@inproceedings{WernerHayakawaAriasLozaetal.2017,
  author    = {Werner, Rudolf and Hayakawa, Nobuyuki and Arias-Loza, Paula-Anah and Wakabayashi, Hiroshi and Shinaji, Tetsuya and Lapa, Constantin and Pelzer, Theo and Higuchi, Takahiro},
  title     = {Bildgebung der fr{\"u}hen linksventrikul{\"a}ren Dysfunktion mit ECG-gated F-18-FDG PET in einem Diabetes-Ratten-Modell},
  series = {Nuklearmedizin},
  volume    = {56},
  booktitle = {Nuklearmedizin},
  number    = {2},
  publisher = {Schattauer Verlag},
  issn      = {0029-5566},
  doi       = {10.3413/Nukmed-0880-17-02},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-161396},
  pages     = {Abstract Nr.: V119},
  year      = {2017},
  abstract  = {Einleitung: Die linksventrikul{\"a}re diastolische Dysfunktion (LVDD) ist bei Diabetikern noch vor Entwicklung einer klinisch apparenten Herzinsuffizienz eines der ersten Anzeichen einer kardialen Beteiligung. Daher soll in dieser Studie untersucht werden, ob die LVDD mit ECG-gated F-18-FDG PET in einem Diabetes-Rattenmodell dargestellt werden kann. Methodik: Es wurden F-18-FDG PET Scans in einem Typ-2-Diabetes Rattenmodell (ZDF fa/fa, n=6) und in ZL Kontrollen (n=6) vorgenommen (Alter, jeweils 13 Wochen). Unter Hyperinsulinemic-Euglycemic Clamp-Technik wurden 37 MBq 18F-FDG {\"u}ber die Schwanzvene appliziert. 15-35 Minuten nach Tracergabe wurden mittels eines Kleintier-PET-Scanners sowie unter EKG-Ableitung PET Scans angefertigt (16 frames/cardiac cycle). Die linksventrikul{\"a}re Ejektionsfraktion (EF) und die Peak F{\"u}llrate (PFR) wurden mittels einer geeigneten Software (Heart Function View) gemessen, wobei die Software an die Gr{\"o}ße des Rattenherzes angepasst wurde. Ergebnisse: Im Alter von 13 Wochen entwickeln ZDF Diabetes-Ratten eine im Vergleich zu Kontrolltieren eine signifikante myokardiale Hypertrophie, best{\"a}tigt durch post-mortem Analyse des Herzgewichtes (994±78mg vs. 871±44mg in ZDF Diabetes-Ratten vs. ZL Kontrollen, p<0.01). ECG-gated PET zeigte eine signifikante Abnahme der LV diastolischen PFR (10.4±0.5 vs. 11.8±0.4 EDV/sec in ZDF Diabetes-Ratten vs. ZL Kontrollen, p<0.001), jedoch zeigte sich kein signifikanter Unterschied zwischen LVEF und der Herzfrequenz in den untersuchten ZDF Diabetes-Ratten und Kontrollen (LVEF: 60.0±4.5 vs. 63.7±4.1\%, n.s. und HR: 305±25 vs. 323±24 bpm, n.s.). Schlussfolgerung: Im Diabetes-Ratten-Modell kann unter Verwendung eines ECG-gated FDG-PET Protokolls die diastolische Dysfunktion als Parameter der fr{\"u}hen diabetischen Kardiomyopathie nachgewiesen werden.},
  subject      = {Positronen-Emissions-Tomografie},
  language  = {de}
}
@article{WernerSchmidHiguchietal.2018,
  author    = {Werner, Rudolf and Schmid, Jan-Stefan and Higuchi, Takahiro and Javadi, Mehrbod S. and Rowe, Steven P. and M{\"a}rkl, Bruno and Aulmann, Christoph and Fassnacht, Martin and Kroiß, Matthias and Reiners, Christoph and Buck, Andreas and Kreissl, Michael and Lapa, Constantin},
  title     = {Predictive value of \(^{18}\)F-FDG PET in patients with advanced medullary thyroid carcinoma treated with vandetanib},
  series = {Journal of Nuclear Medicine},
  journal   = {Journal of Nuclear Medicine},
  issn      = {0161-5505},
  doi       = {10.2967/jnumed.117.199778},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-161256},
  year      = {2018},
  abstract  = {Introduction: Therapeutic options in advanced medullary thyroid carcinoma (MTC) have markedly improved since the introduction of tyrosine kinase inhibitors (TKI). We aimed to assess the role of metabolic imaging using 2-deoxy-2-(\(^{18}\)F)fluoro-D-glucose (\(^{18}\)F-FDG) positron emission tomography/computed tomography (PET/CT) shortly before and 3 months after initiation of TKI treatment. Methods: Eighteen patients with advanced and progressive MTC scheduled for vandetanib treatment underwent baseline \(^{18}\)F-FDG PET/CT prior to and 3 months after TKI treatment initiation. During follow-up, CT scans were performed every 3 months and analyzed according to Response Evaluation Criteria In Solid Tumors (RECIST). The predictive value for estimating progression-free (PFS) and overall survival (OS) was examined by investigating \(^{18}\)F-FDG