Magnetic resonance imaging of siderotic hepatic adenoma.

This is a case report of a patient with hepatic adenoma who had a magnetic resonance imaging (MRI) appearance mimicking that of adenomatous hyperplasia. The adenoma was hyperintense on T1-weighted image (T1WI) and hypointense on T2-weighted image (T2WI). Pathologically, iron deposition in hepatocytes and Kupffer cells was proved by Prussian blue stain that caused hypointensity on T2WI. Iron deposition in hepatic adenomatous hyperplasia has been documented in the past, but there are no reports of siderotic adenoma in the literature. We suggest that siderotic hepatic adenoma be included in the differential diagnosis when MRI appearance is hyperintense on T1WI and hypointense on T2WI.