@article{WernerBeykanHiguchietal.2016, author = {Werner, Rudolf A. and Beykan, Seval and Higuchi, Takahiro and L{\"u}ckerath, Katharina and Weich, Alexander and Scheurlen, Michael and Bluemel, Christina and Herrmann, Ken and Buck, Andreas K. and Lassmann, Michael and Lapa, Constantin and H{\"a}nscheid, Heribert}, title = {The impact of \(^{177}\)Lu-octreotide therapy on \(^{99m}\)Tc-MAG3 clearance is not predictive for late nephropathy}, series = {Oncotarget}, volume = {7}, journal = {Oncotarget}, number = {27}, doi = {10.18632/oncotarget.9775}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-177318}, pages = {41233-41241}, year = {2016}, abstract = {Peptide Receptor Radionuclide Therapy (PRRT) for the treatment of neuroendocrine tumors may lead to kidney deterioration. This study aimed to evaluate the suitability of \(^{99m}\)Tc-mercaptoacetyltriglycine (\(^{99m}\)Tc-MAG3) clearance for the early detection of PRRT-induced changes on tubular extraction (TE). TE rate (TER) was measured prior to 128 PRRT cycles (7.6±0.4 GBq \(^{177}\)Lu-octreotate/octreotide each) in 32 patients. TER reduction during PRRT was corrected for age-related decrease and analyzed for the potential to predict loss of glomerular filtration (GF). The GF rate (GFR) as measure for renal function was derived from serum creatinine. The mean TER was 234 ± 53 ml/min/1.73 m² before PRRT (baseline) and 221 ± 45 ml/min/1.73 m² after a median follow-up of 370 days. The age-corrected decrease (mean: -3\%, range: -27\% to +19\%) did not reach significance (p=0.09) but significantly correlated with the baseline TER (Spearman p=-0.62, p<0.001). Patients with low baseline TER showed an improved TER after PRRT, high decreases were only observed in individuals with high baseline TER. Pre-therapeutic TER data were inferior to plasma creatinine-derived GFR estimates in predicting late nephropathy. TER assessed by \(^{99m}\)Tc-MAG3­clearance prior to and during PRRT is not suitable as early predictor of renal injury and an increased risk for late nephropathy.}, language = {en} } @article{WernerWeichHiguchietal.2017, author = {Werner, Rudolf A. and Weich, Alexander and Higuchi, Takahiro and Schmid, Jan S. and Schirbel, Andreas and Lassmann, Michael and Wild, Vanessa and Rudelius, Martina and Kudlich, Theodor and Herrmann, Ken and Scheurlen, Michael and Buck, Andreas K. and Kropf, Saskia and Wester, Hans-J{\"u}rgen and Lapa, Constantin}, title = {Imaging of Chemokine Receptor 4 Expression in Neuroendocrine Tumors - a Triple Tracer Comparative Approach}, series = {Theranostics}, volume = {7}, journal = {Theranostics}, number = {6}, doi = {10.7150/thno.18754}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-158008}, pages = {1489-1498}, year = {2017}, abstract = {C-X-C motif chemokine receptor 4 (CXCR4) and somatostatin receptors (SSTR) are overexpressed in gastro-entero-pancreatic neuroendocrine tumors (GEP-NET). In this study, we aimed to elucidate the feasibility of non-invasive CXCR4 positron emission tomography/computed tomography (PET/CT) imaging in GEP-NET patients using [\(^{68}\)Ga]Pentixafor in comparison to \(^{68}\)Ga-DOTA-D-Phe-Tyr3-octreotide ([\(^{68}\)Ga]DOTATOC) and \(^{18}\)F-fluorodeoxyglucose ([\(^{18}\)F]FDG). Twelve patients with histologically proven GEP-NET (3xG1, 4xG2, 5xG3) underwent [\(^{68}\)Ga]DOTATOC, [\(^{18}\)F]FDG, and [\(^{68}\)Ga]Pentixafor PET/CT for staging and planning of the therapeutic management. Scans were analyzed on a patient as well as on a lesion basis and compared to immunohistochemical staining patterns of CXCR4 and somatostatin receptors SSTR2a and SSTR5. [\(^{68}\)Ga]Pentixafor visualized tumor lesions in 6/12 subjects, whereas [\(^{18}\)F]FDG revealed sites of disease in 10/12 and [\(^{68}\)Ga]DOTATOC in 11/12 patients, respectively. Regarding sensitivity, SSTR-directed PET was the superior imaging modality in all G1 and G2 NET. CXCR4-directed PET was negative in all G1 NET. In contrast, 50\% of G2 and 80\% of G3 patients exhibited [\(^{68}\)Ga]Pentixafor-positive tumor lesions. Whereas CXCR4 seems to play only a limited role in detecting well-differentiated NET, increasing receptor expression could be non-invasively observed with increasing tumor grade. Thus, [\(^{68}\)Ga]Pentixafor PET/CT might serve as non-invasive read-out for evaluating the possibility of CXCR4-directed endoradiotherapy in advanced dedifferentiated SSTR-negative tumors.