mean/maximum standardized uptake values (SUVmean/max) of the metabolically most active lesion as well as by analyzing clinical parameters (tumor marker doubling times {calcitonin, carcinoembryonic antigen (CEA)}, prior therapies, RET (rearranged during transfection) mutational status, and disease type). Results: Within a median follow-up of 5.2 years, 9 patients experienced disease progression after a median time interval of 2.1y whereas the remainder had ongoing disease control (n=5 partial response and n=4 stable disease). Eight of the 9 patients with progressive disease died from MTC after a median of 3.5y after TKI initiation. Pre-therapeutic SUVmean >4.0 predicted a significantly shorter PFS (PFS: 1.9y vs. 5.2y; p=0.04). Furthermore, sustained high 18F-FDG uptake at 3 months with a SUVmean>2.8 tended to portend an unfavorable prognosis with a PFS of 1.9y (vs. 3.5y; p=0.3). Prolonged CEA doubling times were significantly correlated with longer PFS (r=0.7) and OS (r=0.76, p<0.01, respectively). None of the other clinical parameters had prognostic significance. Conclusions: Pre-therapeutic \(^{18}\)F-FDG PET/CT holds prognostic information in patients with advanced MTC scheduled for treatment with the TKI vandetanib. Low tumor metabolism of SUVmean < 4.0 prior to treatment predicts longer progression-free survival.},
  subject      = {Medull{\"a}rer Schilddr{\"u}senkrebs},
  language  = {en}
}
@article{WernerWakabyashiChenetal.2018,
  author    = {Werner, Rudolf and Wakabyashi, Hiroshi and Chen, Xinyu and Hirano, Mitsuru and Shinaji, Tetsuya and Lapa, Constantin and Rowe, Steven and Javadi, Mehrbod and Higuchi, Takahiro},
  title     = {Functional renal imaging with \(^{18}\)F-FDS PET in rat models of renal disorders},
  series = {Journal of Nuclear Medicine},
  journal   = {Journal of Nuclear Medicine},
  issn      = {0161-5505},
  doi       = {10.2967/jnumed.117.203828},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-161279},
  year      = {2018},
  abstract  = {Background: Precise regional quantitative assessment of renal function is limited with conventional \(^{99m}\)Tc-labeled renal radiotracers. A recent study reported that the positron emission tomography (PET) radiotracer 2-deoxy-2-(\(^{18}\)F-fluorosorbitol (\(^{18}\)F-FDS) has ideal pharmacokinetics for functional renal imaging. Furthermore, (\(^{18}\)F-FDS is available via simple reduction from routinely used 2-deoxy-2-(\(^{18}\)F-fluoro-D-glucose ((\(^{18}\)F-FDG). We aimed to further investigate the potential of (\(^{18}\)F-FDS PET as a functional renal imaging agent using rat models of kidney diseases. Methods: Two different rat models of renal impairment were investigated: Glycerol induced acute renal failure (ARF) by intramuscular administration of glycerol in hind legs and unilateral ureteral obstruction (UUO) by ligation of the left ureter. 24h after these treatments, dynamic 30 min 18F-FDS PET data were acquired using a dedicated small animal PET system. Urine 18F-FDS radioactivity 30 min after radiotracer injection was measured together with co-injected \(^{99m}\)Tc-diethylenetriaminepentaacetic acid (\(^{99m}\)Tc-DTPA) urine activity. Results: Dynamic PET imaging demonstrated rapid (\(^{18}\)F-FDS accumulation in the renal cortex and rapid radiotracer excretion via kidneys in control healthy rats. On the other hand, significantly delayed renal radiotracer uptake (continuous slow uptake) was observed in ARF rats and UUO-treated kidneys. Measured urine radiotracer concentrations of (\(^{18}\)F-FDS and \(^{99m}\)Tc-DTPA were well correlated (R=0.84, P<0.05). Conclusions: (\(^{18}\)F-FDS PET demonstrated favorable kinetics for functional renal imaging in rat models of kidney diseases. Advantages of high spatiotemporal resolution of PET imaging and simple tracer production could potentially complement or replace conventional renal scintigraphy in select cases and significantly improve the diagnostic performance of renal functional imaging.},
  subject      = {Nierenfunktionsst{\"o}rung},
  language  = {en}
}
@article{WernerKobayashiJavadietal.2018,
