title: PET imaging of hepatocellular carcinoma with 18F-fluoroethylcholine and 11C-choline.
abstract: OBJECTIVE
  Choline-based radiotracers have been studied for PET imaging of hepatocellular carcinoma (HCC). Using an (18)F-labeled choline analog, instead of the (11)C-labeled native choline, would facilitate its widespread use in the clinic. In this study, PET with (18)F-fluoroethylcholine (FEC) and (11)C-choline (CHOL) were compared using an animal model of HCC. The effects of fasting on the performance of choline-based tracers were also investigated.
  
  
  METHODS
  A woodchuck model of HCC was used to compare the two tracers, which were administered and imaged in sequence during the same imaging session. Dynamic PET images were generated spanning 50 min starting from tracer injection. Time-activity curves and tracer contrast were calculated in liver regions with tracer accumulation, and the contrast at a late time-point with the two tracers, and between fasted and nonfasted states, were compared.
  
  
  RESULTS
  Foci of HCC with increased uptake ranged in size from 1.0 to 1.6 cm, with mean tumor-to-background contrast of 1.3 with FEC and 1.5 with CHOL at 50 min after injection. The tracers show similar patterns of uptake immediately following administration, and both activities plateaued at 10 min after injection. No significant differences in uptake dynamics or final contrast were observed between the fasted and nonfasted states.
  
  
  CONCLUSIONS
  PET imaging of HCC is possible with both CHOL and FEC. Fasting was not found to affect accumulation of either tracer. These results encourage further investigation into the clinical utility of FEC for HCC imaging.
authors.affiliation: Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH 44106-7207, USA. jeffrey.kolthammer@case.edu
authors.forename: Jeffrey A
authors.initials: JA
authors.lastname: Kolthammer
authors.forename: David J
authors.initials: DJ
authors.lastname: Corn
authors.forename: Nathan
authors.initials: N
authors.lastname: Tenley
authors.forename: Chunying
authors.initials: C
authors.lastname: Wu
authors.forename: Haibin
authors.initials: H
authors.lastname: Tian
authors.forename: Yanming
authors.initials: Y
authors.lastname: Wang
authors.forename: Zhenghong
authors.initials: Z
authors.lastname: Lee
mesh_terms: D000818:Animals; D001692:Biological Transport; D002250:Carbon Radioisotopes; D006528:Carcinoma, Hepatocellular / Q000000981:diagnostic imaging* / Q000378:metabolism; D002794:Choline / Q000031:analogs & derivatives* / Q000378:metabolism; D005215:Fasting; D006801:Humans; D008113:Liver Neoplasms / Q000000981:diagnostic imaging* / Q000378:metabolism; D008392:Marmota; D049268:Positron-Emission Tomography / Q000379:methods*
chemical_list: D002250:Carbon Radioisotopes; C448902:fluoroethylcholine; D002794:Choline