Interesting ImagesPET/CT in Evaluation of Low Backache Due to Sacral Nerve Root Involvement Inflammatory and Malignant InvolvementYadav, Divya MD*; Angamuthu, Meivel MD*; Subudhi, T. Kishan MBBS*; Das, Chandan J. MD†; Kumar, Rakesh MD*Author Information From the Departments of *Nuclear Medicine †Radiology, All India Institute of Medical Science, New Delhi, India. Received for publication November 14, 2019; revision accepted February 16, 2020. Conflicts of interest and sources of funding: none declared. Correspondence to: Rakesh Kumar, MD, Diagnostic Nuclear Medicine Division, Department of Nuclear Medicine, All India Institute of Medical Science, Rajkumari Amrit Kaur O.P.D. New Delhi 110029, India. E-mail: email@example.com. Online date: April 29, 2020 Clinical Nuclear Medicine: June 2020 - Volume 45 - Issue 6 - p e299-e300 doi: 10.1097/RLU.0000000000003021 Buy Metrics Abstract Low back pain with radiation to lower limbs is due to nerve root impingement or involvement in most cases. 18F-FDG PET/CT has shown sacral nerve root involvement in several peripheral nerve pathologies, including neurolymphomatosis, peripheral nerve sheath tumor, and plexopathies. We present 2 cases of a low back pain with ulcerative colitis and metastatic neuroendocrine tumor who underwent 18F-FDG PET/CT and 68Ga-DOTANOC PET/CT, respectively. PET/CT can be used as an adjunct tool to evaluate sacral nerve root involvement to look for malignant or inflammatory nerve involvement. Copyright © 2020 Wolters Kluwer Health, Inc. All rights reserved.