TY - JOUR
A1 - Breun, Maria
A1 - Monoranu, Camelia M.
A1 - Kessler, Almuth F.
A1 - Matthies, Cordula
A1 - Löhr, Mario
A1 - Hagemann, Carsten
A1 - Schirbel, Andreas
A1 - Rowe, Steven P.
A1 - Pomper, Martin G.
A1 - Buck, Andreas K.
A1 - Wester, Hans-Jürgen
A1 - Ernestus, Ralf-Ingo
A1 - Lapa, Constantin
T1 - [\(^{68}\)Ga]-Pentixafor PET/CT for CXCR4-mediated imaging of vestibular schwannomas
JF - Frontiers in Oncology
N2 - We have recently demonstrated CXCR4 overexpression in vestibular schwannomas (VS). This study investigated the feasibility of CXCR4-directed positron emission tomography/computed tomography (PET/CT) imaging of VS using the radiolabeled chemokine ligand [\(^{68}\)Ga]Pentixafor.
Methods: 4 patients with 6 primarily diagnosed or pre-treated/observed VS were enrolled. All subjects underwent [\(^{68}\)Ga]Pentixafor PET/CT prior to surgical resection. Images were analyzed visually and semi-quantitatively for CXCR4 expression including calculation of tumor-to-background ratios (TBR). Immunohistochemistry served as standard of reference in three patients.
Results: [\(^{68}\)Ga]Pentixafor PET/CT was visually positive in all cases. SUV\(_{mean}\) and SUV\(_{max}\) were 3.0 ± 0.3 and 3.8 ± 0.4 and TBR\(_{mean}\) and TBR\(_{max}\) were 4.0 ± 1.4 and 5.0 ± 1.7, respectively. Histological analysis confirmed CXCR4 expression in tumors.
Conclusion: Non-invasive imaging of CXCR4 expression using [\(^{68}\)Ga]Pentixafor PET/CT of VS is feasible and could prove useful for in vivo assessment of CXCR4 expression.
KW - vestibular schwannoma
KW - CXCR4
KW - PET/CT
KW - molecular imaging
KW - Pentixafor
Y1 - 2019
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-201863
VL - 9
IS - 503
ER -
TY - JOUR
A1 - Chen, Xinyu
A1 - Werner, Rudolf A.
A1 - Koshino, Kazuhiro
A1 - Nose, Naoko
A1 - Mühlig, Saskia
A1 - Rowe, Steven P.
A1 - Pomper, Martin G.
A1 - Lapa, Constantin
A1 - Decker, Michael
A1 - Higuchi, Takahiro
T1 - Molecular Imaging-Derived Biomarker of Cardiac Nerve Integrity - Introducing High NET Affinity PET Probe \(^{18}\)F-AF78
JF - Theranostics
N2 - Background: Radiolabeled agents that are substrates for the norepinephrine transporter (NET) can be used to quantify cardiac sympathetic nervous conditions and have been demonstrated to identify high-risk congestive heart failure (HF) patients prone to arrhythmic events. We aimed to fully characterize the kinetic profile of the novel \(^{18}\)F-labeled NET probe AF78 for PET imaging of the cardiac sympathetic nervous system (SNS) among various species.
Methods: \(^{18}\)F-AF78 was compared to norepinephrine (NE) and established SNS radiotracers by employing in vitro cell assays, followed by an in vivo PET imaging approach with healthy rats, rabbits and nonhuman primates (NHPs). Additionally, chase protocols were performed in NHPs with NET inhibitor desipramine (DMI) and the NE releasing stimulator tyramine (TYR) to investigate retention kinetics in cardiac SNS.
