Interesting Images“Hood Sign” in Nuclear Medicine: An Unusual Presentation of Mantle Cell Lymphoma as Detected on FDG PET/CTPrakash, Anjali MBBS, MD; Purandare, Nilendu MBBS, DMRD, DNB; Shah, Sneha MBBS, DRM, DNB; Agrawal, Archi MBBS, DMRE, DRM, DNB; Puranik, Ameya MBBS, DNB, MNMAS, FEBNM; Rangarajan, Venkatesh MBBS, DRM, DNB Author Information From the Department of Nuclear Medicine and Molecular Imaging, Tata Memorial Hospital, Homi Bhabha National Institute, Mumbai, India. Received for publication March 2, 2022; revision accepted June 25, 2022. Conflicts of interest and sources of funding: none declared. Informed consent: Informed consent was taken from the patient for the publication of this case report and related images. Correspondence to: Nilendu Purandare, MBBS, DMRD, DNB, Department of Nuclear Medicine and Molecular Imaging, Tata Memorial Hospital, Homi Bhabha National Institute, E Borges Rd, Parel, Mumbai 400012, India. E-mail: [email protected]. Clinical Nuclear Medicine: December 2022 - Volume 47 - Issue 12 - p e731-e732 doi: 10.1097/RLU.0000000000004359 Buy Metrics Abstract Mantle cell lymphoma is a rare and aggressive non-Hodgkin lymphoma with a high propensity for extranodal involvement, typically seen in the liver, marrow, and gastrointestinal system. Being an FDG-avid disease and a sensitive modality for detecting both nodal and extranodal disease, FDG PET/CT is recommended in the workup of mantle cell lymphoma. We present a rare pattern of cutaneous involvement of the head-neck region in a patient with mantle cell lymphoma, which can be described on FDG PET/CT as a “hood sign.” Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.