title: Glucagon-Like Peptide-1 Receptor PET/CT with 68Ga-NOTA-Exendin-4 for Detecting Localized Insulinoma: A Prospective Cohort Study.
abstract: Preoperative localization of insulinoma is a clinical dilemma. We aimed to investigate whether glucagon-like peptide-1 receptor (GLP-1R) PET/CT with (68)Ga-NOTA-MAL-cys(40)-exendin-4 ((68)Ga-NOTA-exendin-4) is efficient in detecting insulinoma.
  
  
  METHODS
  In our prospective cohort study, patients with endogenous hyperinsulinemic hypoglycemia were enrolled. CT, MRI, endoscopic ultrasound, and (99m)Tc-hydrazinonicotinamide-TOC SPECT/CT were done according to standard protocols. GLP-1R PET/CT was performed 30-60 min after the injection of (68)Ga-NOTA-exendin-4. The gold standard for diagnosis was the histopathologic results after surgery.
  
  
  RESULTS
  Of 52 recruited patients, 43 patients with histopathologically proven insulinomas were included for the imaging studies. Nine patients did not undergo surgical intervention. (68)Ga-NOTA-exendin-4 PET/CT correctly detected insulinomas in 42 of 43 patients with high tumor uptake (mean SUVavg ± SD, 10.2 ± 4.9; mean SUVmax ± SD, 23.6 ± 11.7), resulting in sensitivity of 97.7%. In contrast, (99m)Tc-hydrazinonicotinamide-TOC SPECT/CT showed a low sensitivity of 19.5% (8/41) in this group of patients; however, it successfully localized the tumor that was false-negative with GLP-1R PET/CT. The sensitivities of CT, MR, and endoscopic ultrasonography were 74.4% (32/43), 56.0% (14/25), and 84.0% (21/25), respectively.
  
  
  CONCLUSIONS
  (68)Ga-NOTA-exendin-4 PET/CT is a highly sensitive imaging technique for the localization of insulinoma.
authors.affiliation: Department of Nuclear Medicine, Chinese Academy of Medical Sciences and Peking Union Medical College Hospital, Beijing, China.
authors.forename: Yaping
authors.initials: Y
authors.lastname: Luo
authors.affiliation: Department of Nuclear Medicine, Chinese Academy of Medical Sciences and Peking Union Medical College Hospital, Beijing, China.
authors.forename: Qingqing
authors.initials: Q
authors.lastname: Pan
authors.affiliation: Department of Nuclear Medicine, Chinese Academy of Medical Sciences and Peking Union Medical College Hospital, Beijing, China.
authors.forename: Shaobo
authors.initials: S
authors.lastname: Yao
authors.affiliation: Department of Endocrinology, Chinese Academy of Medical Sciences and Peking Union Medical College Hospital, Beijing, China.
authors.forename: Miao
authors.initials: M
authors.lastname: Yu
authors.affiliation: Department of General Surgery, Chinese Academy of Medical Sciences and Peking Union Medical College Hospital, Beijing, China.
authors.forename: Wenming
authors.initials: W
authors.lastname: Wu
authors.affiliation: Department of Radiology, Chinese Academy of Medical Sciences and Peking Union Medical College Hospital, Beijing, China; and.
authors.forename: Huadan
authors.initials: H
authors.lastname: Xue
authors.affiliation: Laboratory of Molecular Imaging and Nanomedicine, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, Maryland.
authors.forename: Dale O
authors.initials: DO
authors.lastname: Kiesewetter
authors.affiliation: Department of Nuclear Medicine, Chinese Academy of Medical Sciences and Peking Union Medical College Hospital, Beijing, China.
authors.forename: Zhaohui
authors.initials: Z
authors.lastname: Zhu
authors.affiliation: Department of Nuclear Medicine, Chinese Academy of Medical Sciences and Peking Union Medical College Hospital, Beijing, China.
authors.forename: Fang
authors.initials: F
authors.lastname: Li
authors.affiliation: Department of General Surgery, Chinese Academy of Medical Sciences and Peking Union Medical College Hospital, Beijing, China zhaoyp_pumch@163.com shawn.chen@nih.gov.
authors.forename: Yupei
authors.initials: Y
authors.lastname: Zhao
authors.affiliation: Laboratory of Molecular Imaging and Nanomedicine, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, Maryland zhaoyp_pumch@163.com shawn.chen@nih.gov.
authors.forename: Xiaoyuan
authors.initials: X
authors.lastname: Chen
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D015331:Cohort Studies; D000077270:Exenatide; D005260:Female; D005710:Gallium Radioisotopes; D000067757:Glucagon-Like Peptide-1 Receptor / Q000378:metabolism*; D006571:Heterocyclic Compounds / Q000737:chemistry*; D006573:Heterocyclic Compounds, 1-Ring; D006801:Humans; D007340:Insulinoma / Q000000981:diagnostic imaging* / Q000378:metabolism / Q000473:pathology; D008297:Male; D008875:Middle Aged; D010190:Pancreatic Neoplasms / Q000000981:diagnostic imaging* / Q000378:metabolism / Q000473:pathology; D010455:Peptides / Q000737:chemistry*; D000072078:Positron Emission Tomography Computed Tomography; D011446:Prospective Studies; D014688:Venoms / Q000737:chemistry*; D055815:Young Adult
chemical_list: D005710:Gallium Radioisotopes; D000067757:Glucagon-Like Peptide-1 Receptor; D006571:Heterocyclic Compounds; D006573:Heterocyclic Compounds, 1-Ring; D010455:Peptides; D014688:Venoms; C048993:1,4,7-triazacyclononane-N,N',N''-triacetic acid; D000077270:Exenatide
keywords: PET/CT; exendin-4; glucagon-like peptide-1 receptor (GLP-1R); insulinoma