FDG PET for giant cavernous hemangioma: important clue to differentiate from a malignant vascular tumor in the liver.

Giant cavernous hemangioma of the liver sometimes has a very inhomogeneous appearance with intratumoral degeneration on computed tomography or magnetic resonance imaging, and may mimic a malignant hepatic tumor, including angiosarcoma. There are many reports about F-18 fluorodeoxyglucose (FDG) uptake of angiosarcoma; however, knowledge regarding positron emission tomography findings with FDG for giant hepatic cavernous hemangioma is still limited. We herein present 2 cases of giant hepatic cavernous hemangioma in which low FDG uptake was considered helpful to differentiate from malignant hepatic tumor.