Interesting Images18F-Fluorodeoxyglucose PET/CT-Guided Palliative Radiotherapy Provides Durable Responses to Over a Dozen Sites of Disease in Relapsed Myeloid SarcomaShuttleworth, Charles MBBS, FRACP, FRCPA∗,†; Wegner, Eva A. MS, MHM, BMed, FRACP, FAAN†,‡; Thompson, Stephen R. PhD, MBBS, FRANZCR†,§; Kidson-Gerber, Giselle MBBS, FRACP, FRCPA∗,†Author Information From the ∗Department of Haematology, Prince of Wales Hospital †Faculty of Medicine, University of New South Wales Departments of ‡Nuclear Medicine and PET §Radiation Oncology, Prince of Wales Hospital, Sydney, Australia. Received for publication March 26, 2020; revision accepted June 28, 2020. Conflicts of interest and sources of funding: none declared. Correspondence to: Charles Shuttleworth, MBBS, FRACP, FRCPA, Department of Haematology, St George Public Hospital, Gray St, Kogarah NSW 2217, Australia. E-mail: [email protected]. Clinical Nuclear Medicine: November 2020 - Volume 45 - Issue 11 - p 886-887 doi: 10.1097/RLU.0000000000003238 Buy Metrics Abstract Myeloid sarcoma (MS) is a rare entity, and FDG PET/CT is a useful tool for staging at diagnosis and response assessment. We present a case of a 72-year-old woman diagnosed with multifocal extramedullary MS, using FDG PET/CT to guide palliative radiotherapy to 13 sites of disease over 2 separate relapses with complete and durable local responses and minimal toxicity. This case represents the largest reported burden of disease in MS successfully treated with FDG PET/CT-guided radiotherapy. Copyright © 2020 Wolters Kluwer Health, Inc. All rights reserved.