Intrahepatic Splenosis with Severe Iron Deposition Presenting with Atypical Magnetic Resonance Images

An intrahepatic mass was incidentally found in a 41-year-old man with a history of a traffic accident injury which resulted in removal of a ruptured spleen. Hepatic splenosis was considered in the differential diagnosis but magnetic resonance imaging showed hypointensity on T2-weighted images, atypical for normal spleen. Histologically, the mass showed sinusoidal structures and lymphoid follicular aggregates. Immunohistochemical study showed that the phenotype of the vascular lining cells was CD8-positive, CD31-positive, and CD34 negative, the pattern diagnostic for ectopic spleen. In addition, severe iron deposition was histologically demonstrated, which was considered as the cause of the hypointense T2-weighted images.