Results: Relative to other SNS radiotracers, 18F-AF78 showed higher transport affinity via NET in a cell-based competitive uptake assay (IC\(^{50}\) 0.42 ± 0.14 µM), almost identical to that of NE (IC\(^{50}\), 0.50 ± 0.16 µM, n.s.). In rabbits and NHPs, initial cardiac uptake was significantly reduced by NET inhibition. Furthermore, cardiac tracer retention was not affected by a DMI chase protocol but was markedly reduced by intermittent TYR chase, thereby suggesting that \(^{18}\)F-AF78 is stored and can be released via the synaptic vesicular turnover process. Computational modeling hypothesized the formation of a T-shaped π-π stacking at the binding site, suggesting a rationale for the high affinity of \(^{18}\)F-AF78.
Conclusion: \(^{18}\)F-AF78 demonstrated high in vitro NET affinity and advantageous in vivo radiotracer kinetics across various species, indicating that \(^{18}\)F-AF78 is an SNS imaging agent with strong potential to guide specific interventions in cardiovascular medicine.
KW - norepinephrine transporter
KW - T-shaped π-π stacking
KW - nonhuman primates
KW - radiotracer kinetics
KW - cardiac innervation imaging
KW - sympathetic nervous system
Y1 - 2022
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-300685
VL - 12
IS - 9
SP - 4446
EP - 4458
ER -
TY - JOUR
A1 - Eissler, Cristoph
A1 - Werner, Rudolf A.
A1 - Arias-Loza, Paula
A1 - Nose, Naoko
A1 - Chen, Xinyu
A1 - Pomper, Martin G.
A1 - Rowe, Steven P.
A1 - Lapa, Constantin
A1 - Buck, Andreas K.
A1 - Higuchi, Takahiro
T1 - The number of frames on ECG-gated \(^{18}\)F-FDG small animal PET has a significant impact on LV systolic and diastolic functional parameters
JF - Molecular Imaging
N2 - Objectives. This study is aimed at investigating the impact of frame numbers in preclinical electrocardiogram- (ECG-) gated \(^{18}\)F-fluorodeoxyglucose (\(^{18}\)F-FDG) positron emission tomography (PET) on systolic and diastolic left ventricular (LV) parameters in rats. Methods. \(^{18}\)F-FDG PET imaging using a dedicated small animal PET system with list mode data acquisition and continuous ECG recording was performed in diabetic and control rats. The list-mode data was sorted and reconstructed with different numbers of frames (4, 8, 12, and 16) per cardiac cycle into tomographic images. Using an automatic ventricular edge detection software, left ventricular (LV) functional parameters, including ejection fraction (EF), end-diastolic (EDV), and end-systolic volume (ESV), were calculated. Diastolic variables (time to peak filling (TPF), first third mean filling rate (1/3 FR), and peak filling rate (PFR)) were also assessed. Results. Significant differences in multiple parameters were observed among the reconstructions with different frames per cardiac cycle. EDV significantly increased by numbers of frames (353.8 & PLUSMN; 57.7 mu l*, 380.8 & PLUSMN; 57.2 mu l*, 398.0 & PLUSMN; 63.1 mu l*, and 444.8 & PLUSMN; 75.3 mu l at 4, 8, 12, and 16 frames, respectively; *P < 0.0001 vs. 16 frames), while systolic (EF) and diastolic (TPF, 1/3 FR and PFR) parameters were not significantly different between 12 and 16 frames. In addition, significant differences between diabetic and control animals in 1/3 FR and PFR in 16 frames per cardiac cycle were observed (P < 0.005), but not for 4, 8, and 12 frames. Conclusions. Using ECG-gated PET in rats, measurements of cardiac function are significantly affected by the frames per cardiac cycle. Therefore, if you are going to compare those functional parameters, a consistent number of frames should be used.
KW - Myocardial-perfusion SPECT
KW - left-ventricular function
KW - ejection fraction
KW - MRI
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-265778
VL - 2021
ER -
TY - JOUR
A1 - Matsusaka, Yohji
A1 - Chen, Xinyu
A1 - Arias-Loza, Paula
A1 - Werner, Rudolf A.
A1 - Nose, Naoko
A1 - Sasaki, Takanori
A1 - Rowe, Steven P.
