Thoracic Splenosis Mimicking Metastatic Neuroendocrine Tumor (NET)

A 64-year-old man presented with abdominal pain. CT scan showed a 5mm left ureter stone, mesenteric root mass as well as a left lung pleuralbased lesion. Metastatic Neuroendocrine Tumor (NET) was suspected, hence a Gallium-68 Dotatate PET was performed. It showed intense uptake in the mesenteric mass, as well as in the pleural nodule, and no intense uptake in the liver. The liver is the most common site for small bowel NET metastasis. It is unusual to have pleural metastasis without liver metastasis. A review of this patient’s past medical history revealed a motor vehicle accident 20 years ago which required an exploratory laparotomy and splenectomy. Gallium 68 Dotatate PET scan can detect splenosis because it has somatostatin receptors. In patients with an existing neoplasm, metastases should be ruled out before confirming the diagnosis of splenosis. CT-guided biopsy of pleura nodule was performed, which confirmed the diagnosis of splenosis.