TY  - JOUR
A1  - Werner, Rudolf A.
A1  - Sheikhbahaei, Sara
A1  - Jones, Krystyna M.
A1  - Javadi, Mehrbod S.
A1  - Solnes, Lilja B.
A1  - Ross, Ashley E.
A1  - Allaf, Mohamad E.
A1  - Pienta, Kenneth J.
A1  - Lapa, Constantin
A1  - Buck, Andreas K.
A1  - Higuchi, Takahiro
A1  - Pomper, Martin G.
A1  - Gorin, Micheal A.
A1  - Rowe, Steven P.
T1  - Patterns of uptake of prostate-specific membrane antigen (PSMA)-targeted \(^{18}\)F-DCFPyL in peripheral ganglia
JF  - Annals of Nuclear Medicine
N2  - Objective: Radiotracers targeting prostate-specific membrane antigen (PSMA) have increasingly been recognized as showing uptake in a number of normal structures, anatomic variants, and non-prostate-cancer pathologies. We aimed to explore the frequency and degree of uptake in peripheral ganglia in patients undergoing PET with the PSMA-targeted agent \(^{18}\)F-DCFPyL. 
Methods: A total of 98 patients who underwent \(^{18}\)F-DCFPyL PET/CT imaging were retrospectively analyzed. This included 76 men with prostate cancer (PCa) and 22 patients with renal cell carcinoma (RCC; 13 men, 9 women). Scans were evaluated for uptake in the cervical, stellate, celiac, lumbar and sacral ganglia. Maximum standardized uptake value corrected to body weight (SUV\(_{max}\)), and maximum standardized uptake value corrected to lean body mass (SUL\(_{max}\)) were recorded for all ganglia with visible uptake above background. Ganglia-to-background ratios were calculated by dividing the SUV\(_{max}\) and SUL\(_{max}\) values by the mean uptake in the ascending aorta (Aortamean) and the right gluteus muscle (Gluteusmean). 
Results: Overall, 95 of 98 (96.9%) patients demonstrated uptake in at least one of the evaluated peripheral ganglia. With regard to the PCa cohort, the most frequent sites of radiotracer accumulation were lumbar ganglia (55/76, 72.4%), followed by the cervical ganglia (51/76, 67.1%). Bilateral uptake was found in the majority of cases [lumbar 44/55 (80%) and cervical 30/51 (58.8%)]. Additionally, discernible radiotracer uptake was recorded in 50/76 (65.8%) of the analyzed stellate ganglia and in 45/76 (59.2%) of the celiac ganglia, whereas only 5/76 (6.6%) of the sacral ganglia demonstrated \(^{18}\)F-DCFPyL accumulation. Similar findings were observed for patients with RCC, with the most frequent locations of radiotracer uptake in both the lumbar (20/22, 90.9%) and cervical ganglia (19/ 22, 86.4%). No laterality preference was found in mean PSMA-ligand uptake for either the PCa or RCC cohorts. 
Conclusion: As PSMA-targeted agents become more widely disseminated, the patterns of uptake in structures that are not directly relevant to patients’ cancers must be understood. This is the first systematic evaluation of the uptake of \(^{18}\)F-DCFPyL in ganglia demonstrating a general trend with a descending frequency of radiotracer accumulation in lumbar, cervical, stellate, celiac, and sacral ganglia. The underlying biology that leads to variability of PSMA-targeted radiotracers in peripheral ganglia is not currently understood, but may provide opportunities for future research.
KW  - 18F-DCFPL
KW  - Positronen-Emissions-Tomografie
KW  - Prostata
KW  - PSMA
KW  - Ganglia
KW  - Pitfall
KW  - PET
KW  - Tracer
KW  - Radiotracer
KW  - Imaging pitfalls
KW  - Prostate Cancer
Y1  - 2017
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-166971
SN  - 0914-7187
VL  - 31
IS  - 9
ER  - 
TY  - JOUR
A1  - Werner, Rudolf A.
A1  - Weich, Alexander
A1  - Kircher, Malte
A1  - Solnes, Lilja B.
A1  - Javadi, Mehrbod S.
A1  - Higuchi, Takahiro
A1  - Buck, Andreas K.
A1  - Pomper, Martin G.
A1  - Rowe, Steven
A1  - Lapa, Constantin
T1  - The theranostic promise for neuroendocrine tumors in the late 2010s – Where do we stand, where do we go?
JF  - Theranostics
N2  - More than 25 years after the first peptide receptor radionuclide therapy (PRRT), the concept of somatostatin receptor (SSTR)-directed imaging and therapy for neuroendocrine tumors (NET) is seeing rapidly increasing use. To maximize the full potential of its theranostic promise, efforts in recent years have expanded recommendations in current guidelines and included the evaluation of novel theranostic radiotracers for imaging and treatment of NET. Moreover, the introduction of standardized reporting framework systems may harmonize PET reading, address pitfalls in interpreting SSTR-PET/CT scans and guide the treating physician in selecting PRRT candidates. Notably, the concept of PRRT has also been applied beyond oncology, e.g. for treatment of inflammatory conditions like sarcoidosis. Future perspectives may include the efficacy evaluation of PRRT compared to other common treatment options for NET, novel strategies for closer monitoring of potential side effects, the introduction of novel radiotracers with beneficial pharmacodynamic and kinetic properties or the use of supervised machine learning approaches for outcome prediction. This article reviews how the SSTR-directed theranostic concept is currently applied and also reflects on recent developments that hold promise for the future of theranostics in this context.
KW  - theranostics
KW  - Positronen-Emissions-Tomografie
KW  - PRRT
KW  - somatostatin receptor
KW  - peptide receptor radionuclide therapy
KW  - neuroendocrine tumor
Y1  - 2018
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-170264
VL  - 8
IS  - 22
ER  -