Intussusception caused by an ileocecal lymphoma disclosed on 18F-FDG-PET/CT.

A 55-year-old man presented with upper abdominal discomfort. Abdominal computed tomography (CT) and a colonoscopic biopsy revealed non-Hodgkin lymphoma of the ileocecal region. An FDG-PET/CT scan performed three days after colonoscopy demonstrated intense FDG activity in the right abdomen on a maximal projection PET image (Picture 1). There were no other foci of abnormal FDG activity. The CT portion of the PET/CT scan incidentally demonstrated the typical “target” sign of bowel intussusception (1) at the tail of the intussusceptum (Picture 2). The patient did not exhibit any symptoms of intussusception. A coronal fusion image simultaneously demonstrated a focal accumulation at the top of the intussusception (arrow) in the ascending colon and the intussusceptum with accompanying mesenteric fat (arrowheads) (Picture 3). The incidental finding of intussusception on PET/CT has been reported in children (2). Our case is the first case of malignant lymphoma as the lead point of intussusception in an adult.