  author    = {Werner, Rudolf A. and Kobayashi, Ryohei and Javadi, Mehrbod Som and K{\"o}ck, Zoe and Wakabayashi, Hiroshi and Unterecker, Stefan and Nakajima, Kenichi and Lapa, Constantin and Menke, Andreas and Higuchi, Takahiro},
  title     = {Impact of Novel Antidepressants on Cardiac Metaiodobenzylguanidine (mIBG) Uptake: Experimental Studies in SK-N-SH Cells and Healthy Rabbits},
  series = {Journal of Nuclear Medicine},
  journal   = {Journal of Nuclear Medicine},
  issn      = {0161-5505},
  doi       = {10.2967/jnumed.117.206045},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-161280},
  year      = {2018},
  abstract  = {Background: \(^{123}\)I-metaiodobenzylguanidine (mIBG) provides independent prognostic value for risk stratification among heart failure patients, but the use of concomitant medication should not impact its quantitative information. We aimed to evaluate the four most-prescribed antidepressants currently used as a first‑line treatment for patients with major depressive disorder (MDD) and their potential on altering mIBG imaging results. Methods: The inhibition effect of four different types of antidepressants (desipramine, escitalopram, venlafaxine and bupropion) for MDD treatment on \(^{131}\)I-mIBG uptake was assessed by in-vitro cell uptake assays using human neuroblastoma SK-N-SH cells. The half maximal inhibitory concentration (IC50) of tracer uptake was determined from dose-response curves. To evaluate the effects of IV pretreatment with desipramine (1.5 mg/kg) and escitalopram (2.5, 15 mg/kg) on mIBG cardiac uptake, in-vivo planar 123I-mIBG scans in healthy New Zealand White Rabbits were conducted. Results: The IC50 values of desipramine, escitalopram, venlafaxine and bupropion on \(^{131}\)I-mIBG cellular uptake were 11.9 nM, 7.5 μM, 4.92 μM, and 12.9 μM, respectively. At the maximum serum concentration (Cmax, as derived by previous clinical trials), the inhibition rates of 131I-mIBG uptake were 90.6 \% for desipramine, 25.5 \% for venlafaxine, 11.7 \% for bupropion and 0.72 \% for escitalopram. A low inhibition rate for escitalopram in the cell uptake study triggered investigation of an in-vivo rabbit model: with dosage considerably higher than clinical practice, the non-inhibitory effect of escitalopram was confirmed. Furthermore, pretreatment with desipramine led to a marked reduction of cardiac 123I-mIBG uptake. Conclusions: In the present in-vitro binding assay and in-vivo rabbit study, the selective-serotonin reuptake inhibitor escitalopram had no major impact on neuronal cardiac mIBG uptake within therapeutic dose ranges, while other types of first-line antidepressants for MDD treatment led to a significant decrease. These preliminary results warrant further confirmatory clinical trials regarding the reliability of cardiac mIBG imaging, in particular, if the patient's neuropsychiatric status would not tolerate withdrawal of a potentially norepinephrine interfering antidepressant.},
  subject      = {Antidepressants},
  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}
}
@inproceedings{WernerMarcusSheikhbahaeietal.2018,
  author    = {Werner, Rudolf A. and Marcus, Charles and Sheikhbahaei, Sara and Higuchi, Takahiro and Solnes, Lilja B. and Rowe, Steven P. and Buck, Andreas K. and Lapa, Constantin and Javadi, Mehrbod S.},
  title     = {Diagnostic Accuracy of Visual Assessment of an Initial DaT-Scan in Comparison to a Fully Automatic Semiquantitative Method},
  series = {Journal of Nuclear Medicine},
  volume    = {59},
  booktitle = {Journal of Nuclear Medicine},
  number    = {Supplement No. 1},
  issn      = {0161-5505},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-162208},
  pages     = {626},
  year      = {2018},
  abstract  = {No abstract available.},
  subject      = {Parkinson-Krankheit},
  language  = {en}
}
@inproceedings{WernerMarcusSheikhbahaeietal.2018,
  author    = {Werner, Rudolf A. and Marcus, Charles and Sheikhbahaei, Sara and Higuchi, Takahiro and Solnes, Lilja B. and Rowe, Steven P. and Buck, Andreas K. and Lapa, Constantin and Javadi, Mehrbod S.},
  title     = {The Impact of Ageing on Dopamine Transporter Imaging},
  series = {Journal of Nuclear Medicine},
  volume    = {59},
  booktitle = {Journal of Nuclear Medicine},
  number    = {Supplement No 1},
