Interesting Images18F-FDG PET/CT for Monitoring of Disease Progression in Metastatic Perivascular Epithelioid Cell TumorHolzgreve, Adrien MD∗; Fabritius, Matthias P. MD†; Knösel, Thomas MD‡; Renz, Bernhard W. MD§; Lindner, Lars H. MD∥; Di Gioia, Dorit MD∥; Bartenstein, Peter MD∗; Rübenthaler, Johannes MD†; Tiling, Reinhold MD∗Author Information From the Departments of ∗Nuclear Medicine †Radiology, University Hospital, LMU Munich ‡Institute of Pathology, Faculty of Medicine Departments of §General, Visceral, and Transplant Surgery ∥Internal Medicine III, University Hospital, LMU Munich, Munich, Germany. Received for publication August 10, 2020; revision accepted October 25, 2020. Conflicts of interest and sources of funding: none declared. Author’s Contributions: A.H.: clinical management, draft manuscript. T.K.: histopathological analyses, increased intellectual content. B.W.R., L.H.L., D.D.G.: clinical management, increased intellectual content. M.P.F., P.B., J.R.: revision manuscript, increased intellectual content. R.T.: draft manuscript, supervision. Correspondence to: Adrien Holzgreve, MD, Department of Nuclear Medicine, University Hospital, LMU Munich, Marchioninistr. 15, 81377 Munich, Germany. E-mail: [email protected]. Clinical Nuclear Medicine: February 2021 - Volume 46 - Issue 2 - p 156-158 doi: 10.1097/RLU.0000000000003453 Buy Metrics Abstract A 38-year-old woman presented for 18F-FDG PET/CT after multiple intra-abdominal surgical resections of a rare recurrent perivascular epithelioid cell tumor of the gastrointestinal tract. A solitary pelvic metastasis was detected, but surprisingly exhibited neither increased glucose consumption nor contrast enhancement on CT. Follow-up 18F-FDG PET/CT staging in the further disease course revealed multiple abdominal metastases, now, however, with markedly increased 18F-FDG uptake and intraoperatively correlating widespread peritoneal sarcomatosis. This case gives preliminary insight into monitoring of disease progression in metastatic perivascular epithelioid cell tumor, although the underlying pathophysiological bases for varying 18F-FDG uptake in PET/CT are not yet fully understood. Copyright © 2020 Wolters Kluwer Health, Inc. All rights reserved.