RT Journal Article
SR Electronic
T1 Tumor Localization of 16β-18F-Fluoro-5α-Dihydrotestosterone Versus 18F-FDG in Patients with Progressive, Metastatic Prostate Cancer
JF Journal of Nuclear Medicine
JO J Nucl Med
FD Society of Nuclear Medicine
SP 366
OP 373
VO 45
IS 3
A1 Larson, Steven M.
A1 Morris, Michael
A1 Gunther, Ilonka
A1 Beattie, Brad
A1 Humm, John L.
A1 Akhurst, Timothy A.
A1 Finn, Ronald D.
A1 Erdi, Yusuf
A1 Pentlow, Keith
A1 Dyke, Jon
A1 Squire, Olivia
A1 Bornmann, William
A1 McCarthy, Timothy
A1 Welch, Michael
A1 Scher, Howard
YR 2004
UL http://jnm.snmjournals.org/content/45/3/366.abstract
AB This trial was an initial assessment of the feasibility, in vivo targeting, and biokinetics of 16β-18F-fluoro-5α-dihydrotestosterone (18F-FDHT) PET in patients with metastatic prostate cancer to assess androgen receptor expression. Methods: Seven patients with progressive clinically metastatic prostate cancer underwent 18F-FDG and 18F-FDHT PET scans in addition to conventional imaging methods. Three patients had their studies repeated 1 mo later, 2 while on testosterone therapy, and the third after treatment with 17-allylamino-17-demethoxygeldanamycin (17-AAG). High-pressure liquid radiochromatography was used to separate 18F-FDHT from radiolabeled metabolites. Lesion-by-lesion comparisons between the 18F-FDHT, 18F-FDG, and conventional imaging methods were performed. Results: Metabolism of 18F-FDHT was rapid, with 80% conversion within 10 min to radiolabeled metabolites that circulated bound to plasma proteins. Tumor uptake was rapid and tumor retention was prolonged. Fifty-nine lesions were identified by conventional imaging methods. 18F-FDG PET was positive in 57 of 59 lesions (97%), with an average lesion maximum standardized uptake value (SUVmax) = 5.22. 18F-FDHT PET was positive in 46 of 59 lesions (78%), with the average positive lesion SUVmax = 5.28. Treatment with testosterone resulted in diminished 18F-FDHT uptake at the tumor site. Conclusion: 18F-FDHT localizes to tumor sites in patients with progressive clinically metastatic prostate cancer and may be a promising agent to analyze antigen receptors and their impact on the clinical management of prostate cancer.