  issn      = {0161-5505},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-162213},
  pages     = {1646},
  year      = {2018},
  abstract  = {No abstract available.},
  subject      = {Parkinson-Krankheit},
  language  = {en}
}
@inproceedings{WernerChenHiranoetal.2018,
  author    = {Werner, Rudolf A. and Chen, Xinyu and Hirano, Mitsuru and Nose, Naoko and Lapa, Constantin and Javadi, Mehrbod S. and Higuchi, Takahiro},
  title     = {The Impact of Ageing on [\(^{11}\)C]meta-Hydroxyephedrine Uptake in the Rat Heart},
  series = {Journal of Nuclear Medicine},
  volume    = {59},
  booktitle = {Journal of Nuclear Medicine},
  number    = {Supplement No 1},
  issn      = {0161-5505},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-162228},
  pages     = {100},
  year      = {2018},
  abstract  = {No abstract available.},
  subject      = {Positronen-Emissions-Tomografie},
  language  = {en}
}
@article{LapaAriasLozaHayakawaetal.2017,
  author    = {Lapa, Constantin and Arias-Loza, Paula and Hayakawa, Nobuyuki and Wakabayashi, Hiroshi and Werner, Rudolf A. and Chen, Xinyu and Shinaji, Tetsuya and Herrmann, Ken and Pelzer, Theo and Higuchi, Takahiro},
  title     = {Whitening and impaired glucose utilization of brown adipose tissue in a rat model of type 2 diabetes mellitus},
  series = {Scientific Reports},
  volume    = {7},
  journal   = {Scientific Reports},
  doi       = {10.1038/s41598-017-17148-w},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-159066},
  pages     = {16795},
  year      = {2017},
  abstract  = {Brown adipose tissue (BAT) is an attractive therapeutic target to combat diabetes and obesity due to its ability to increase glucose expenditure. In a genetic rat model (ZDF fa/fa) of type-2 diabetes and obesity, we aimed to investigate glucose utilization of BAT by \(^{18}\)F-FDG PET imaging. Male Zucker diabetic fatty (ZDF) and Male Zucker lean (ZL) control rats were studied at 13 weeks. Three weeks prior to imaging, ZDF rats were randomized into a no-restriction (ZDF-ND) and a mild calorie restriction (ZDF-CR) group. Dynamic \(^{18}\)F-FDG PET using a dedicated small animal PET system was performed under hyperinsulinemic-euglycemic clamp. \(^{18}\)F-FDG PET identified intense inter-scapular BAT glucose uptake in all ZL control rats, while no focally increased \(^{18}\)F-FDG uptake was detected in all ZDF-ND rats. Mild but significant improved BAT tracer uptake was identified after calorie restriction in diabetic rats (ZDF-CR). The weight of BAT tissue and fat deposits were significantly increased in ZDF-CR and ZDF-ND rats as compared to ZL controls, while UCP-1 and mitochondrial concentrations were significantly decreased. Whitening and severely impaired insulin-stimulated glucose uptake in BAT was confirmed in a rat model of type-2 diabetes. Additionally, calorie restriction partially restored the impaired BAT glucose uptake.},
  language  = {en}
}
@unpublished{WernerIlhanLehneretal.2018,
  author    = {Werner, Rudolf A. and Ilhan, Harun and Lehner, Sebastian and Papp, L{\´a}szl{\´o} and Zs{\´o}t{\´e}r, Norbert and Schatka, Imke and Muegge, Dirk O. and Javadi, Mehrbod S. and Higuchi, Takahiro and Buck, Andreas K. and Bartenstein, Peter and Bengel, Frank and Essler, Markus and Lapa, Constantin and Bundschuh, Ralph A.},
  title     = {Pre-therapy Somatostatin-Receptor-Based Heterogeneity Predicts Overall Survival in Pancreatic Neuroendocrine Tumor Patients Undergoing Peptide Receptor Radionuclide Therapy},
  series = {Molecular Imaging and Biology},
  journal   = {Molecular Imaging and Biology},
  issn      = {1536-1632},
  doi       = {https://doi.org/10.1007/s11307-018-1252-5},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-164624},
  year      = {2018},
