PT - JOURNAL ARTICLE AU - NagaVaraKishore Pillarsetty AU - Blesida Punzalan AU - Steven M. Larson TI - 2-<sup>18</sup>F-Fluoropropionic Acid as a PET Imaging Agent for Prostate Cancer AID - 10.2967/jnumed.109.064212 DP - 2009 Oct 01 TA - Journal of Nuclear Medicine PG - 1709--1714 VI - 50 IP - 10 4099 - http://jnm.snmjournals.org/content/50/10/1709.short 4100 - http://jnm.snmjournals.org/content/50/10/1709.full SO - J Nucl Med2009 Oct 01; 50 AB - There is a high interest in developing an 18F-labeled PET tracer that can aid in diagnosis and therapy monitoring of prostate cancer. In the current study, we have evaluated the potential of 2-18F-fluoropropionic acid (18F-FPA) as a PET tracer for imaging prostate cancer. Methods: 18F-FPA was synthesized starting from methyl-2-bromopropionate. Small-animal PET studies were performed on mice with CWR22rv1, PC-3, DU-145, and LNCaP prostate xenografts, and comparison of imaging characteristics of 18F-FPA with 18F-FDG uptake is reported. Biodistribution studies with 18F-FPA were performed on mice with CWR22rv1 xenografts and compared with 14C-acetate. Results: 18F-FPA was synthesized in 44% overall radiochemical yield (decay-corrected). Small-animal PET studies revealed that 18F-FPA can delineate both androgen-dependent and androgen-independent prostate xenografts with high tumor-to-background ratios. Comparative imaging studies demonstrate the superior performance of 18F-FPA over 18F-FDG for imaging prostate cancer, with excellent tumor-to-background contrast. Biodistribution studies show that tumor uptake of the tracer was 5.52 ± 0.35, 5.53 ± 0.42, 5.74 ± 0.54, and 5.34 ± 0.19 percentage injected dose (%ID) per gram at 1, 2, 3, and 4 h, respectively, after injection. The %ID/g values for 18F-FPA and 14C-acetate 1 h after tail vein injection were 7.08 ± 0.80 and 0.36 ± 0.08 in tumor, and the corresponding tumor-to-muscle ratios were 1.94 and 2.06, respectively. Conclusion: The data presented here indicate that 18F-FPA accumulates in prostate cancers with high tumor-to-background ratios. 18F-FPA has potential for use in the clinical diagnosis of prostate cancer in humans.