Perianal Abscess Due to Ingested Foreign Body as an Incidental Finding On 18F-FDG-PET/CT

A 46-year-old man underwent FDG-PET/CT for re-staging of malignant melanoma. No metabolically active tumor sites were demonstrated, but intense FDG uptake was seen within the left perianal region associated with a soft tissue opacity on low-dose CT, consistent with an abscess containing a 23 mm linear foreign body. The lesion was subsequently explored surgically. The abscess was drained, and a wooden object measuring ~28 ×2 mm was retrieved. The object was consistent with a portion of the stick from a corn dog which the patient recalled eating some time before the restaging PET.