Background: [F-18]HX4 is a promising new PET tracer developed to identify hypoxic areas in tumor tissue. This study analyzes [F-18]HX4 kinetics and assesses the performance of simplified methods for quantification of [F-18]HX4 uptake. To this end, eight patients with non-small cell lung cancer received dynamic PET scans at three different time points (0, 120, and 240 min) after injection of 426 +/- 72 MBq [F-18]HX4, each lasting 30 min. Several compartment models were fitted to time activity curves (TAC) derived from various areas within tumor tissue using image-derived input functions.
Results: Best fits were obtained using the reversible two-tissue compartment model with blood volume parameter (2T4k+V-B). Simplified measures correlated well with V-T estimates (tumor-to-blood ratio (TBr) R-2 = 0.96, tumor-to-muscle ratio R-2 = 0.94, standardized uptake value R-2 = 0.89).
Conclusions: [F-18]HX4 shows reversible kinetics in tumor tissue: 2T4k+V-B. TBr based on static imaging at 2 or 4 h can be used for quantification of [F-18]HX4 uptake.
- F-18-3-Fluoro-2-(4-((2-Nitro-1H-Imidazol-1-yl)Methyl)-1H-1,2,3-Triazol-1-yl) Propan-1-ol ([F-18]HX4)
- Molecular imaging
- Positron emission tomography (PET)
- Non-small cell lung cancer (NSCLC)
- Tracer kinetic modeling
- Standardized uptake value (SUV)
- Tumor-to-blood ratio
- Image-derived input function (IDIF)