A1 - Pomper, Martin G.
A1 - Lapa, Constantin
A1 - Higuchi, Takahiro
T1 - In Vivo Functional Assessment of Sodium-Glucose Cotransporters (SGLTs) Using [\(^{18}\)F]Me4FDG PET in Rats
JF - Molecular Imaging
N2 - Background. Mediating glucose absorption in the small intestine and renal clearance, sodium glucose cotransporters (SGLTs) have emerged as an attractive therapeutic target in diabetic patients. A substantial fraction of patients, however, only achieve inadequate glycemic control. Thus, we aimed to assess the potential of the SGLT-targeting PET radiotracer alpha-methyl-4-deoxy-4-[\(^{18}\)F]fluoro-D-glucopyranoside ([\(^{18}\)F]Me4FDG) as a noninvasive intestinal and renal biomarker of SGLT-mediated glucose transport. Methods. We investigated healthy rats using a dedicated small animal PET system. Dynamic imaging was conducted after administration of the reference radiotracer 2-deoxy-2-[\(^{18}\)F]fluoro-D-glucose ([\(^{18}\)F]FDG), or the SGLT-targeting agent, [\(^{18}\)F]Me4FDG either directly into the digestive tract (for assessing intestinal absorption) or via the tail vein (for evaluating kidney excretion). To confirm the specificity of [18F]Me4FDG and responsiveness to treatment, a subset of animals was also pretreated with the SGLT inhibitor phlorizin. In this regard, an intraintestinal route of administration was used to assess tracer absorption in the digestive tract, while for renal assessment, phlorizin was injected intravenously (IV). Results. Serving as reference, intestinal administration of [\(^{18}\)F]FDG led to slow absorption with retention of % of administered radioactivity at 15 min. [\(^{18}\)F]Me4FDG, however, was rapidly absorbed into the blood and cleared from the intestine within 15 min, leading to markedly lower tracer retention of % (). Intraintestinal phlorizin led to marked increase of [\(^{18}\)F]Me4FDG uptake (15 min, %; vs. untreated controls), supporting the notion that this PET agent can measure adequate SGLT inhibition in the digestive tract. In the kidneys, radiotracer was also sensitive to SGLT inhibition. After IV injection, [\(^{18}\)F]Me4FDG reabsorption in the renal cortex was significantly suppressed by phlorizin when compared to untreated animals (%ID/g at 60 min, vs. untreated controls, ; ). Conclusion. As a noninvasive read-out of the concurrent SGLT expression in both the digestive tract and the renal cortex, [\(^{18}\)F]Me4FDG PET may serve as a surrogate marker for treatment response to SGLT inhibition. As such, [\(^{18}\)F]Me4FDG may enable improvement in glycemic control in diabetes by PET-based monitoring strategies.
KW - Sodium-Glucose Cotransporters (SGLTs)
KW - diabetes
KW - rats
Y1 - 2022
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-300708
VL - 2022
ER -
TY - JOUR
A1 - Toyama, Yoshitaka
A1 - Werner, Rudolf A.
A1 - Ruiz-Bedoya, Camilo A.
A1 - Ordonez, Alvaro A.
A1 - Takase, Kei
A1 - Lapa, Constantin
A1 - Jain, Sanjay K.
A1 - Pomper, Martin G.
A1 - Rowe, Steven P.
