Differentiating primary hepatic angiosarcomas from hemangiomatosis and epithelioid hemangioendotheliomas using gadoxetic acid-enhanced and diffusion-weighted MR imaging

Objectives: To assess the value of gadoxetic acid-enhanced and diffusion-weighted (DW) magnetic resonance (MR) imaging for differentiating primary hepatic angiosarcomas from hemangiomatosis and epithelioid hemangioendotheliomas (EHEs). Methods: We reviewed MR images of seven patients with pathologically determined hepatic angiosarcomas, 11 patients with hemangiomatosis, and five patients with EHEs. Two radiologists assessed morphologic features, signal intensity (SI), enhancement patterns, and the presence of diffusion restriction by consensus and compared between angiosarcoma vs hemangiomatosis and angiosarcoma vs EHEs. Results: Angiosarcomas more frequently showed mixed well- and ill-defined margins (6, 85.7%), mixed strong and intermediate-high SI (5, 71.4%) on T2-weighted images, mixed peripheral and/or central nodular and rim and/or target enhancement (5, 71.4%), and mixed presence and absence of diffusion restriction (7, 100%) compared with hemangiomatosis and EHEs (P < 0.05). The overall survival rate in patients with angiosarcomas was 42.9% at 3 months and 14.3% at 14 months, whereas all patients with EHEs were alive during the follow-up period from 4 to 43 months (P = 0.002). Conclusion: Gadoxetic acid-enhanced and DW MR imaging may help differentiate primary hepatic angiosarcomas with hemangioma-like appearance, EHE-like appearance, or both; and poor prognosis from hemangiomatosis and EHEs.