Spectrum of 18F-FDG Uptake in Bilateral Lung Parenchymal Diseases on PET/CT Bilateral lung parenchymal involvement is seen in infective as well as noninfective conditions, appearing as focal or diffuse lung disease. PET/CT with FDG helps in characterization (increased glucose utilization is seen by both inflammatory and neoplastic cells). In this article, we describe the spectrum of patterns of FDG uptake and associated CT changes involving bilateral lung parenchyma. Benign conditions described are aspiration pneumonia; pulmonary toxicity by bleomycin; infections, namely, sarcoidosis, miliary pulmonary tuberculosis, and pulmonary nocardiosis; and inflammatory conditions such as pulmonary Langerhans cell histiocytosis and pulmonary alveolar proteinosis. Neoplastic conditions described are bilateral pulmonary metastases and lymphangitic carcinomatosis. Received for publication March 11, 2019; revision accepted July 1, 2019. Conflicts of interest and sources of funding: none declared. Ethical approval: All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. Informed consent: The institutional review board of our institute approved this retrospective study, and the requirement to obtain informed consent was waived. Correspondence to: Rakesh Kumar, MD, PhD, Department of Nuclear Medicine, AIIMS Campus, E-81, Ansari Nagar (East), New Delhi 110029, India. E-mail: rkphulia@yahoo.com. Copyright © 2019 Wolters Kluwer Health, Inc. All rights reserved.

Pituitary Adenoma on 18F-Fluciclovine PET/CT A 69-year-old man presented with lower urinary tract symptoms and prostate biopsy showed prostate cancer. 18F-Fluciclovine PET/CT revealed abnormal increased radiotracer uptake within the prostate gland, and multiple osseous structures, suspicious for tumoral involvement. Incidentally, an expansile soft tissue density mass arising from sella turcica demonstrated increased radiotracer activity. MRI showed a lobulated enhancing mass centered in the sella and eroding into the sphenoid sinus. The differential diagnosis includes pituitary macroadenoma versus prostate cancer metastasis. The tumor was resected and the pathological diagnosis was pituitary adenoma. Received for publication May 3, 2019; revision accepted July 13, 2019. Conflicts of interest and sources of funding: none declared. Correspondence to: Jiaqiong Wang, MD, PhD, Division of Nuclear Medicine, Department of Radiology, Miller School of Medicine, University of Miami Hospital/Jackson Memorial Hospital. Nuclear Medicine, Central 248 JMH, 1611 NW 12th Avenue, Miami, FL 33136, USA. E-mail: jiaqiong.wang@jhsmiami.org. Copyright © 2019 Wolters Kluwer Health, Inc. All rights reserved.

Orbital Adult T-Cell Leukemia/lymphoma With Skin Involvement Demonstrated on FDG PET/CT An 85-year-old woman presented with decreased visual acuity. MRI of the brain revealed bilateral orbital masses, and FDG-PET/CT demonstrated moderate to intense uptake in the orbital tumors and thickened skin on the left lower leg. Biopsies of the orbital and cutaneous lesions revealed infiltration by T-cell lymphoma, and the presence of human T-cell lymphotropic virus type 1 antigens confirmed the diagnosis of adult T-cell leukemia/lymphoma (ATLL). Although orbital ATLL is rare, the skin is a common site of extranodal involvement of T-cell lymphomas, including ATLL, and FDG uptake by a cutaneous lesion can facilitate early diagnosis. Received for publication July 12, 2019; revision accepted July 12, 2019. Conflicts of interest and sources of funding: none declared. Correspondence to: Masatoshi Hotta, MD, Department of Nuclear Medicine, National Center for Global Health and Medicine, 1-21-1, Toyama, Shinjuku-ku, Tokyo, 162-8655, Japan. E-mail: masatoshihotta@yahoo.co.jp. Copyright © 2019 Wolters Kluwer Health, Inc. All rights reserved.

Decrease in 18F-Florbetapir Accumulation in the Cerebral Hemisphere With Hypoperfusion and Misery Perfusion Due to Chronic Atherosclerotic Occlusion of the Internal Carotid Artery A 67-year-old man had a slowly progressing impairment of recent memory. Cerebral angiography showed atherosclerotic occlusion of the right internal carotid artery with insufficient collateral circulation. Positron emission tomography (PET) using 15O2 gas showed reduced cerebral blood flow, reduced cerebral metabolic rate of oxygen, and elevated oxygen extraction fraction in the precentral region of the right cerebral hemisphere. Use of 18F-florbetapir PET depicted amyloid β deposition as decreased tracer uptake in the precentral region in the right cerebral hemisphere when compared with the contralateral hemisphere. Received for publication May 30, 2019; revision accepted July 12, 2019. Conflicts of interest and sources of funding: This study was partly funded by a Grant-in-Aid for Strategic Medical Science Research from the Ministry of Education, Culture, Sports, Science and Technology of Japan (S1491001); and Scientific Research from the Japan Society for the Promotion of Science (JP18K09002). None declared to all authors. Correspondence to: Kuniaki Ogasawara, MD, Department of Neurosurgery, Iwate Medical University, 19-1 Uchimaru, Morioka, 020-8505 Japan. E-mail: kuogasa@iwate-med.ac.jp. Copyright © 2019 Wolters Kluwer Health, Inc. All rights reserved.