  abstract  = {Purpose: Early identification of aggressive disease could improve decision-support in pancreatic neuroendocrine tumor (pNET) patients prior to peptide receptor radionuclide therapy (PRRT). The prognostic value of intratumoral textural features (TF) determined by baseline somatostatin receptor (SSTR)-PET before PRRT was analyzed. Procedures: 31 patients with G1/G2 pNET were enrolled (G2, n=23/31). Prior to PRRT with [\(^{177}\)Lu]DOTATATE (mean, 3.6 cycles), baseline SSTR-PET/CT was performed. By segmentation of 162 (median per patient, 5) metastases, intratumoral TF were computed. The impact of conventional PET parameters (SUV\(_{mean/max}\)), imaging-based TF as well as clinical parameters (Ki67, CgA) for prediction of both progression-free (PFS) and overall survival (OS) after PRRT was evaluated. Results: Within a median follow-up of 3.7y, tumor progression was detected in 21 patients (median, 1.5y) and 13/31 deceased (median, 1.9y). In ROC analysis, the TF Entropy, reflecting derangement on a voxel-by-voxel level, demonstrated predictive capability for OS (cutoff=6.7, AUC=0.71, p=0.02). Of note, increasing Entropy could predict a longer survival (>6.7, OS=2.5y, 17/31), whereas less voxel-based derangement portended inferior outcome (<6.7, OS=1.9y, 14/31). These findings were supported in a G2 subanalysis (>6.9, OS=2.8y, 9/23 vs. <6.9, OS=1.9y, 14/23). Kaplan-Meier analysis revealed a significant distinction between high- and low-risk groups using Entropy (n=31, p<0.05). For those patients below the ROC-derived threshold, the relative risk of death after PRRT was 2.73 (n=31, p=0.04). Ki67 was negatively associated with PFS (p=0.002); however, SUVmean/max failed in prognostication (n.s.). Conclusions: In contrast to conventional PET parameters, assessment of intratumoral heterogeneity demonstrated superior prognostic performance in pNET patients undergoing PRRT. This novel PET-based strategy of outcome prediction prior to PRRT might be useful for patient risk stratification.},
  subject      = {Positronen-Emissions-Tomografie},
  language  = {en}
}
@inproceedings{WernerKobayashiWakabayashietal.2017,
  author    = {Werner, Rudolf and Kobayashi, Ryohei and Wakabayashi, Hiroshi and Lapa, Constantin and Menke, Andreas and Higuchi, Takahiro},
  title     = {Effect of Antidepressants on Radiolabeled Metaiodobenzylguanidine (MIBG) Uptake},
  series = {European Heart Journal - Cardiovascular Imaging},
  volume    = {18},
  booktitle = {European Heart Journal - Cardiovascular Imaging},
  number    = {Supplement},
  publisher = {Oxford University Press},
  issn      = {2047-2404},
  doi       = {10.1093/ehjci/jex080},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-161116},
  pages     = {i52-53},
  year      = {2017},
  abstract  = {No abstract available.},
  subject      = {MIBG},
  language  = {en}
}
@inproceedings{WernerChenLapaetal.2017,
  author    = {Werner, Rudolf and Chen, Xinyu and Lapa, Constantin and Robinson, Simon and Higuchi, Takahiro},
  title     = {Intracellular behavior of the novel sympathetic nerve agent \(^{18}\)F-LMI1195},
  series = {Journal of Nuclear Cardiology},
  volume    = {24},
  booktitle = {Journal of Nuclear Cardiology},
  number    = {4 Supplement (2017) Aug},
  issn      = {1071-3581},
  doi       = {10.1007/s12350-017-0984-y},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-161137},
  pages     = {1461-1496},
  year      = {2017},
  abstract  = {No abstract available.},
  subject      = {Herz},
  language  = {en}
}
@inproceedings{WernerHiguchiMueggeetal.2017,
  author    = {Werner, Rudolf and Higuchi, Takahiro and Muegge, Dirk and Javadi, Mehrbod S. and M{\"a}rkl, Bruno and Aulmann, Christoph and Buck, Andreas K. and Fassnacht, Martin and Lapa, Constantin and Kreissl, Michael C.},
  title     = {Predictive value of FDG-PET in patients with advanced medullary thyroid cancer undergoing vandetanib treatment},
  series = {Journal of Nuclear Medicine},
  volume    = {58},
  booktitle = {Journal of Nuclear Medicine},
  number    = {no. supplement 1},
  issn      = {0161-5505},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-161147},
  pages     = {169},
  year      = {2017},