A1 - Higuchi, Takahiro
T1 - Current and future perspectives on functional molecular imaging in nephro-urology: theranostics on the horizon
JF - Theranostics
N2 - In recent years, a paradigm shift from single-photon-emitting radionuclide radiotracers toward positron-emission tomography (PET) radiotracers has occurred in nuclear oncology. Although PET-based molecular imaging of the kidneys is still in its infancy, such a trend has emerged in the field of functional renal radionuclide imaging. Potentially allowing for precise and thorough evaluation of renal radiotracer urodynamics, PET radionuclide imaging has numerous advantages including precise anatomical co-registration with CT images and dynamic three-dimensional imaging capability. In addition, relative to scintigraphic approaches, PET can allow for significantly reduced scan time enabling high-throughput in a busy PET practice and further reduces radiation exposure, which may have a clinical impact in pediatric populations. In recent years, multiple renal PET radiotracers labeled with C-11, Ga-68, and F-18 have been utilized in clinical studies. Beyond providing a precise non-invasive read-out of renal function, such radiotracers may also be used to assess renal inflammation. This manuscript will provide an overview of renal molecular PET imaging and will highlight the transformation of conventional scintigraphy of the kidneys toward novel, high-resolution PET imaging for assessing renal function. In addition, future applications will be introduced, e.g. by transferring the concept of molecular image-guided diagnostics and therapy (theranostics) to the field of nephrology.
KW - glomerular filtration rate
KW - renal
KW - kidney
KW - renal function
KW - positron emission tomography
KW - nephrology
KW - urology
KW - molecular imaging
KW - theranostics
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-260090
VL - 11
IS - 12
ER -
TY - JOUR
A1 - Weich, Alexander
A1 - Higuchi, Takahiro
A1 - Bundschuh, Ralph A.
A1 - Lapa, Constantin
A1 - Serfling, Sebastian E.
A1 - Rowe, Steven P.
A1 - Pomper, Martin G.
A1 - Herrmann, Ken
A1 - Buck, Andreas K.
A1 - Derlin, Thorsten
A1 - Werner, Rudolf A.
T1 - Training on reporting and data system (RADS) for somatostatin-receptor targeted molecular imaging can reduce the test anxiety of inexperienced readers
JF - Molecular Imaging and Biology
N2 - Purpose
For somatostatin receptor (SSTR)-positron emission tomography/computed tomography (PET/CT), a standardized framework termed SSTR-reporting and data system (RADS) has been proposed. We aimed to elucidate the impact of a RADS-focused training on reader’s anxiety to report on SSTR-PET/CT, the motivational beliefs in learning such a system, whether it increases reader’s confidence, and its implementation in clinical routine.
Procedures
A 3-day training course focusing on SSTR-RADS was conducted. Self-report questionnaires were handed out prior to the course (Pre) and thereafter (Post). The impact of the training on the following categories was evaluated: (1) test anxiety to report on SSTR-PET/CT, (2) motivational beliefs, (3) increase in reader’s confidence, and (4) clinical implementation. To assess the effect size of the course, Cohen’s d was calculated (small, d = 0.20; large effect, d = 0.80).
Results
Of 22 participants, Pre and Post were returned by 21/22 (95.5%). In total, 14/21 (66.7%) were considered inexperienced (IR, < 1 year experience in reading SSTR-PET/CTs) and 7/21 (33.3%) as experienced readers (ER, > 1 year). Applying SSTR-RADS, a large decrease in anxiety to report on SSTR-PET/CT was noted for IR (d = − 0.74, P = 0.02), but not for ER (d = 0.11, P = 0.78). For the other three categories motivational beliefs, reader’s confidence, and clinical implementation, agreement rates were already high prior to the training and persisted throughout the course (P ≥ 0.21).
Conclusions
A framework-focused reader training can reduce anxiety to report on SSTR-PET/CTs, in particular for inexperienced readers. This may allow for a more widespread adoption of this system, e.g., in multicenter trials for better intra- and interindividual comparison of scan results.
KW - PET/CT
KW - neuroendocrine tumor
KW - PRRT
KW - peptide receptor radionuclide therapy
KW - reporting and data system
KW - SSTR-RADS
KW - RADS
Y1 - 2022
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-324645
VL - 24
IS - 4
ER -
TY - JOUR
A1 - Weich, Alexander
A1 - Werner, Rudolf A.
A1 - Buck, Andreas K.
A1 - Hartrampf, Philipp E.
A1 - Serfling, Sebastian E.