}, subject = {Positronen-Emissions-Tomografie}, language = {en} } @article{LapaHerrmannSchirbeletal.2017, author = {Lapa, Constantin and Herrmann, Ken and Schirbel, Andreas and H{\"a}nscheid, Heribert and L{\"u}ckerath, Katharina and Schottelius, Margret and Kircher, Malte and Werner, Rudolf A. and Schreder, Martin and Samnick, Samuel and Kropf, Saskia and Knop, Stefan and Buck, Andreas K. and Einsele, Hermann and Wester, Hans-Juergen and Kort{\"u}m, K. Martin}, title = {CXCR4-directed endoradiotherapy induces high response rates in extramedullary relapsed multiple myeloma}, series = {Theranostics}, volume = {7}, journal = {Theranostics}, number = {6}, doi = {10.7150/thno.19050}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-172095}, pages = {1589-1597}, year = {2017}, abstract = {C-X-C-motif chemokine receptor 4 (CXCR4) is a key factor for tumor growth and metastasis in several types of human cancer. We have recently reported promising first-in-man experience with CXCR4-directed endoradiotherapy (ERT) in multiple myeloma (MM). Eight heavily pretreated MM patients underwent a total of 10 ERT cycles (7 patients with 1 cycle and a single patient with 3 cycles). ERT was administered in combination with chemotherapy and autologous stem cell support. End points were occurrence and timing of adverse events, progression-free and overall survival. ERT was overall well tolerated without any unexpected acute adverse events or changes in vital signs. With absorbed tumor doses >30-70 Gy in intra- or extramedullary lesions, significant anti-myeloma activity was observed with 1 patient achieving complete remission and 5/8 partial remission. Directly after ERT major infectious complications were seen in one patient who died from sepsis 22 days after ERT, another patient with high tumor burden experienced lethal tumor lysis syndrome. Median progression-free survival was 54 days (range, 13-175), median overall survival was 223 days (range, 13-313). During follow-up (6 patients available), one patient died from infectious complications, 2/8 from disease progression, the remaining 3/8 patients are still alive. CXCR4-directed ERT was well-tolerated and exerted anti-myeloma activity even at very advanced stage MM with presence of extramedullary disease. Further assessment of this novel treatment option is highly warranted.}, language = {en} } @article{WernerSolnesJavadietal.2018, author = {Werner, Rudolf and Solnes, Lilja and Javadi, Mehrbod and Weich, Alexander and Gorin, Michael and Pienta, Kenneth and Higuchi, Takahiro and Buck, Andreas and Pomper, Martin and Rowe, Steven and Lapa, Constantin}, title = {SSTR-RADS Version 1.0 as a Reporting System for SSTR-PET Imaging and Selection of Potential PRRT Candidates: A Proposed Standardization Framework}, series = {Journal of Nuclear Medicine}, journal = {Journal of Nuclear Medicine}, issn = {0161-5505}, doi = {10.2967/jnumed.117.206631}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-161298}, year = {2018}, abstract = {Reliable standards and criteria for somatostatin receptor (SSTR) positron emission tomography (PET) are still lacking. We herein propose a structured reporting system on a 5-point scale for SSTR-PET imaging, titled SSTR-RADS version 1.0, which might serve as a standardized assessment for both diagnosis and treatment planning in neuroendocrine tumors (NET). SSTR-RADS could guide the imaging specialist in interpreting SSTR-PET scans, facilitate communication with the referring clinician so that appropriate work-up for equivocal findings is pursued, and serve as a reliable tool for patient selection for planned Peptide Receptor Radionuclide Therapy.