Abstract
We report a case of a benign mesosigmoid schwannoma showing high radiotracer concentration on FDG-PET. A 66-year-old woman was admitted for abdominal pain. Computed tomography showed a 5-cm mass in the abdomen ; the FDG-PET examination showed a high radiotracer concentration. Malilgnant lymphoma or abdominal mesenchymal tumor was thought to be the most likely diagnosis. The tumor was resected. The inferior mesenteric artery was involved. On histopathology, the tumor was found to be composed of spindle-shaped cell bundles ; it was S-100 protein-positive, CD34-negative, CD117-negative, and α-SMA-negative. There were no findings suggestive of malignancy. A final diagnose of a benign mesosigmoid Schwannoma was made.
