Interesting ImagesLarge Idiopathic Mesenteric Necrotizing Granuloma Mimicking Metastatic Disease on FDG PET/CTLiu, Yiyan MD, PhDAuthor Information From the Nuclear Medicine Service, Department of Radiology, New Jersey Medical School, Rutgers University, Newark, NJ. Received for publication October 21, 2019; revision accepted December 7, 2019. Conflicts of interest and sources of funding: none declared. Correspondence to: Yiyan Liu, MD, PhD, Nuclear Medicine Service, Department of Radiology, University Hospital, H-141, 150 Bergen St, Newark, NJ 07103. E-mail: firstname.lastname@example.org. Online date: January 30, 2020 Clinical Nuclear Medicine: April 2020 - Volume 45 - Issue 4 - p 314-315 doi: 10.1097/RLU.0000000000002958 Buy Metrics Abstract On restaging FDG PET/CT for an 81-year-old man with oral cavity cancer, a large FDG-avid mesenteric mass suspicious for either metastasis or second primary was incidentally noted. Surgical pathology showed necrotizing granulomatous inflammation without evidence of tumor. All stains were negative for microorganisms. An elastin stain was negative as well, which excluded an origin of damaged blood vessels or vasculitis. The patient had no prior abdominal surgery or known gastrointestinal disease. Granuloma always poses a dilemma in the interpretation of PET/CT, due to its high FDG avidity and mass-like appearance which mimics neoplastic disease. Copyright © 2020 Wolters Kluwer Health, Inc. All rights reserved.