Scrotal Fibroepithelial Polyp With Acute and Chronic Inflammation Mimics Malignancy on 18F-FDG PET/CT Imaging Computed tomography (CT) of a 68-year-old man showed multiple small nodules in the bilateral lungs (maximum 14 mm in the left upper lobe). CT-guided biopsy of left upper lobe lesion showed no tumor or granuloma. Fluorodeoxyglucose (FDG) PET/CT showed multiple nodules with background-to-mild FDG-avid activity, and an incidental left scrotal skin lesion with intensely increased accumulation of 18F-FDG (SUVmax, 11.7), suspected malignant. After urologist consultation, local dermatological findings suggested a huge wart. Excision was done, and pathology concluded nodular papillary fibroepithelial polyp with acute and chronic inflammation. Received for publication May 13, 2019; revision accepted July 11, 2019. Conflicts of interest and sources of funding: none declared. Correspondence to: Yuh-Feng Wang, MD, PhD, Department of Nuclear Medicine, Dalin Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, No. 2, Minsheng Rd, Dalin Township, Chiayi 622, Taiwan, Republic of China. E-mail: yuhfeng@gmail.com. This is an open-access article distributed under the terms of the Creative Commons Attribution-Non Commercial-No Derivatives License 4.0 (CCBY-NC-ND), where it is permissible to download and share the work provided it is properly cited. The work cannot be changed in any way or used commercially without permission from the journal. Copyright © 2019 Wolters Kluwer Health, Inc. All rights reserved.

Increased FDG Uptake in the Center of the Gallbladder Stone: An Enigma We present a case with a large gallbladder stone showing central hypermetabolism detected incidentally by an FDG PET/CT scan. However, the same gallbladder stone did not showed any FDG activity on the FDG PET/CT scan performed 2 years ago. The mechanism of variable FDG uptake in the same gallbladder stone is unclear, which needs further investigation. Received for publication June 17, 2019; revision accepted July 9, 2019. Conflicts of interest and sources of funding: none declared. Correspondence to: Xia Ji, MM, Department of Gastroenterology, The Second Affiliated Hospital, Jiaxing University, 1518 North Huancheng Rd, Jiaxing 314000, Zhejiang Province, China. E-mail: zjjxmail@126.com. Copyright © 2019 Wolters Kluwer Health, Inc. All rights reserved.

Early-Phase 18F-Florbetaben PET as an Alternative Modality for 18F-FDG PET Purpose Based on the possibility that early-phase florbetaben (E-FBB) brain PET can be a surrogate for brain perfusion imaging, we conducted this study to investigate the clinical utility of E-FBB PET instead of 18F-FDG brain PET. Materials and Methods This prospective study included 35 patients with clinical suspicion of cognitive decline or dementia and 5 healthy controls. Brain MRI, E-FBB PET, late-phase FBB PET, and FDG PET were acquired. The regional SUV ratios (SUVRs) were calculated by cortical surface region of interest analysis using individual MRI, and relationship between E-FBB and FDG PET was analyzed. All PET scans were scored and analyzed as per visual scoring system, which represent tracer uptake abnormality. Moreover, uptake patterns were analyzed to determine the disease. Results Among the 40 subjects, 19 were amyloid-positive and 21 were amyloid-negative on late-phase FBB PET. Cortical surface region of interest analysis conducted for comparing between E-FBB and FDG PET revealed significant correlations (P < 0.0001) for regional SUVR among all brain regions; however, the SUVR values of FDG PET were statistically higher than those of E-FBB PET. Similarly, although the visually rated scores for E-FBB and FDG PET showed significant correlation (P < 0.0001), it was considered that the tracer uptake was more severely decreased for FDG PET. The disease types, specified by E-FBB and FDG PET, were statistically correlated. Conclusions E-FBB PET could potentially be a useful biomarker for the diagnosis of dementia in place of FDG PET. Nevertheless, the severity of the disease was more accurately determined by FDG PET. Received for publication May 20, 2019; revision accepted July 7, 2019. Seung Hyun Son and Kyunghun Kang contributed equally to this work as first authors. Conflicts of interest and sources of funding: This research was supported by Basic Science Research Program through the National Research Foundation of Korea funded by the Ministry of Education (2016R1D1A3B03934068) and supported by a grant of the Korea Health Technology R&D Project through the Korea Health Industry Development Institute, funded by the Ministry of Health & Welfare, Republic of Korea (grant number: HI15C0001). This work was supported by the National Research Foundation of Korea grant funded by the Korea government (Ministry of Science and ICT) (No. 2017R1C1B5018354). The authors declare no conflicts of interest. Correspondence to: Uicheul Yoon, PhD, Department of Biomedical Engineering, Daegu Catholic University, Hayang-Ro 13-13, Hayang-Eup, Gyeongsan-si, Gyeongbuk, Republic of Korea, 38430. E-mail: yoonuc@cu.ac.kr; and Shin Young Jeong, MD, PhD, Department of Nuclear Medicine, Kyungpook National University Chilgok Hospital, 807 Hoguk-ro, Buk-gu, Daegu, Republic of Korea, 41404. E-mail: syjeong@knu.ac.kr. Copyright © 2019 Wolters Kluwer Health, Inc. All rights reserved.

