@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} } @article{BeykanDamEberleinetal.2016, author = {Beykan, Seval and Dam, Jan S. and Eberlein, Uta and Kaufmann, Jens and Kj{\ae}rgaard, Benedict and J{\o}dal, Lars and Bouterfa, Hakim and Bejot, Romain and Lassmann, Michael and Jensen, Svend Borup}, title = {\(^{177}\)Lu-OPS201 targeting somatostatin receptors: in vivo biodistribution and dosimetry in a pig model}, series = {EJNMMI Research}, volume = {6}, journal = {EJNMMI Research}, number = {50}, doi = {10.1186/s13550-016-0204-9}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-146888}, year = {2016}, abstract = {Background \(^{177}\)Lu is used in peptide receptor radionuclide therapies for the treatment of neuroendocrine tumors. Based on the recent literature, SST2 antagonists are superior to agonists in tumor uptake. The compound OPS201 is the novel somatostatin antagonist showing the highest SST2 affinity. The aim of this study was to measure the in vivo biodistribution and dosimetry of \(^{177}\)Lu-OPS201 in five anesthetized Danish Landrace pigs as an appropriate substitute for humans to quantitatively assess the absorbed doses for future clinical applications. Results \(^{177}\)Lu-OPS201 was obtained with a specific activity ranging from 10 to 17 MBq/μg. Prior to administration, the radiochemical purity was measured as s > 99.7 \% in all cases. After injection, fast clearance of the compound from the blood stream was observed. Less than 5 \% of the injected activity was presented in blood 10 min after injection. A series of SPECT/CT and whole-body scans conducted until 10 days after intravenous injection showed uptake mostly in the liver, spine, and kidneys. There was no visible uptake in the spleen. Blood samples were taken to determine the time-activity curve in the blood. Time-activity curves and time-integrated activity coefficients were calculated for the organs showing visible uptake. Based on these data, the absorbed organ dose coefficients for a 70-kg patient were calculated with OLINDA/EXM. For humans after an injection of 5 GBq \(^{177}\)Lu-OPS201, the highest predicted absorbed doses are obtained for the kidneys (13.7 Gy), the osteogenic cells (3.9 Gy), the urinary bladder wall (1.8 Gy), and the liver (1.0 Gy). No metabolites of 177Lu-OPS201 were found by radio HPLC analysis. None of the absorbed doses calculated will exceed organ toxicity levels. Conclusions The \(^{177}\)Lu-OPS201 was well tolerated and caused no abnormal physiological or behavioral signs. In vivo distributions and absorbed doses of pigs are comparable to those observed in other publications. According to the biodistribution data in pigs, presented in this work, the expected radiation exposure in humans will be within the acceptable range.}, 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{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{IsaiasSpiegelBrumbergetal.2014, author = {Isaias, Ioannis Ugo and Spiegel, J{\"o}rg and Brumberg, Joachim and Cosgrove, Kelly P. and Marotta, Giorgio and Oishi, Naoya and Higuchi, Takahiro and K{\"u}sters, Sebastian and Schiller, Markus and Dillmann, Ulrich and van Dyck, Christopher H. and Buck, Andreas and Herrmann, Ken and Schloegl, Susanne and Volkmann, Jens and Lassmann, Michael and Fassbender, Klaus and Lorenz, Reinhard and Samnick, Samuel}, title = {Nicotinic acetylcholine receptor density in cognitively intact subjects at an early stage of Parkinson's disease}, series = {Frontiers in Aging Neuroscience}, volume = {6}, journal = {Frontiers in Aging Neuroscience}, doi = {10.3389/fnagi.2014.00213}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-119351}, pages = {213}, year = {2014}, abstract = {We investigated in vivo brain nicotinic acetylcholine receptor (nAChR) distribution in cognitively intact subjects with Parkinson's disease (PD) at an early stage of the disease. Fourteen patients and 13 healthy subjects were imaged with single photon emission computed tomography and the radiotracer 5-[(123)I]iodo-3-[2(S)-2-azetidinylmethoxy]pyridine ([(123)I]5IA). Patients were selected according to several criteria, including short duration of motor signs (<7 years) and normal scores at an extensive neuropsychological evaluation. In PD patients, nAChR density was significantly higher in the putamen, the insular cortex and the supplementary motor area and lower in the caudate nucleus, the orbitofrontal cortex, and the middle temporal gyrus. Disease duration positively correlated with nAChR density in the putamen ipsilateral (ρ = 0.56, p < 0.05) but not contralateral (ρ = 0.49, p = 0.07) to the clinically most affected hemibody. We observed, for the first time in vivo, higher nAChR density in brain regions of the motor and limbic basal ganglia circuits of subjects with PD. Our findings support the notion of an up-regulated cholinergic activity at the striatal and possibly cortical level in cognitively intact PD patients at an early stage of disease.