title: Reproducibility of the kinetic analysis of 3'-deoxy-3'-[(18)F]fluorothymidine positron emission tomography in mouse tumor models.
abstract: OBJECTIVE
  We assessed the reproducibility of the kinetic analysis of 3'-deoxy-3'-[(18)F]fluorothymidine (FLT) positron emission tomography (PET) in A431 human epidermoid carcinoma and murine Lewis lung carcinoma (LLC) tumor models.
  
  
  METHODS
  We injected 7.4 MBq of FLT (n=10 for each group) and acquired 2-h dynamic PET images. A second scan was performed 1 day later. We calculated standardized uptake value (SUV), kinetic rate constants, volume of distribution of phosphorylated FLT (V(dm)), net influx constant (K(FLT-CA)) and influx constant by Patlak graphical analysis (K(FLT-PA)). The percent difference between measurements of a parameter was calculated to compare the reproducibilities of different parameters.
  
  
  RESULTS
  FLT phosphorylation was higher in mice with A431 tumors than in mice with LLC tumors (P<.005). Differences in the standard deviations of the percent differences of parameters were statistically significant (P<.001) in each model. In mice with A431 tumors, SUV, V(dm), K(FLT-CA) and K(FLT-PA) had standard deviations of the percent difference of < or = 20%. The most reproducible parameter was K(FLT-PA), although the standard deviation (15.6%) was not statistically different from those of V(dm) (15.8%), K(FLT-CA) (17.5%) and SUV (18.9%). In mice with LLC tumors, K(1), K(1)/k(2) and k(3) had standard deviations of the percent difference of < or = 20%. No macroparameters reflecting a total FLT flux had standard deviations of < or = 20%.
  
  
  CONCLUSIONS
  Our results show the reproducibility of the kinetic macroparameters of FLT PET in mouse tumors with high FLT phosphorylation.
authors.affiliation: Department of Nuclear Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul 138-736, South Korea.
authors.forename: Seung Jin
authors.initials: SJ
authors.lastname: Choi
authors.forename: Seog Young
authors.initials: SY
authors.lastname: Kim
authors.forename: Su Jin
authors.initials: SJ
authors.lastname: Kim
authors.forename: Jae Sung
authors.initials: JS
authors.lastname: Lee
authors.forename: Sang Ju
authors.initials: SJ
authors.lastname: Lee
authors.forename: Soo Ah
authors.initials: SA
authors.lastname: Park
authors.forename: Seung Jin
authors.initials: SJ
authors.lastname: Lee
authors.forename: Sung-Cheol
authors.initials: SC
authors.lastname: Yun
authors.forename: Ki Chun
authors.initials: KC
authors.lastname: Im
authors.forename: Seung Jun
authors.initials: SJ
authors.lastname: Oh
authors.forename: Sang-We
authors.initials: SW
authors.lastname: Kim
authors.forename: Jae Seung
authors.initials: JS
authors.lastname: Kim
authors.forename: Jin Sook
authors.initials: JS
authors.lastname: Ryu
authors.forename: Dae Hyuk
authors.initials: DH
authors.lastname: Moon
mesh_terms: D000818:Animals; D018827:Carcinoma, Lewis Lung / Q000000981:diagnostic imaging*; D002294:Carcinoma, Squamous Cell / Q000000981:diagnostic imaging*; D045744:Cell Line, Tumor; D015224:Dideoxynucleosides; D004195:Disease Models, Animal; D006801:Humans; D007700:Kinetics; D008297:Male; D051379:Mice; D015588:Observer Variation; D049268:Positron-Emission Tomography / Q000379:methods*; D015203:Reproducibility of Results
chemical_list: D015224:Dideoxynucleosides; C002854:alovudine