Atypical Parkinson Syndrome Hiding a Meningioma A 59-year-old man had developed within a few months walking disorders and rigidity of the left upper limb. 123I-FP-CIT SPECT/CT was performed in response to the suspicion of atypical parkinsonian syndrome. It showed an anomaly in presynaptic dopaminergic transmission on the right striatum and a voluminous expansive process on CT. MRI revealed an atypical meningioma. The patient had surgery for tumor removal. Later 123I-FP-CIT SPECT/CT showed normalization of presynaptic dopaminergic transmission on the right striatum. Received for publication July 2, 2019; revision accepted July 6, 2019. Conflicts of interest and sources of funding: none declared. Correspondence to: Caroline Bund, MD, MSc, Service de Biophysique et de Médecine Nucléaire, Hôpitaux Universitaires de Strasbourg, Hôpital de Hautepierre, 1, Avenue Molière, 67098 Strasbourg Cedex 09, France. E-mail: Caroline.BUND@chru-strasbourg.fr. Copyright © 2019 Wolters Kluwer Health, Inc. All rights reserved.

What Does Reduced FDG Uptake Mean in High-Grade Gliomas? Purpose As well as in many others cancers, FDG uptake is correlated with the degree of malignancy in gliomas, that is, commonly high FDG uptake in high-grade gliomas. However, in clinical practice, it is not uncommon to observe high-grade gliomas with low FDG uptake. Our aim was to explore the tumor metabolism in 2 populations of high-grade gliomas presenting high or low FDG uptake. Methods High-resolution magic-angle spinning nuclear magnetic resonance spectroscopy was realized on tissue samples from 7 high-grade glioma patients with high FDG uptake and 5 high-grade glioma patients with low FDG uptake. Tumor metabolomics was evaluated from 42 quantified metabolites and compared by network analysis. Results Whether originating from astrocytes or oligodendrocytes, the high-grade gliomas with low FDG avidity represent a subgroup of high-grade gliomas presenting common characteristics: low aspartate, glutamate, and creatine levels, which are probably related to the impaired electron transport chain in mitochondria; high serine/glycine metabolism and so one-carbon metabolism; low glycerophosphocholine-phosphocholine ratio in membrane metabolism, which is associated with tumor aggressiveness; and finally negative MGMT methylation status. Conclusions It seems imperative to identify this subgroup of high-grade gliomas with low FDG avidity, which is especially aggressive. Their identification could be important for early detection for a possible personalized treatment, such as antifolate treatment. Received for publication April 30, 2019; revision accepted July 4, 2019. Ethics approval and consent to participate: The Ethics Committee of Strasbourg approved the study (no. 2003-100, September 12, 2003 and no. 2013-37, December 11, 2013). Written informed consent was obtained from all patients included. Informed consent: Informed consent was obtained from all individual participants included in the study. A written informed consent was obtained from all the patients included. Conflicts of interest and sources of funding: none declared. Correspondence to: Caroline Bund, MD, MSc, Service de Biophysique et de Médecine Nucléaire, Hôpitaux Universitaires de Strasbourg, Hôpital de Hautepierre, 1, Avenue Molière, 67098 Strasbourg Cedex 09, France. E-mail: Caroline.BUND@chru-strasbourg.fr. Copyright © 2019 Wolters Kluwer Health, Inc. All rights reserved.

68Ga-PSMA-HBED-CC PET/CT and 18F-FDG PET/CT in Ewing Sarcoma We present a case of a 19-year-old woman with Ewing sarcoma of the iliac bone in whom 68Ga-PSMA-HBED-CC PET/CT showed high radiotracer activity in the primary tumor. The present case documents the in vivo expression of PSMA in Ewing sarcoma family of tumors and adds on to the list of nonprostatic malignancies showing PSMA expression. Received for publication April 26, 2019; revision accepted July 4, 2019. Conflicts of interest and sources of funding: none declared. Correspondence to: Bhagwant Rai Mittal, MD, DNB, Department of Nuclear Medicine, Postgraduate Institute of Medical Education and Research, Nehru Hospital, A-Block, Chandigarh 160012, India. E-mail: brmittal@yahoo.com. Copyright © 2019 Wolters Kluwer Health, Inc. All rights reserved.