}, subject = {Standardisierung}, language = {en} } @article{WernerBundschuhBundschuhetal.2018, author = {Werner, Rudolf A. and Bundschuh, Ralph A. and Bundschuh, Lena and Javadi, Mehrbod S. and Higuchi, Takahiro and Weich, Alexander and Sheikhbahaei, Sara and Pienta, Kenneth J. and Buck, Andreas K. and Pomper, Martin G. and Gorin, Michael A. and Lapa, Constantin and Rowe, Steven P.}, title = {MI-RADS: Molecular Imaging Reporting and Data Systems - A Generalizable Framework for Targeted Radiotracers with Theranostic Implications}, series = {Annals of Nuclear Medicine}, journal = {Annals of Nuclear Medicine}, issn = {0914-7187}, doi = {10.1007/s12149-018-1291-7}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-166995}, year = {2018}, abstract = {Both prostate-specific membrane antigen (PSMA)- and somatostatin receptor (SSTR)-targeted positron emission tomography (PET) imaging agents for staging and restaging of prostate carcinoma or neuroendocrine tumors, respectively, are seeing rapidly expanding use. In addition to diagnostic applications, both classes of radiotracers can be used to triage patients for theranostic endoradiotherapy. While interpreting PSMA- or SSTR-targeted PET/computed tomography (CT) scans, the reader has to be aware of certain pitfalls. Adding to the complexity of the interpretation of those imaging agents, both normal biodistribution, and also false-positive and -negative findings differ between PSMA- and SSTR-targeted PET radiotracers. Herein summarized under the umbrella term molecular imaging reporting and data systems (MI-RADS), two novel RADS classifications for PSMA- and SSTR-targeted PET imaging are described (PSMA- and SSTR-RADS). Both framework systems may contribute to increase the level of a reader's confidence and to navigate the imaging interpreter through indeterminate lesions, so that appropriate workup for equivocal findings can be pursued. Notably, PSMA- and SSTR-RADS are structured in a reciprocal fashion, i.e. if the reader is familiar with one system, the other system can readily be applied as well. In the present review we will discuss the most common pitfalls on PSMA- and SSTR-targeted PET/CT, briefly introduce PSMA- and SSTR-RADS, and define a future role of the umbrella framework MI-RADS compared to other harmonization systems.}, subject = {Positronen-Emissions-Tomografie}, language = {en} } @article{WernerWeichKircheretal.2018, author = {Werner, Rudolf A. and Weich, Alexander and Kircher, Malte and Solnes, Lilja B. and Javadi, Mehrbod S. and Higuchi, Takahiro and Buck, Andreas K. and Pomper, Martin G. and Rowe, Steven and Lapa, Constantin}, title = {The theranostic promise for neuroendocrine tumors in the late 2010s - Where do we stand, where do we go?}, series = {Theranostics}, volume = {8}, journal = {Theranostics}, number = {22}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-170264}, pages = {6088-6100}, year = {2018}, abstract = {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.}, subject = {Positronen-Emissions-Tomografie}, language = {en} } @unpublished{WernerBundschuhBundschuhetal.2019, author = {Werner, Rudolf A. and Bundschuh, Ralph A. and Bundschuh, Lena and Fanti, Stefano and Javadi, Mehrbod S. and Higuchi, Takahiro and Weich, A. and Pienta, Kenneth J. and Buck, Andreas K. and Pomper, Martin G. and Gorin, Michael A. and Herrmann, Ken and Lapa, Constantin and Rowe, Steven P.}, title = {Novel Structured Reporting Systems for Theranostic Radiotracers}, series = {Journal of Nuclear Medicine}, journal = {Journal of Nuclear Medicine}, issn = {0161-5505}, doi = {10.2967/jnumed.118.223537}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-174629}, year = {2019}, abstract = {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.}, subject = {Positronen-Emissions-Tomografie}, language = {en} } @article{FroehlichSerflingHiguchietal.2021, author = {Fr{\"o}hlich, Matthias and Serfling, Sebastian and Higuchi, Takahiro and Pomper, Martin G. and Rowe, Steven P. and Schmalzing, Marc and Tony, Hans-Peter and Gernert, Michael and Strunz, Patrick-Pascal and Portegys, Jan and Schwaneck, Eva-Christina and Gadeholt, Ottar and Weich, Alexander and Buck, Andreas K. and Bley, Thorsten A. and Guggenberger, Konstanze V. and Werner, Rudolf A.