IS Case 201: Multiple infantile hemangioendotheliomas of the liver
Imaging Sciences URMC 2008
Publication Date: 2009-05-22
MRI: Multiple T1-hypointense and T2-hyperintense round lesions are seen throughout the liver which enhance in a peripheral to central fashion with intravenous gadolinium administration. Another lesion with similar signal characteristics is seen in the subcutaneous fat of the right buttock.
Infantile hemangioendothelioma (IHE) is a benign tumor of the liver composed of vascular channels lined by a single or multiple layers of endothelial cells. Although the lesion is benign, children may die from associated conditions such as congestive heart failure. Other clinical associations including bleeding, anemia, and jaundice may be present. Cutaneous hemangiomas may be seen in anywhere from 9% to 87% of cases, as seen in this patient. These are not considered metastatic lesions from the liver, but are coexisting as a diffuse process of hemangiomatosis. The lesions typically are circumscribed and may be focal, multifocal, or diffuse. Large, solitary lesions tend to have central hemorrhage and/or necrosis.
Radiographs show hepatomegaly and occasionally finely speckled calcifications within the IFE. Congestive heart failure may be seen on chest radiographs. Scintigraphy reveals a different imaging appearance than adult hemangiomas. On Tc-99m-tagged red blood cell studies, IHE show increased flow during the angiographic phase (as opposed to adult hemangiomas which are generally photopenic). Delayed images show increased activity within the lesion unless there is central hemorrhage or necrosis. Sulfur colloid scans reveal photopenic defects. The ultrasound (US) appearance of IHE is variable, but tends to be either complex or hypoechoic, but may be hyperechoic as in our case. On Doppler US the hepatic artery and proximal aorta may be enlarged, with tapering of the aorta distal to the celiac artery. CT shows a low-attenuation mass that peripherally enhances with contrast and fills centrally. Large solitary lesions tend to retain a low-attenuation center, again due to hemorrhage or necrosis. On MRI, the lesions are generally of low-signal intensity on T1-weighted images and are hyperintense on T2-weighted images, similar to adult hemangiomas. The enhancement pattern is that seen on CT. Angiography may show enlarged hepatic and extrahepatic feeding vessels, pooling of contrast within the lesions, and arteriovenous shunting with early draining veins.
The differential diagnosis for IHE includes hepatoblastoma, mesenchymal hamartoma, and metastatic neuroblastoma. IHE follows a similar clinical course to cutaneous hemangiomas with a proliferative phase in the first 6 months followed by an involutional phase over several months to years. Treatment is not necessary in asymptomatic cases and these patients tend to do well with follow-up. For symptomatic cases, treatment varies and may include prednisone, digoxin, and furosemide. If medical management fails, embolization or surgical resection may be necessary. Very rarely, IHE has been suggested to undergo malignant transformation to angiosarcoma.
- Keslar PJ, Buck JL, Selby DM. From the archives of the AFIP. Infantile hemangioendothelioma of the liver revisited. Radiographics. 1993 May;13(3):657-70. [PMID: 8316672]