Intra-Abdominal Splenosis Mimicking Metastatic Cancer

Splenosis, the heterotopic autotransplantion of splenic tissue, is a common benign condition among patients with a history of splenic trauma. Most cases of splenosis are intra-abdominal due to direct seeding of surrounding structures, although these ectopic rests may occur almost anywhere in the body, and its diffuse nature may raise the suspicion of metastatic cancer. Confirmation of splenic tissue can be made by technetium-99m (Tc-99m) sulfur colloid scintigraphy or with Tc-99m heat-damaged red blood cells; however, in some cases, biopsy may be required for definitive diagnosis. Here, the authors present a patient with a remote history of posttraumatic splenectomy who was discovered to have multiple intra-abdominal nodules by CT scan. A diagnosis of diffuse metastatic disease was initially considered before a diagnosis of intra-abdominal splenosis was ultimately made with the aid of Tc-99m sulfur colloid single-positron emission computed tomography (SPECT) and computed tomography imaging.