A1 - Scheurlen, Michael
A1 - Wester, Hans-Jürgen
A1 - Meining, Alexander
A1 - Kircher, Stefan
A1 - Higuchi, Takahiro
A1 - Pomper, Martin G.
A1 - Rowe, Steven P.
A1 - Lapa, Constantin
A1 - Kircher, Malte
T1 - CXCR4-Directed PET/CT in Patients with Newly Diagnosed Neuroendocrine Carcinomas
JF - Diagnostics
N2 - We aimed to elucidate the diagnostic potential of the C-X-C motif chemokine receptor 4 (CXCR4)-directed positron emission tomography (PET) tracer \(^{68}\)Ga-Pentixafor in patients with poorly differentiated neuroendocrine carcinomas (NEC), relative to the established reference standard \(^{18}\)F-FDG PET/computed tomography (CT). In our database, we retrospectively identified 11 treatment-naïve patients with histologically proven NEC, who underwent \(^{18}\)F-FDG and CXCR4-directed PET/CT for staging and therapy planning. The images were analyzed on a per-patient and per-lesion basis and compared to immunohistochemical staining (IHC) of CXCR4 from PET-guided biopsies. \(^{68}\)Ga-Pentixafor visualized tumor lesions in 10/11 subjects, while \(^{18}\)F-FDG revealed sites of disease in all 11 patients. Although weak to moderate CXCR4 expression could be corroborated by IHC in 10/11 cases, \(^{18}\)F-FDG PET/CT detected significantly more tumor lesions (102 vs. 42; total lesions, n = 107; p < 0.001). Semi-quantitative analysis revealed markedly higher 18F-FDG uptake as compared to \(^{68}\)Ga-Pentixafor (maximum and mean standardized uptake values (SUV) and tumor-to-background ratios (TBR) of cancerous lesions, SUVmax: 12.8 ± 9.8 vs. 5.2 ± 3.7; SUVmean: 7.4 ± 5.4 vs. 3.1 ± 3.2, p < 0.001; and, TBR 7.2 ± 7.9 vs. 3.4 ± 3.0, p < 0.001). Non-invasive imaging of CXCR4 expression in NEC is inferior to the reference standard \(^{18}\)F-FDG PET/CT.
KW - CXCR4
KW - NET
KW - NEC
KW - 68Ga-Pentixafor
KW - 18F-FDG
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-234231
SN - 2075-4418
VL - 11
IS - 4
ER -
TY - INPR
A1 - Werner, Rudolf A.
A1 - Andree, Christian
A1 - Javadi, Mehrbod S.
A1 - Lapa, Constantin
A1 - Buck, Andreas K.
A1 - Higuchi, Takahiro
A1 - Pomper, Martin G.
A1 - Gorin, Michael A.
A1 - Rowe, Steven P.
A1 - Pienta, Kenneth J.
T1 - A Voice From the Past: Re-Discovering the Virchow Node with PSMA-targeted \(^{18}\)F-DCFPyL PET Imaging
T2 - Urology - The Gold Journal
N2 - No abstract available.
KW - 18F-DCFPyL
KW - Virchow Node
KW - PSMA-PET
KW - Virchow Node
KW - Positron Emission Tomography
KW - Prostate Cancer
KW - PET
Y1 - 2018
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-161103
SN - 0090-4295
N1 - This is the accepted manuscript of Rudolf Werner, Christian Andree, Mehrbod S. Javadi, Constantin Lapa, Andreas K. Buck, Takahiro Higuchi, Martin G. Pomper, Michael A.Gorin, Steven P.Rowe, Kenneth J. Pienta: A Voice From the Past: Re-Discovering the Virchow Node with PSMA-Targeted 18F-DCFPyL PET Imaging. Published in Urology 117(2018), p. 18-21. https://doi.org/10.1016/j.urology.2018.03.030
N1 - Die finale Version dieses Artikels steht unter https://doi.org/10.1016/j.urology.2018.03.030 oder https://nbn-resolving.org/urn:nbn:de:bvb:20-opus-164632 open access zur Verfügung.
