clínico, selecionamos aqueles com apresentação atípica em um ou mais métodos de imagem ou aqueles com evolução não usual, ilustrando os seus principais aspectos de imagem. Entre os casos apresentados, escolhemos pacientes com hemangiomas: hipoecogênicos na US; hipovasculares ou avasculares na TC e RM; com calcificações grosseiras; gigantes e medindo mais de 20 cm de diâmetro; predominantemente exofíticos; hipointensos em T2; promovendo defeito de perfusão; com cicatriz central e simulando hiperplasia nodular focal; com crescimento evolutivo. O hemangioma hepático é o tumor mais comum do fígado e geralmente tem apresentação típica. Porém, os seus diversos aspectos não usuais precisam ser conhecidos para auxiliar na orientação diagnóstica e conduta.

The lollipop sign: a new cross-sectional sign of hepatic epithelioid hemangioendothelioma

In four cases of hepatic epithelioid hemangioendothelioma (HEHE), multiple liver lesions were depicted on enhanced computed tomography (CT) and/or magnetic resonance imaging (MRI) scans. A peculiar sign, a hepatic or portal vein terminating at or just within the periphery of some of the liver lesions, was noted in all four; the images look like a lollipop. Imaging findings of HEHE can suggest other diseases, but this sign buttressed by other radiological findings, seems to be specific for this entity.