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 (KFLT), blood to tissue transport (K1), and phosphorylation (k3). FDG-PET scans were obtained 75-90 min postinjection. Results: KFLT and k3, but not K1 or k3/k2+k3, 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: KFLT (flux) appears to distinguish recurrence from radionecrosis better than other parameters, FLT and FDG semiquantitative approaches, or visual analysis of images of either tracer.
- Positron emission tomography (PET)
- Proliferation imaging
ASJC Scopus subject areas
- Radiology Nuclear Medicine and imaging
- Cancer Research