Differentiating intrahepatic splenosis from hepatocellular carcinoma

A female patient in her 70s with a past history of splenectomy was referred to our institution due to chronic hepatitis C accompanying a stage 2 liver tumor. The tumor was a low-echoic nodule, 2 cm in size, enhanced in the arterial phase, and isodense in the portal venous phase of contrast-enhanced computed tomography. Contrast-enhanced magnetic resonance imaging showed a low signal in the hepatobiliary phase. Since these imaging findings were atypical for hepatocellular carcinoma (HCC), we performed a liver biopsy, which showed intrahepatic splenosis. Superparamagnetic iron oxides-magnetic resonance imaging was also performed and the findings were consistent with splenosis. Splenosis is heterotopic implantation of splenic fragments following splenic injury or splenectomy. It is difficult to distinguish from HCC in patients who are at high-risk for HCC such as those with hepatitis virus infection or liver cirrhosis. The possibility of splenosis should be considered in the differential diagnosis of a liver mass in patients with a history of splenic trauma or surgery.