Spenules Masquerader of Metastatic Disease

Abstract

Splenosis is heterotopic auto transplantation of splenic tissue usually following splenectomy and traumatic rupture of spleen. They result from seeding of the Splenosis is heterotopic autotransplantation of splenic tissue usually following splenectomy and traumatic rupture of spleen. They result from seeding of the peritoneal cavity with splenic tissue which recruits local blood supply. Splenules typically are rounded well-marginated soft tissue structures that measure less than 2 centimeters. A 52 year old female with past medical history of splenectomy in 1980 due to MVA, presented to our clinic with history of abdominal bloating last 5 months, decrease appetite and weight loss about 12lb for 6 months, constipation. She had guaiac positive stool, was admitted to the hospital and had colonoscopy that was suggestive of inflammation of sigmoid colon. CT scan abdomen was suggestive of diverticulosis with minimal inflammation. She was treated with antibiotics but her symptoms did not improve completely. A repeat CT was done which showed pelvic lymphadenopathy, peritoneal nodules and severe sigmoid inflammatory changes more suggestive of extrinsic compression and peritoneal disease. Patient had positive family history of breast and ovarian cancers. CEA, CA 19-9 and CA 125 were unremarkable. Based on her clinical presentation and family history ovarian cancer was suspected and gynecologist was consulted and thought that inflammation of sigmoid secondary to peritoneal disease. Surgery was consulted for possible pelvic malignancy with possible peritoneal metastasis. Patient underwent surgery, peritoneal nodule with frozen section showed splenules (remnant of spleen) with calcification, biopsy of sigmoid showed inflammatory bowel disease. Splenules are incidental findings of little clinical significance in most patients. However, they must be properly identified in various situations, such as: differentiating them from metastatic lesions, torsion, infarction, endometriosis, mesenchymal tumors and peritoneal mesothelioma. These differential diagnoses can be differentiated using clinical history and radiological appearance. On noncontract CT, the attenuation of splenules is comparable to that of the spleen. However, small splenules may be hypodense and if calcified as in our patient can be mistaken for metastatic disease. Fused SPECT/CT imaging with Tc-99m labeled denatured red blood cells facilitates the definitive diagnosis of a splenule and may also helpful in identifying splenules that have relocated within the abdominal cavity.Figure 1Figure 2