  abstract  = {Introduction: The prognosis of medullary thyroid carcinoma (MTC) is poor using common chemotherapeutic approaches. However, during the last years encouraging results of recently introduced tyrosine kinase inhibitors (TKI) such as vandetanib have been published. In this study we aimed to correlate the results of \(^{18}\)F-fluorodeoxyglucose ([\(^{18}\)F]FDG) positron emission tomography (PET) imaging with treatment outcome. Methods: Eighteen patients after thyroidectomy with recurrent/advanced MTC lesions receiving vandetanib (300 mg orally/day) could be analysed. A baseline \(^{18}\)F-FDG PET prior to and a follow-up \(^{18}\)F-FDG PET 3 months after TKI initiation were performed. During follow-up, tumor progression was assessed every 3 months including computed tomography according to RECIST. Progression-free survival (PFS) was correlated with the maximum standardized uptake value of \(^{18}\)F-FDG in lymph nodes (SUV(LN)max) or visceral metastases (SUV(MTS)max) as well as with clinical parameters using ROC analysis. Results: Within median 3.6 years of follow-up, 9 patients showed disease progression at median 8.5 months after TKI initiation. An elevated glucose consumption assessed by baseline \(^{18}\)F-FDG PET (SUV(LN)max > 7.25) could predict a shorter PFS (2 y) with an accuracy of 76.5\% (SUV(LN)max <7.25, 4.3 y; p=0.03). Accordingly, preserved tumor metabolism in the follow-up PET (SUV(MTS)max >2.7) also demonstrated an unfavorable prognosis (accuracy, 85.7\%). On the other hand, none of the clinical parameters reached significance in response prediction. Conclusions: In patients with advanced and progressive MTC, tumors with higher metabolic activity at baseline are more aggressive and more prone to progression as reflected by a shorter PFS; they should be monitored more closely. Preserved glucose consumption 3 months after treatment initiation was also related to poorer prognosis.},
  language  = {en}
}
@inproceedings{WernerLapaBucketal.2017,
  author    = {Werner, Rudolf and Lapa, Constantin and Buck, Andreas and Lassmann, Michael and H{\"a}nscheid, Heribert},
  title     = {Less is sometimes more - Accurate Dose Mapping after Endoradiotherapy with \(^{177}\)Lu-DOTATATE/-TOC by One-Single Measurement after 96 h},
  series = {Journal of Nuclear Medicine},
  volume    = {58},
  booktitle = {Journal of Nuclear Medicine},
  number    = {No. Supplement 1},
  publisher = {Society of Nuclear Medicine and Molecular Imaging},
  issn      = {0161-5505},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-161168},
  pages     = {247},
  year      = {2017},
  abstract  = {No abstract available.},
  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{LueckerathLapaAlbertetal.2015,
  author    = {L{\"u}ckerath, Katharina and Lapa, Constantin and Albert, Christa and Herrmann, Ken and J{\"o}rg, Gerhard and Samnick, Samuel and Einsele, Herrmann and Knop, Stefan and Buck, Andreas K.},
  title     = {\(^{11}\)C-Methionine-PET: a novel and sensitive tool for monitoring of early response to treatment in multiple myeloma},
  series = {Oncotarget},
  volume    = {6},
  journal   = {Oncotarget},
  number    = {10},
  doi       = {10.18632/oncotarget.3053},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-148688},
  pages     = {8418-8429},
  year      = {2015},
  abstract  = {Multiple myeloma (MM) remains an essentially incurable hematologic malignancy. However, new treatment modalities and novel drugs have been introduced and thus additional tools for therapy monitoring are increasingly needed. Therefore, we evaluated the radiotracers \(^{11}\)C-Methionine (paraprotein-biosynthesis) and \(^{18}\)F-FDG (glucose-utilization) for monitoring response to anti-myeloma-therapy and outcome prediction. Influence of proteasome-inhibition on radiotracer-uptake of different MM cell-lines and patient-derived CD138\(^{+}\) plasma cells was analyzed and related to tumor-biology. Mice xenotransplanted with MM. 1S tumors underwent MET- and FDG-\(\mu\)PET. Tumor-to-background ratios before and after 24 h, 8 and 15 days treatment with bortezomib were correlated to survival. Treatment reduced both MET and FDG uptake; changes in tracer-retention correlated with a switch from high to low CD138-expression. In xenotransplanted mice, MET-uptake significantly decreased by 30-79\% as early as 24 h after bortezomib injection. No significant differences were detected thus early with FDG. This finding was confirmed in patient-derived MM cells. Importantly, early reduction of MET-but not FDG-uptake correlated with improved survival and reduced tumor burden in mice. Our results suggest that MET is superior to FDG in very early assessment of response to anti-myeloma-therapy. Early changes in MET-uptake have predictive potential regarding response and survival. MET-PET holds promise to individualize therapies in MM in future.},