}, language = {en} } @article{EberleinBroeerVandevoordeetal.2011, author = {Eberlein, Uta and Br{\"o}er, J{\"o}rn Hendrik and Vandevoorde, Charlot and Santos, Paula and Bardi{\`e}s, Manuel and Bacher, Klaus and Nosske, Dietmar and Lassmann, Michael}, title = {Biokinetics and dosimetry of commonly used radiopharmaceuticals in diagnostic nuclear medicine - a review}, series = {European Journal of Nuclear Medicine and Molecular Imaging}, volume = {38}, journal = {European Journal of Nuclear Medicine and Molecular Imaging}, number = {12}, doi = {10.1007/s00259-011-1904-z}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-133846}, pages = {2269-2281}, year = {2011}, abstract = {Purpose The impact on patients' health of radiopharmaceuticals in nuclear medicine diagnostics has not until now been evaluated systematically in a European context. Therefore, as part of the EU-funded Project PEDDOSE.NET (www.​peddose.​net), we review and summarize the current knowledge on biokinetics and dosimetry of commonly used diagnostic radiopharmaceuticals. Methods A detailed literature search on published biokinetic and dosimetric data was performed mostly via PubMed (www.​ncbi.​nlm.​nih.​gov/​pubmed). In principle the criteria for inclusion of data followed the EANM Dosimetry Committee guidance document on good clinical reporting. Results Data on dosimetry and biokinetics can be difficult to find, are scattered in various journals and, especially in paediatric nuclear medicine, are very scarce. The data collection and calculation methods vary with respect to the time-points, bladder voiding, dose assessment after the last data point and the way the effective dose was calculated. In many studies the number of subjects included for obtaining biokinetic and dosimetry data was fewer than ten, and some of the biokinetic data were acquired more than 20 years ago. Conclusion It would be of interest to generate new data on biokinetics and dosimetry in diagnostic nuclear medicine using state-of-the-art equipment and more uniform dosimetry protocols. For easier public access to dosimetry data for diagnostic radiopharmaceuticals, a database containing these data should be created and maintained.}, language = {en} } @article{HerrmannWiederLassmannetal.2014, author = {Herrmann, Ken and Wieder, Hinrich A. and Lassmann, Michael and Allen-Auerbach, Martin S. and Czernin, Johannes}, title = {Clinical use of bone-targeting radiopharmaceuticals with focus on alpha-emitters}, doi = {10.4329/wjr.v6.i7.480}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-113014}, year = {2014}, abstract = {Various single or multi-modality therapeutic options are available to treat pain of bone metastasis in patients with prostate cancer. Different radionuclides that emit β-rays such as 153Samarium and 89Strontium and achieve palliation are commercially available. In contrast to β-emitters, 223Radium as a α-emitter has a short path-length. The advantage of the α-emitter is thus a highly localized biological effect that is caused by radiation induced DNA double-strand breaks and subsequent cell killing and/or limited effectiveness of cellular repair mechanisms. Due to the limited range of the α-particles the bone surface to red bone marrow dose ratio is also lower for 223Radium which is expressed in a lower myelotoxicity. The α emitter 223Radium dichloride is the first radiopharmaceutical that significantly prolongs life in castrate resistant prostate cancer patients with wide-spread bone metastatic disease. In a phase III, randomized, double-blind, placebo-controlled study 921 patients with castration-resistant prostate cancer and bone metastases were randomly assigned. The analysis confirmed the 223Radium survival benefit compared to the placebo (median, 14.9 mo vs 11.3 mo; P < 0.001). In addition, the treatment results in pain palliation and thus, improved quality of life and a delay of skeletal related events. At the same time the toxicity profile of 223Radium was favourable. Since May 2013, 223Radium dichloride (Xofigo®) is approved by the US Food and Drug Administration. Core tip: The incidence rate of prostate cancer worldwide is high. Ninety percent of patients dying of prostate cancer have bone metastases with varying symptoms which are significantly impairing their quality of life. 223Radium is the first therapeutic that results in a survival benefit for patients with bone metastatic, castrate resistant prostate cancer. 