Interesting ImagesAcute Aortic Dissection Initially Suspected on 18F-FDG PET/CTUlaner, Gary A. MD, PhD∗,†; Muehlbauer, Stefan MD, PhD‡; Goldberg, Zoe MD§Author Information From the ∗Department of Radiology, Memorial Sloan Kettering Cancer Center †Department of Radiology, Weill Cornell Medical College, New York ‡Department of Emergency Medicine, St Francis Hospital, Roslyn §Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, NY. Received for publication May 18, 2020; revision accepted June 2, 2020. Conflicts of interest and sources of funding: none declared. Correspondence to: Gary A. Ulaner, MD, PhD, Memorial Sloan Kettering Cancer Center, 1275 York Ave, Box 77, New York, NY 10065. E-mail: email@example.com. Clinical Nuclear Medicine: October 2020 - Volume 45 - Issue 10 - p 819-820 doi: 10.1097/RLU.0000000000003209 Buy Metrics Abstract A 64-year-old man with anal cancer underwent follow-up 18F-FDG PET/CT to evaluate chemoradiation therapy response 5 months after an initial PET/CT. The follow-up 18F-FDG PET/CT demonstrated new FDG-avid curvilinear soft tissue adjacent to the abdominal aorta, interpreted as an aortic dissection. Despite lack of clinical symptoms, the patient was directed to an emergency room the same day, where a contrast-enhanced CT confirmed an aortic aneurysm with dissection. The patient underwent endovascular surgical repair the following day. This case demonstrates that newly FDG-avid aortic soft tissue should be recognized and may need further evaluation to characterize clinically significant vascular pathology. Copyright © 2020 Wolters Kluwer Health, Inc. All rights reserved.