Right retroperitoneal splenosis presenting as an adrenal mass

Ectopic splenic tissue may be congenital or acquired. Splenules can result from trauma or, less frequently, splenectomy, in which splenic parenchyma seeds accessible tissue to subsequently develop ectopic splenic tissue. This process of auto-transplantation is known as splenosis. Splenosis is a rare, benign condition most often found incidentally on imaging.1 Here, we describe a patient with a suspected adrenal malignancy successfully diagnosed as splenosis through Tc-99m labeled heat-damaged autologous red blood cell single-photon emission computed tomographycomputed tomography (SPECT-CT) imaging, thus avoiding surgical intervention.