title: 64Cu-DOTATATE for Noninvasive Assessment of Atherosclerosis in Large Arteries and Its Correlation with Risk Factors: Head-to-Head Comparison with 68Ga-DOTATOC in 60 Patients.
abstract: The somatostatin receptor subtype 2 is expressed on macrophages, an abundant cell type in the atherosclerotic plaque. Visualization of somatostatin receptor subtype 2, for oncologic purposes, is frequently made using the DOTA-derived somatostatin analogs DOTATOC or DOTATATE for PET. We aimed to compare the uptake of the PET tracers (68)Ga-DOTATOC and (64)Cu-DOTATATE in large arteries, in the assessment of atherosclerosis by noninvasive imaging technique, combining PET and CT. Further, the correlation of uptake and cardiovascular risk factors was investigated.
  
  
  METHODS
  Sixty consecutive patients with neuroendocrine tumors underwent both (68)Ga-DOTATOC and (64)Cu-DOTATATE PET/CT scans, in random order. For each scan, the maximum and mean standardized uptake values (SUVs) were calculated in 5 arterial segments. In addition, the blood-pool-corrected target-to-background ratio was calculated. Uptake of the tracers was correlated with cardiovascular risk factors collected from medical records.
  
  
  RESULTS
  We found detectable uptake of both tracers in all arterial segments studied. Uptake of (64)Cu-DOTATATE was significantly higher than (68)Ga-DOTATOC in the vascular regions both when calculated as maximum and mean uptake. There was a significant association between Framingham risk score and the overall maximum uptake of (64)Cu-DOTATATE using SUV (r = 0.4; P = 0.004) as well as target-to-background ratio (r = 0.3; P = 0.04), whereas no association was found with (68)Ga-DOTATOC. The association of risk factors and maximum SUV of (64)Cu-DOTATATE was found driven by body mass index, smoking, diabetes, and coronary calcium score (P < 0.001, P = 0.01, P = 0.005, and P = 0.03, respectively).
  
  
  CONCLUSIONS
  In a series of oncologic patients, vascular uptake of (68)Ga-DOTATOC and (64)Cu-DOTATATE was found, with highest uptake of the latter. Uptake of (64)Cu-DOTATATE, but not of (68)Ga-DOTATOC, was correlated with cardiovascular risk factors, suggesting a potential role for (64)Cu-DOTATATE in the assessment of atherosclerosis.
authors.affiliation: Department of Clinical Physiology, Nuclear Medicine & PET, Rigshospitalet & Cluster for Molecular Imaging, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Catarina
authors.initials: C
authors.lastname: Malmberg
authors.affiliation: Department of Clinical Physiology, Nuclear Medicine & PET, Rigshospitalet & Cluster for Molecular Imaging, University of Copenhagen, Copenhagen, Denmark ripa@sund.ku.dk.
authors.forename: Rasmus S
authors.initials: RS
authors.lastname: Ripa
authors.affiliation: Department of Clinical Physiology, Nuclear Medicine & PET, Rigshospitalet & Cluster for Molecular Imaging, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Camilla B
authors.initials: CB
authors.lastname: Johnbeck
authors.affiliation: Department of Surgical Gastroenterology C & Department of Endocrinology, Rigshospitalet, Copenhagen, Denmark; and.
authors.forename: Ulrich
authors.initials: U
authors.lastname: Knigge
authors.affiliation: Department of Oncology, Rigshospitalet, Copenhagen, Denmark.
authors.forename: Seppo W
authors.initials: SW
authors.lastname: Langer
authors.affiliation: Department of Clinical Physiology, Nuclear Medicine & PET, Rigshospitalet & Cluster for Molecular Imaging, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Jann
authors.initials: J
authors.lastname: Mortensen
authors.affiliation: Department of Clinical Physiology, Nuclear Medicine & PET, Rigshospitalet & Cluster for Molecular Imaging, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Peter
authors.initials: P
authors.lastname: Oturai
authors.affiliation: Department of Clinical Physiology, Nuclear Medicine & PET, Rigshospitalet & Cluster for Molecular Imaging, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Annika
authors.initials: A
authors.lastname: Loft
authors.affiliation: Department of Clinical Physiology, Nuclear Medicine & PET, Rigshospitalet & Cluster for Molecular Imaging, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Anne Mette
authors.initials: AM
authors.lastname: Hag
authors.affiliation: Department of Clinical Physiology, Nuclear Medicine & PET, Rigshospitalet & Cluster for Molecular Imaging, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Andreas
authors.initials: A
authors.lastname: Kjær
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001011:Aorta / Q000000981:diagnostic imaging; D001158:Arteries / Q000000981:diagnostic imaging*; D050197:Atherosclerosis / Q000000981:diagnostic imaging*; D015992:Body Mass Index; D002118:Calcium / Q000378:metabolism; D002318:Cardiovascular Diseases / Q000000981:diagnostic imaging / Q000453:epidemiology; D003331:Coronary Vessels / Q000378:metabolism; D003920:Diabetes Mellitus / Q000000981:diagnostic imaging; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D008875:Middle Aged; D018358:Neuroendocrine Tumors / Q000000981:diagnostic imaging; D015282:Octreotide / Q000031:analogs & derivatives*; D009942:Organometallic Compounds; D049268:Positron-Emission Tomography; D019275:Radiopharmaceuticals; D012307:Risk Factors; D012907:Smoking / Q000009:adverse effects
chemical_list: C575629:64Cu-DOTATATE; C499142:Ga(III)-DOTATOC; D009942:Organometallic Compounds; D019275:Radiopharmaceuticals; D015282:Octreotide; D002118:Calcium
keywords: PET/CT; atherosclerosis; macrophages; molecular imaging; somatostatin receptor