%0 Journal Article
%A Dietlein, Felix
%A Kobe, Carsten
%A Neubauer, Stephan
%A Stockter, Simone
%A Fischer, Thomas
%A Schomäcker, Klaus
%A Heidenreich, Axel
%A Zlatopolskiy, Boris D.
%A Neumaier, Bernd
%A Drzezga, Alexander
%A Dietlein, Markus
%A Schmidt, M.
%T PSA-Stratified Performance of $^{18}$F- and $^{68}$Ga-PSMA PET in Patients with Biochemical Recurrence of Prostate Cancer
%J Journal of nuclear medicine
%V 58
%N 6
%@ 2159-662X
%C New York, NY
%I Soc.
%M FZJ-2017-05481
%P 947 - 952
%D 2017
%X Several studies outlined the sensitivity of 68Ga-labeled PET tracers against the prostate-specific membrane antigen (PSMA) for localization of relapsed prostate cancer in patients with renewed increase in the prostate-specific antigen (PSA), commonly referred to as biochemical recurrence. Labeling of PSMA tracers with 18F offers numerous advantages, including improved image resolution, longer half-life, and increased production yields. The aim of this study was to assess the PSA-stratified performance of the 18F-labeled PSMA tracer 18F-DCFPyL and the 68Ga-labeled reference 68Ga-PSMA-HBED-CC. Methods: We examined 191 consecutive patients with biochemical recurrence according to standard acquisition protocols using 18F-DCFPyL (n = 62, 269.8 MBq, PET scan at 120 min after injection) or 68Ga-PSMA-HBED-CC (n = 129, 158.9 MBq, 60 min after injection). We determined PSA-stratified sensitivity rates for both tracers and corrected our calculations for Gleason scores using iterative matched-pair analyses. As an orthogonal validation, we directly compared tracer distribution patterns in a separate cohort of 25 patients, sequentially examined with both tracers. Results: After prostatectomy (n = 106), the sensitivity of both tracers was significantly associated with absolute PSA levels (P = 4.3 × 10−3). Sensitivity increased abruptly, when PSA values exceeded 0.5 μg/L (P = 2.4 × 10−5). For a PSA less than 3.5 μg/L, most relapses were diagnosed at a still limited stage (P = 3.4 × 10−6). For a PSA of 0.5–3.5 μg/L, PSA-stratified sensitivity was 88% (15/17) for 18F-DCFPyL and 66% (23/35) for 68Ga-PSMA-HBED-CC. This significant difference was preserved in the Gleason-matched-pair analysis. Outside of this range, sensitivity was comparably low (PSA < 0.5 μg/L) or high (PSA > 3.5 μg/L). After radiotherapy (n = 85), tracer sensitivity was largely PSA-independent. In the 25 patients examined with both tracers, distribution patterns of 18F-DCFPyL and 68Ga-PSMA-HBED-CC were strongly comparable (P = 2.71 × 10−8). However, in 36% of the PSMA-positive patients we detected additional lesions on the 18F-DCFPyL scan (P = 3.7 × 10−2). Conclusion: Our data suggest that 18F-DCFPyL is noninferior to 68Ga-PSMA-HBED-CC, while offering the advantages of 18F labeling. Our results indicate that imaging with 18F-DCFPyL may even exhibit improved sensitivity in localizing relapsed tumors after prostatectomy for moderately increased PSA levels. Although the standard acquisition protocols, used for 18F-DCFPyL and 68Ga-PSMA-HBED-CC in this study, stipulate different activity doses and tracer uptake times after injection, our findings provide a promising rationale for validation of 18F-DCFPyL in future prospective trials.
%F PUB:(DE-HGF)16
%9 Journal Article
%U <Go to ISI:>//WOS:000402572500021
%$ pmid:27908968
%R 10.2967/jnumed.116.185538
%U https://juser.fz-juelich.de/record/836360