57 years old male patient attended to the hospital with complaint of weight loss. A mass lesion adjacent to the liver and stomach was demonstrated in the initial CT. Metabolic characterization of the lesion by F-18 FDG PET-CT showed mild FDG accumulation and undetermined mesenteric lesions as well as fragmentated appearance of the spleen. The anamnesis of the patient revealed abdominal trauma and additional SPECT-CT with Tc-99m Nanocolloid verified Splenosis.