title: Meningiomas: a comparative study of 68Ga-DOTATOC, 68Ga-DOTANOC and 68Ga-DOTATATE for molecular imaging in mice.
abstract: OBJECTIVE
  The goal of this study was to compare the tumor uptake kinetics and diagnostic value of three (68)Ga-DOTA-labeled somatostatin analogues ((68)Ga-DOTATOC, (68)Ga-DOTANOC, and (68)Ga-DOTATATE) using PET/CT in a murine model with subcutaneous meningioma xenografts.
  
  
  METHODS
  The experiment was performed with 16 male NUDE NU/NU mice bearing xenografts of a human meningioma cell line (CH-157MN). (68)Ga-DOTATOC, (68)Ga-DOTANOC, and (68)Ga-DOTATATE were produced in a FASTLab automated platform. Imaging was performed on an Argus small-animal PET/CT scanner. The SUVmax of the liver and muscle, and the tumor-to-liver (T/L) and tumor-to-muscle (T/M) SUV ratios were computed. Kinetic analysis was performed using Logan graphical analysis for a two-tissue reversible compartmental model, and the volume of distribution (Vt) was determined.
  
  
  RESULTS
  Hepatic SUVmax and Vt were significantly higher with (68)Ga-DOTANOC than with (68)Ga-DOTATOC and (68)Ga-DOTATATE. No significant differences between tracers were found for SUVmax in tumor or muscle. No differences were found in the T/L SUV ratio between (68)Ga-DOTATATE and (68)Ga-DOTATOC, both of which had a higher fraction than (68)Ga-DOTANOC. The T/M SUV ratio was significantly higher with (68)Ga-DOTATATE than with (68)Ga-DOTATOC and (68)Ga-DOTANOC. The Vt for tumor was higher with (68)Ga-DOTATATE than with (68)Ga-DOTANOC and relatively similar to that of (68)Ga-DOTATOC.
  
  
  CONCLUSIONS
  This study demonstrates, for the first time, the ability of the three radiolabeled somatostatin analogues tested to image a human meningioma cell line. Although Vt was relatively similar with (68)Ga-DOTATATE and (68)Ga-DOTATOC, uptake was higher with (68)Ga-DOTATATE in the tumor than with (68)Ga-DOTANOC and (68)Ga-DOTATOC, suggesting a higher diagnostic value of (68)Ga-DOTATATE for detecting meningiomas.
authors.affiliation: Unidad de Medicina y Cirugía Experimental, Instituto de Investigación Sanitaria Gregorio Marañón, Madrid, Spain; Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Madrid, Spain.
authors.forename: María Luisa
authors.initials: ML
authors.lastname: Soto-Montenegro
authors.affiliation: Unidad de Medicina y Cirugía Experimental, Instituto de Investigación Sanitaria Gregorio Marañón, Madrid, Spain.
authors.forename: Santiago
authors.initials: S
authors.lastname: Peña-Zalbidea
authors.affiliation: Unidad de Medicina y Cirugía Experimental, Instituto de Investigación Sanitaria Gregorio Marañón, Madrid, Spain.
authors.forename: Jose María
authors.initials: JM
authors.lastname: Mateos-Pérez
authors.affiliation: Unidad de Aplicaciones Biomédicas y Farmacocinética, Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas (CIEMAT), Madrid, Spain.
authors.forename: Marta
authors.initials: M
authors.lastname: Oteo
authors.affiliation: Unidad de Aplicaciones Biomédicas y Farmacocinética, Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas (CIEMAT), Madrid, Spain.
authors.forename: Eduardo
authors.initials: E
authors.lastname: Romero
authors.affiliation: Unidad de Aplicaciones Biomédicas y Farmacocinética, Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas (CIEMAT), Madrid, Spain.
authors.forename: Miguel Ángel
authors.initials: MÁ
authors.lastname: Morcillo
authors.affiliation: Unidad de Medicina y Cirugía Experimental, Instituto de Investigación Sanitaria Gregorio Marañón, Madrid, Spain; Departamento de Bioingeniería e Ingeniería Aerospacial, Universidad Carlos III, Madrid, Spain.
authors.forename: Manuel
authors.initials: M
authors.lastname: Desco
mesh_terms: D000818:Animals; D006801:Humans; D008297:Male; D008577:Meningeal Neoplasms / Q000175:diagnosis*; D008579:Meningioma / Q000175:diagnosis*; D051379:Mice; D008819:Mice, Nude; D057054:Molecular Imaging; D015282:Octreotide / Q000031:analogs & derivatives*; D009942:Organometallic Compounds; D049268:Positron-Emission Tomography
chemical_list: C504894:68Ga-DOTANOC; C499142:Ga(III)-DOTATOC; D009942:Organometallic Compounds; C513399:gallium Ga 68 dotatate; D015282:Octreotide