NCI-sponsored trial for the evaluation of safety and preliminary efficacy of 3'-deoxy-3'-[18F]fluorothymidine (FLT) as a marker of proliferation in patients with recurrent gliomas: preliminary efficacy studies

Mol Imaging Biol. 2009 Sep-Oct;11(5):343-55. doi: 10.1007/s11307-009-0215-2. Epub 2009 Mar 27.


Purpose: 3'-Deoxy-3'-[18F]fluorothymidine ([18F]FLT) is being developed for imaging cellular proliferation. The goals were to explore the capacity of FLT-positron emission tomography (PET) to distinguish between recurrence and radionecrosis in gliomas and compare the results to those obtained with 2-fluoro-2-deoxy-D: -glucose (FDG).

Procedures: Fifteen patients with tumor recurrence and four with radionecrosis, determined by clinical course and magnetic resonance imaging results, were studied by dynamic [18F]FLT-PET with arterial blood sampling. A two-tissue compartment four-rate constant model was used to determine metabolic flux (K (FLT)), blood to tissue transport (K (1)), and phosphorylation (k (3)). FDG-PET scans were obtained 75-90 min postinjection.

Results: K (FLT) and k (3), but not K (1) or k (3)/k (2) + k (3), reached significance for separating the recurrence from radionecrosis groups. Standardized uptake value and visual analyses of FLT or FDG images did not reach significance.

Conclusions: K (FLT) (flux) appears to distinguish recurrence from radionecrosis better than other parameters, FLT and FDG semiquantitative approaches, or visual analysis of images of either tracer.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Adult
  • Brain Chemistry
  • Brain Neoplasms / diagnostic imaging*
  • Brain Neoplasms / metabolism
  • Brain Neoplasms / pathology
  • Cell Growth Processes / physiology
  • Diagnosis, Differential
  • Dideoxynucleosides* / pharmacokinetics
  • Female
  • Glioma / diagnostic imaging*
  • Glioma / metabolism
  • Glioma / pathology
  • Humans
  • Male
  • Middle Aged
  • Models, Biological
  • Necrosis
  • Neoplasm Recurrence, Local / diagnostic imaging*
  • Neoplasm Recurrence, Local / metabolism
  • Neoplasm Recurrence, Local / pathology
  • Positron-Emission Tomography / methods
  • Radiopharmaceuticals* / pharmacokinetics
  • Statistics, Nonparametric
  • Young Adult


  • Dideoxynucleosides
  • Radiopharmaceuticals
  • alovudine