A Comparative Study of the @entity519 PET Tracers @entity26641 , XXXX , and @entity9241 in a Preclinical Tumor Model.

@entity35 @entity15436 @entity5 @entity9241 @entity26 @entity15437 @entity26641 @entity519 @entity980 @entity4571
PURPOSE: Several individual clinical and preclinical studies have shown the possibility of evaluating @entity5 by using noninvasive positron emission tomography (PET). The current study compared 3 @entity519 PET tracers frequently used in the clinic, @entity9241 , @entity15437 , and @entity26641 , in a preclinical @entity5 model. Tracer uptake was evaluated for the optimal time point for imaging, @entity5 ( @entity5 ), spatial reproducibility, and sensitivity to @entity26 modification. METHODS AND MATERIALS: PET/computed tomography (CT) images of @entity980 R1-bearing WAG/Rij @entity35 were acquired at multiple time points post injection (p.i.) with one of the @entity519 tracers. @entity5 values were calculated, and reproducibility was investigated by voxel-to-voxel analysis, represented as correlation coefficients (R) or Dice similarity coefficient of the high-uptake volume. Tumor @entity26 modifications were induced by exposure to either @entity15436 / @entity4571 treatment or 7% @entity26 breathing. RESULTS: @entity5 was stabilized and maximal at 2 hours p.i. for @entity15437 (4.0    0.5) and at 3 hours p.i. for @entity26641 (7.2    0.7), whereas @entity9241 showed a constant increasing @entity5 (9.0    0.8 at 6 hours p.i.). High spatial reproducibility was observed by voxel-to-voxel comparisons and Dice similarity coefficient calculations on the 30% highest uptake volume for both @entity9241 (R = 0.86; Dice coefficient = 0.76) and @entity26641 (R = 0.76; Dice coefficient = 0.70), whereas @entity15437 was less reproducible (R = 0.52; Dice coefficient = 0.49). Modifying the @entity519 fraction resulted in enhanced mean standardized uptake values for both @entity26641 and @entity15437 upon 7% @entity26 breathing. Only @entity9241 uptake was found to be reversible upon exposure to @entity4571 and @entity15436 . CONCLUSIONS: This study indicates that each tracer has its own strengths and, depending on the question to be answered, a different tracer can be put forward.