ER -
TY - JOUR
A1 - Werner, Rudolf A.
A1 - Andree, Christian
A1 - Javadi, Mehrbod S.
A1 - Lapa, Constantin
A1 - Buck, Andreas K.
A1 - Higuchi, Takahiro
A1 - Pomper, Martin G.
A1 - Gorin, Michael A.
A1 - Rowe, Steven P.
A1 - Pienta, Kenneth J.
T1 - A Voice From the Past: Re-Discovering the Virchow Node with PSMA-targeted \(^{18}\)F-DCFPyL PET Imaging
JF - Urology - The Gold Journal
N2 - No abstract available.
KW - 18F-DCFPyL
KW - PET
KW - PSMA-PET
KW - Positron Emission Tomography
KW - Prostate Cancer
KW - Virchow Node
Y1 - 2018
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-164632
SN - 0090-4295
VL - 117
ER -
TY - INPR
A1 - Werner, Rudolf A.
A1 - Bundschuh, Ralph A.
A1 - Bundschuh, Lena
A1 - Fanti, Stefano
A1 - Javadi, Mehrbod S.
A1 - Higuchi, Takahiro
A1 - Weich, A.
A1 - Pienta, Kenneth J.
A1 - Buck, Andreas K.
A1 - Pomper, Martin G.
A1 - Gorin, Michael A.
A1 - Herrmann, Ken
A1 - Lapa, Constantin
A1 - Rowe, Steven P.
T1 - Novel Structured Reporting Systems for Theranostic Radiotracers
T2 - Journal of Nuclear Medicine
N2 - Standardized reporting is more and more routinely implemented in clinical practice and such structured reports have a major impact on a large variety of medical fields, e.g. laboratory medicine, pathology, and, recently, radiology. Notably, the field of nuclear medicine is constantly evolving, as novel radiotracers for numerous clinical applications are developed. Thus, framework systems for standardized reporting in this field may a) increase clinical acceptance of new radiotracers, b) allow for inter- and intra-center comparisons for quality assurance, and c) may be used in (global) multi-center studies to ensure comparable results and enable efficient data abstraction. In the last two years, several standardized framework systems for positron emission tomography (PET) radiotracers with potential theranostic applications have been proposed. These include systems for prostate-specific membrane antigen (PSMA)-targeted PET agents for the diagnosis and treatment of prostate cancer (PCa) and somatostatin receptor (SSTR)-targeted PET agents for the diagnosis and treatment of neuroendocrine neoplasias. In the present review, those standardized framework systems for PSMA- and SSTR-targeted PET will be briefly introduced followed by an overview of their advantages and limitations. In addition, potential applications will be defined, approaches to validate such concepts will be proposed, and future perspectives will be discussed.
KW - standardized reporting
KW - Positronen-Emissions-Tomografie
KW - prostate cancer
KW - neuroendocrine neoplasia
KW - 68Ga-DOTATATE
KW - 68Ga-DOTATOC
KW - 68Ga-DOTANOC
KW - somatostatin receptor
KW - SSTR
KW - prostate-specific membrane antigen
KW - PSMA
KW - RADS
KW - PSMA-RADS
KW - SSTR-RADS
KW - MI-RADS
KW - PROMISE
Y1 - 2019
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-174629
SN - 0161-5505
N1 - This research was originally published in JNM. Authors: Rudolf A. Werner, Ralph A. Bundschuh, Lena Bundschuh, Stefano Fanti, Mehrbod S. Javadi, Takahiro Higuchi, A. Weich, Kenneth J. Pienta, Andreas K. Buck, Martin G. Pomper, Michael A. Gorin, Ken Herrmann, Constantin Lapa, Steven P. Rowe. Novel Structured Reporting Systems for Theranostic Radiotracers. J Nucl Med May 1, 2019 vol. 60 no. 5 577-584 © SNMMI.
ER -