  language  = {en}
}
@unpublished{WernerBundschuhBundschuhetal.2018,
  author    = {Werner, Rudolf A. and Bundschuh, Ralph A. and Bundschuh, Lena and Javadi, Mehrbod S. and Leal, Jeffrey P. and Higuchi, Takahiro and Pienta, Kenneth J. and Buck, Andreas K. and Pomper, Martin G. and Gorin, Michael A. and Lapa, Constantin and Rowe, Steven P.},
  title     = {Interobserver Agreement for the Standardized Reporting System PSMA-RADS 1.0 on \(^{18}\)F-DCFPyL PET/CT Imaging},
  series = {Journal of Nuclear Medicine},
  journal   = {Journal of Nuclear Medicine},
  issn      = {0161-5505},
  doi       = {10.2967/jnumed.118.217588},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-167788},
  year      = {2018},
  abstract  = {Objectives: Recently, the standardized reporting and data system for prostate-specific membrane antigen (PSMA)-targeted positron emission tomography (PET) imaging studies, termed PSMA-RADS version 1.0, was introduced. We aimed to determine the interobserver agreement for applying PSMA-RADS to imaging interpretation of 18F-DCFPyL PET examinations in a prospective setting mimicking the typical clinical work-flow at a prostate cancer referral center. Methods: Four readers (two experienced readers (ER, > 3 years of PSMA-targeted PET interpretation experience) and two inexperienced readers (IR, < 1 year of experience)), who had all read the initial publication on PSMA-RADS 1.0, assessed 50 18F-DCFPyL PET/computed tomography (CT) studies independently. Per scan, a maximum of 5 target lesions were selected by the observers and a PSMA-RADS score for every target lesion was recorded. No specific pre-existing conditions were placed on the selection of the target lesions, although PSMA-RADS 1.0 suggests that readers focus on the most highly avid or largest lesions. An overall scan impression based on PSMA-RADS was indicated and interobserver agreement rates on a target lesion-based, on an organ-based, and on an overall PSMA-RADS score-based level were computed. Results: The number of target lesions identified by each observer were as follows: ER 1, 123; ER 2, 134; IR 1, 123; and IR 2, 120. Among those selected target lesions, 125 were chosen by at least two individual observers (all four readers selected the same target lesion in 58/125 (46.4\%) instances, three readers in 40/125 (32\%) and two observers in 27/125 (21.6\%) instances). The interobserver agreement for PSMA-RADS scoring among identical target lesions was good (intraclass correlation coefficient (ICC) for four, three and two identical target lesions, ≥0.60, respectively). For lymph nodes, an excellent interobserver agreement was derived (ICC=0.79). The interobserver agreement for an overall scan impression based on PSMA-RADS was also excellent (ICC=0.84), with a significant difference for ER (ICC=0.97) vs. IR (ICC=0.74, P=0.005). Conclusions: PSMA-RADS demonstrates a high concordance rate in this study, even among readers with different levels of experience. This suggests that PSMA-RADS can be effectively used for communication with clinicians and can be implemented in the collection of data for large prospective trials.},
  subject      = {Positronen-Emissions-Tomografie},
  language  = {en}
}
@unpublished{YinWernerHiguchietal.2018,
  author    = {Yin, Yafu and Werner, Rudolf A. and Higuchi, Takahiro and Lapa, Constantin and Pienta, Kenneth J. and Pomper, Martin G. and Gorin, Michael A. and Rowe, Steven P.},
  title     = {Follow-Up of Lesions with Equivocal Radiotracer Uptake on PSMA-Targeted PET in Patients with Prostate Cancer: Predictive Values of the PSMA-RADS-3A and PSMARADS- 3B Categories},
  series = {Journal of Nuclear Medicine},
  journal   = {Journal of Nuclear Medicine},
  issn      = {0161-5505},
  doi       = {10.2967/jnumed.118.217653},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-167594},
  year      = {2018},