}, title = {Whole-Body [\(^{18}\)F]FDG PET/CT Can Alter Diagnosis in Patients with Suspected Rheumatic Disease}, series = {Diagnostics}, volume = {11}, journal = {Diagnostics}, number = {11}, issn = {2075-4418}, doi = {10.3390/diagnostics11112073}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-250227}, year = {2021}, abstract = {The 2-deoxy-d-[\(^{18}\)F]fluoro-D-glucose (FDG) positron emission tomography/computed tomography (PET/CT) is widely utilized to assess the vascular and articular inflammatory burden of patients with a suspected diagnosis of rheumatic disease. We aimed to elucidate the impact of [\(^{18}\)F]FDG PET/CT on change in initially suspected diagnosis in patients at the time of the scan. Thirty-four patients, who had undergone [\(^{18}\)F]FDG PET/CT, were enrolled and the initially suspected diagnosis prior to [18F]FDG PET/CT was compared to the final diagnosis. In addition, a semi-quantitative analysis including vessel wall-to-liver (VLR) and joint-to-liver (JLR) ratios was also conducted. Prior to [\(^{18}\)F]FDG PET/CT, 22/34 (64.7\%) of patients did not have an established diagnosis, whereas in 7/34 (20.6\%), polymyalgia rheumatica (PMR) was suspected, and in 5/34 (14.7\%), giant cell arteritis (GCA) was suspected by the referring rheumatologists. After [\(^{18}\)F]FDG PET/CT, the diagnosis was GCA in 19/34 (55.9\%), combined GCA and PMR (GCA + PMR) in 9/34 (26.5\%) and PMR in the remaining 6/34 (17.6\%). As such, [\(^{18}\)F]FDG PET/CT altered suspected diagnosis in 28/34 (82.4\%), including in all unclear cases. VLR of patients whose final diagnosis was GCA tended to be significantly higher when compared to VLR in PMR (GCA, 1.01 ± 0.08 (95\%CI, 0.95-1.1) vs. PMR, 0.92 ± 0.1 (95\%CI, 0.85-0.99), p = 0.07), but not when compared to PMR + GCA (1.04 ± 0.14 (95\%CI, 0.95-1.13), p = 1). JLR of individuals finally diagnosed with PMR (0.94 ± 0.16, (95\%CI, 0.83-1.06)), however, was significantly increased relative to JLR in GCA (0.58 ± 0.04 (95\%CI, 0.55-0.61)) and GCA + PMR (0.64 ± 0.09 (95\%CI, 0.57-0.71); p < 0.0001, respectively). In individuals with a suspected diagnosis of rheumatic disease, an inflammatory-directed [\(^{18}\)F]FDG PET/CT can alter diagnosis in the majority of the cases, particularly in subjects who were referred because of diagnostic uncertainty. Semi-quantitative assessment may be helpful in establishing a final diagnosis of PMR, supporting the notion that a quantitative whole-body read-out may be useful in unclear cases.}, language = {en} } @article{KosmalaSerflingDreheretal.2022, author = {Kosmala, Aleksander and Serfling, Sebastian E. and Dreher, Niklas and Lindner, Thomas and Schirbel, Andreas and Lapa, Constantin and Higuchi, Takahiro and Buck, Andreas K. and Weich, Alexander and Werner, Rudolf A.}, title = {Associations between normal organs and tumor burden in patients imaged with fibroblast activation protein inhibitor-directed positron emission tomography}, series = {Cancers}, volume = {14}, journal = {Cancers}, number = {11}, issn = {2072-6694}, doi = {10.3390/cancers14112609}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-275154}, year = {2022}, abstract = {(1) Background: We aimed to quantitatively investigate [\(^{68}\)Ga]Ga-FAPI-04 uptake in normal organs and to assess a relationship with the extent of FAPI-avid tumor burden. (2) Methods: In this single-center retrospective analysis, thirty-four patients with solid cancers underwent a total of 40 [\(^{68}\)Ga]Ga-FAPI-04 PET/CT scans. Mean standardized uptake values (SUV\(_{mean}\)) for normal organs were established by placing volumes of interest (VOIs) in the heart, liver, spleen, pancreas, kidneys, and bone marrow. Total tumor burden was determined by manual segmentation of tumor lesions with increased