title: An experimental study on O-[18F]fluoromethyl-L-tyrosine for differentiation between tumor and inflammatory tissues.
abstract: OBJECTIVE
  O-[18F]fluoromethyl-L-tyrosine (18F-FMT) is a recently developed tumor-detecting agent with simple preparation and high radiochemical yields. The aim of this study was to assess the potency of 18F-FMT for differentiating tumor and inflammatory tissues using an animal model with an implanted tumor and experimentally induced inflammatory foci.
  
  
  METHODS
  An ascites hepatoma cell line, AH109A, turpentine oil and Staphylococcus aureus were inoculated subcutaneously into Donryu rats as a tumor model, aseptic inflammation model and bacterial infection model, respectively. The biodistribution of radioactivity was assessed in rats at 5, 10, 30, 60, and 120 min after injection with 18F-FMT. Dual tracer whole-body and macro autoradiographies were performed 60 min after injection with a mixture of 18F-FMT and 2-deoxy-D-[1-14C]glucose (14C-DG).
  
  
  RESULTS
  Tumor uptake of 18F-FMT was on average 1.27% injected dose per gram of tissue (%ID/g) and 1.43% ID/g at 30 min and 60 min, respectively and significantly higher than that in other normal tissues, except the pancreas (3.48% ID/g at 60 min). The uptakes in the aseptic and bacterial inflammatory tissues were very low and were not different from those of the background tissues. Dual tracer whole-body and macro autoradiographic studies showed that tumor uptake of 18F-FMT was clearly higher than uptake by the other tissues, while 18F-FMT accumulated much less both in aseptic and bacterial inflammatory tissues. In contrast, the 14C-DG images showed high accumulations not only in tumors but also in aseptic and bacterial inflammatory tissues.
  
  
  CONCLUSIONS
  18F-FMT seems to be a promissing tracer for the differentiation between tumor and inflammation because of higher specificity to tumor.
authors.affiliation: Division of Nuclear Medicine, Cyclotron and Radioisotope Center, Tohoku University, Aoba, Aramaki, Aoba, Sendai, Miyagi 980-8578, Japan. manami@cyric.tohoku.ac.jp
authors.forename: Manami
authors.initials: M
authors.lastname: Suzuki
authors.forename: Keiichiro
authors.initials: K
authors.lastname: Yamaguchi
authors.forename: Go
authors.initials: G
authors.lastname: Honda
authors.forename: Ren
authors.initials: R
authors.lastname: Iwata
authors.forename: Shozo
authors.initials: S
authors.lastname: Furumoto
authors.forename: Myeong-Gi
authors.initials: MG
authors.lastname: Jeong
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Fukuda
authors.forename: Masatoshi
authors.initials: M
authors.lastname: Itoh
mesh_terms: D000818:Animals; D006528:Carcinoma, Hepatocellular / Q000000981:diagnostic imaging* / Q000378:metabolism*; D003937:Diagnosis, Differential; D004353:Drug Evaluation, Preclinical; D008297:Male; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals / Q000493:pharmacokinetics; D051381:Rats; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013203:Staphylococcal Infections / Q000000981:diagnostic imaging* / Q000378:metabolism*; D014443:Tyrosine / Q000031:analogs & derivatives* / Q000493:pharmacokinetics
chemical_list: C493093:O-(18F)fluoromethyl-L-tyrosine; D019275:Radiopharmaceuticals; D014443:Tyrosine