  abstract  = {Purpose: Prostate-specific membrane antigen (PSMA)-targeted positron emission tomography (PET) imaging has become commonly utilized in patients with prostate cancer (PCa). The PSMA reporting and data system version 1.0 (PSMA-RADS version 1.0) categorizes lesions on the basis of the likelihood of PCa involvement, with PSMA-RADS-3A (soft tissue) and PSMA-RADS-3B (bone) lesions being indeterminate for the presence of disease. We retrospectively reviewed the imaging follow-up of such lesions to determine the rate at which they underwent changes suggestive of underlying PCa. Methods: PET/CT imaging with \(^{18}\)F-DCFPyL was carried out in 110 patients with PCa and lesions were categorized according to PSMA-RADS Version 1.0. 56/110 (50.9\%) patients were determined to have indeterminate PSMA-RADS-3A or PSMA-RADS-3B lesions and 22/56 (39.3\%) patients had adequate follow-up to be included in the analysis. The maximum standardized uptake values (SUV\(_{max}\)) of the lesions were obtained and the ratios of SUV\(_{max}\) of the lesions to SUV\(_{mean}\) of blood pool (SUV\(_{max}\)-lesion/SUV\(_{mean}\)-bloodpool) were calculated. Pre-determined criteria were used to evaluate the PSMA-RADS-3A and PSMA-RADS-3B lesions on follow-up imaging to determine if they demonstrated evidence of underlying malignancy. Results: A total of 46 lesions in 22 patients were considered indeterminate for PCa (i.e. PSMA-RADS-3A (32 lesions) or PSMA-RADS-3B (14 lesions)) and were evaluable on follow-up imaging. 27/46 (58.7\%) lesions demonstrated changes on follow-up imaging consistent with the presence of underlying PCa at baseline. These lesions included 24/32 (75.0\%) PSMA-RADS-3A lesions and 3/14 (21.4\%) lesions categorized as PSMA-RADS-3B. The ranges of SUVmax and SUVmax-lesion/SUVmean-bloodpool overlapped between those lesions demonstrating changes consistent with malignancy on follow-up imaging and those lesions that remained unchanged on follow-up. Conclusion: PSMA-RADS-3A and PSMA-RADS-3B lesions are truly indeterminate in that proportions of findings in both categories demonstrate evidence of malignancy on follow-up imaging. Overall, PSMA-RADS-3A lesions are more likely than PSMA-RADS-3B lesions to represent sites of PCa and this information should be taken into when guiding patient therapy.},
  subject      = {Positronen-Emissions-Tomografie},
  language  = {en}
}
@article{LapaKircherSchirbeletal.2017,
  author    = {Lapa, Constantin and Kircher, Stefan and Schirbel, Andreas and Rosenwald, Andreas and Kropf, Saskia and Pelzer, Theo and Walles, Thorsten and Buck, Andreas K. and Weber, Wolfgang A. and Wester, Hans-Juergen and Herrmann, Ken and L{\"u}ckerath, Katharina},
  title     = {Targeting CXCR4 with [\(^{68}\)Ga]Pentixafor: a suitable theranostic approach in pleural mesothelioma?},
  series = {Oncotarget},
  volume    = {8},
  journal   = {Oncotarget},
  number    = {57},
  doi       = {10.18632/oncotarget.18235},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-169989},
  pages     = {96732-96737},
  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. This study investigated the feasibility of CXCR4-directed imaging with positron emission tomography/computed tomography (PET/CT) using [\(^{68}\)Ga]Pentixafor in malignant pleural mesothelioma. Six patients with pleural mesothelioma underwent [\(^{68}\)Ga]Pentixafor-PET/CT. 2′-[\(^{18}\)F]fluoro-2′-deoxy-D-glucose ([\(^{18}\)F]FDG)-PET/CT (4/6 patients) and immunohistochemistry obtained from biopsy or surgery (all) served as standards of reference. Additionally, 9 surgical mesothelioma samples were available for histological work-up. Whereas [\(^{18}\)F]FDG-PET depicted active lesions in all patients, [\(^{68}\)Ga]Pentixafor-PET/CT recorded physiologic tracer distribution and none of the 6 patients presented [\(^{68}\)Ga]Pentixafor-positive lesions. This finding paralleled results of immunohistochemistry which also could not identify relevant CXCR4 surface expression in the samples analyzed. In contrast to past reports, our data suggest widely absence of CXCR4 expression in pleural mesothelioma. Hence, robust cell surface expression should be confirmed prior to targeting this chemokine receptor for diagnosis and/or therapy.},
  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}
}