uptake. For tumor burden, quantitative assessment included maximum SUV (SUV\(_{max}\)), tumor volume (TV), and fractional tumor activity (FTA = TV × SUV\(_{mean}\)). Associations between uptake in normal organs and tumor burden were investigated by applying Spearman's rank correlation coefficient. (3) Results: Median SUV\(_{mean}\) values were 2.15 in the pancreas (range, 1.05-9.91), 1.42 in the right (range, 0.57-3.06) and 1.41 in the left kidney (range, 0.73-2.97), 1.2 in the heart (range, 0.46-2.59), 0.86 in the spleen (range, 0.55-1.58), 0.65 in the liver (range, 0.31-2.11), and 0.57 in the bone marrow (range, 0.26-0.94). We observed a trend towards significance for uptake in the myocardium and tumor-derived SUV\(_{max}\) (ρ = 0.29, p = 0.07) and TV (ρ = -0.30, p = 0.06). No significant correlation was achieved for any of the other organs: SUV\(_{max}\) (ρ ≤ 0.1, p ≥ 0.42), TV (ρ ≤ 0.11, p ≥ 0.43), and FTA (ρ ≤ 0.14, p ≥ 0.38). In a sub-analysis exclusively investigating patients with high tumor burden, significant correlations of myocardial uptake with tumor SUV\(_{max}\) (ρ = 0.44; p = 0.03) and tumor-derived FTA with liver uptake (ρ = 0.47; p = 0.02) were recorded. (4) Conclusions: In this proof-of-concept study, quantification of [\(^{68}\)Ga]Ga-FAPI-04 PET showed no significant correlation between normal organs and tumor burden, except for a trend in the myocardium. Those preliminary findings may trigger future studies to determine possible implications for treatment with radioactive FAP-targeted drugs, as higher tumor load or uptake may not lead to decreased doses in the majority of normal organs.}, language = {en} } @article{SerflingLapaDreheretal.2022, author = {Serfling, Sebastian E. and Lapa, Constantin and Dreher, Niklas and Hartrampf, Philipp E. and Rowe, Steven P. and Higuchi, Takahiro and Schirbel, Andreas and Weich, Alexander and Hahner, Stefanie and Fassnacht, Martin and Buck, Andreas K. and Werner, Rudolf A.}, title = {Impact of tumor burden on normal organ distribution in patients imaged with CXCR4-targeted [\(^{68}\)Ga]Ga-PentixaFor PET/CT}, series = {Molecular Imaging and Biology}, volume = {24}, journal = {Molecular Imaging and Biology}, number = {4}, doi = {10.1007/s11307-022-01717-1}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-324622}, pages = {659-665}, year = {2022}, abstract = {Background CXCR4-directed positron emission tomography/computed tomography (PET/CT) has been used as a diagnostic tool in patients with solid tumors. We aimed to determine a potential correlation between tumor burden and radiotracer accumulation in normal organs. Methods Ninety patients with histologically proven solid cancers underwent CXCR4-targeted [\(^{68}\)Ga]Ga-PentixaFor PET/CT. Volumes of interest (VOIs) were placed in normal organs (heart, liver, spleen, bone marrow, and kidneys) and tumor lesions. Mean standardized uptake values (SUV\(_{mean}\)) for normal organs were determined. For CXCR4-positive tumor burden, maximum SUV (SUV\(_{max}\)), tumor volume (TV), and fractional tumor activity (FTA, defined as SUV\(_{mean}\) x TV), were calculated. We used a Spearman's rank correlation coefficient (ρ) to derive correlative indices between normal organ uptake and tumor burden. Results Median SUV\(_{mean}\) in unaffected organs was 5.2 for the spleen (range, 2.44 - 10.55), 3.27 for the kidneys (range, 1.52 - 17.4), followed by bone marrow (1.76, range, 0.84 - 3.98), heart (1.66, range, 0.88 - 2.89), and liver (1.28, range, 0.73 - 2.45). No significant correlation between SUV\(_{max}\) in tumor lesions (ρ ≤ 0.189, P ≥ 0.07), TV (ρ ≥ -0.204, P ≥ 0.06) or FTA (ρ ≥ -0.142, P ≥ 0.18) with the investigated organs was found. Conclusions In patients with solid tumors imaged with [\(^{68}\)Ga]Ga-PentixaFor PET/CT, no relevant tumor sink effect was noted. This observation may be of relevance for therapies with radioactive and non-radioactive CXCR4-directed drugs, as with increasing tumor burden, the dose to normal organs may remain unchanged.}, language = {en} }