Primary Hepatic Angiosarcoma: Distinct Imaging Phenotypes Mirroring Histopathologic Growth Patterns in a Retrospective Human Study

Figures

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  Figure 1. Flow diagram of the patient inclusion procedure.

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  Figure 2. Fifty-seven-year-old woman with chronic hepatitis B diagnosed with primary hepatic angiosarcoma, presenting as non-mass-forming lesions with a sinusoidal growth pattern. Axial T2-weighted MRI (a) shows ill-defined, hyperintense lesions involving both hepatic lobes with hepatomegaly. Pre-contrast T1-weighted imaging (b) reveals hypointensity. In the arterial phase (c), peripheral hyperenhancement is seen. In the hepatobiliary phase (d), the margins are poorly defined with iso- to hypointensity. Diffusion-weighted imaging and the ADC map ((e,f); b = 800 s/mm2) show areas of diffusion restriction (arrows). Arterial-phase (g) and portal venous phase (h) CT images depict ill-defined lesions with heterogeneous parenchymal enhancement and hepatomegaly. Histopathology (i) with hematoxylin-eosin staining demonstrates cytologic atypia of endothelial cells lining dilated sinusoidal spaces among residual hepatic trabeculae.

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  Figure 3. Sixty-one-year-old woman with no significant medical history diagnosed with primary hepatic angiosarcoma exhibiting a non-mass-forming peliotic growth pattern. Unenhanced computed tomography (CT; (a)) shows multiple low-attenuation lesions. Dynamic contrast-enhanced CT in the arterial (b), portal venous (c), and delayed phases (d) shows progressive centripetal and peripheral enhancement. Systemic bone metastases were present but are not shown. Histopathology (e) with hematoxylin-eosin staining demonstrates oval-shaped tumor cells infiltrating in an alveolar-like arrangement within blood-filled spaces.

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  Figure 4. Eighty-five-year-old woman with hypertension and diabetes diagnosed with mass-forming, vasoformative primary hepatic angiosarcoma. Unenhanced CT (a) demonstrates multiple low-density masses involving both lobes with hepatomegaly. Arterial (b) and portal venous (c) phases show nodular or irregular flame-shaped enhancement. The delayed phase (d) reveals progressive yet incomplete enhancement. These findings are consistent with the classic imaging features of hepatic angiosarcoma described in the literature. Histopathology (e) with hematoxylin-eosin staining reveals a vasoformative pattern with irregular proliferation of abnormal vascular structures admixed with pleomorphic tumor cells.

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  Figure 5. Seventy-two-year-old woman without prior medical history diagnosed with mass-forming primary hepatic angiosarcoma displaying a spindle cell morphology predominating over the epithelioid component and demonstrating a non-vasoformative pattern. T2-weighted magnetic resonance imaging (MRI; (a)) shows a well-defined lesion with bright high signal in the left lobe and small T2 intermediate-to-high signal nodule in the right lobe, suggestive of intrahepatic metastasis. On arterial-phase T1-weighted MRI (b), the lesion appears irregular with central hyperenhancement. The portal venous phase (c) shows peripheral enhancement progression. Non-contrast computed tomography (CT; (d)) shows internal calcifications. Arterial (e) and portal (f) phases of contrast-enhanced CT show central enhancement similar to the aorta with peripheral progression of contrast filling. Histopathology (g) with hematoxylin-eosin staining shows atypical endothelial cells lining dilated sinusoidal spaces between hepatic trabeculae.