223Radium was also associated with low myelosuppression rates and fewer adverse events.This article provides an overview of the pre-clinical and clinical trials with 223Radium.}, language = {en} } @article{LassmannPreylowskiSchloegletal.2013, author = {Lassmann, Michael and Preylowski, Veronika and Schl{\"o}gl, Susanne and Schoenahl, Fr{\´e}d{\´e}ric and J{\"o}rg, Gerhard and Samnick, Samuel and Buck, Andreas K.}, title = {Is the Image Quality of I-124-PET Impaired by an Automatic Correction of Prompt Gammas?}, series = {PLoS ONE}, journal = {PLoS ONE}, doi = {10.1371/journal.pone.0071729}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-96863}, year = {2013}, abstract = {Objectives The aim of this study is to evaluate the quality of I-124 PET images with and without prompt gamma compensation (PGC) by comparing the recovery coefficients (RC), the signal to noise ratios (SNR) and the contrast to F-18 and Ga-68. Furthermore, the influence of the PGC on the quantification and image quality is evaluated. Methods For measuring the image quality the NEMA NU2-2001 PET/SPECT-Phantom was used containing 6 spheres with a diameter between 10 mm and 37 mm placed in water with different levels of background activity. Each sphere was filled with the same activity concentration measured by an independently cross-calibrated dose calibrator. The "hot" sources were acquired with a full 3D PET/CT (Biograph mCT®, Siemens Medical USA). Acquisition times were 2 min for F-18 and Ga-68, and 10 min for I-124. For reconstruction an OSEM algorithm was applied. For I-124 the images were reconstructed with and without PGC. For the calculation of the RCs the activity concentrations in each sphere were determined; in addition, the influence of the background correction was studied. Results The RCs of Ga-68 are the smallest (79\%). I-124 reaches similar RCs (87\% with PGC, 84\% without PGC) as F-18 (84\%). showing that the quantification of I-124 images is similar to F-18 and slightly better than Ga-68. With background activity the contrast of the I-124 PGC images is similar to Ga-68 and F-18 scans. There was lower background activity in the I-124 images without PGC, which probably originates from an overcorrection of the scatter contribution. Consequently, the contrast without PGC was much higher than with PGC. As a consequence PGC should be used for I-124. Conclusions For I-124 there is only a slight influence on the quantification depending on the use of the PGC. However, there are considerable differences with respect to I-124 image quality.}, language = {en} } @article{KreisslHaenscheidLoehretal.2012, author = {Kreissl, Michael C. and H{\"a}nscheid, Heribert and L{\"o}hr, Mario and Verburg, Frederik A. and Schiller, Markus and Lassmann, Michael and Reiners, Christoph and Samnick, Samuel S. and Buck, Andreas K. and Flentje, Michael and Sweeney, Reinhart A.}, title = {Combination of peptide receptor radionuclide therapy with fractionated external beam radiotherapy for treatment of advanced symptomatic meningioma}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-75540}, year = {2012}, abstract = {Background: External beam radiotherapy (EBRT) is the treatment of choice for irresectable meningioma. Due to the strong expression of somatostatin receptors, peptide receptor radionuclide therapy (PRRT) has been used in advanced cases. We assessed the feasibility and tolerability of a combination of both treatment modalities in advanced symptomatic meningioma. Methods: 10 patients with irresectable meningioma were treated with PRRT (177Lu-DOTA0,Tyr3 octreotate or - DOTA0,Tyr3 octreotide) followed by external beam radiotherapy (EBRT). EBRT performed after PRRT was continued over 5-6 weeks in IMRT technique (median dose: 53.0 Gy). All patients were assessed morphologically and by positron emission tomography (PET) before therapy and were restaged after 3-6 months. Side effects were evaluated according to CTCAE 4.0. Results: Median tumor dose achieved by PRRT was 7.2 Gy. During PRRT and EBRT, no side effects>CTCAE grade 2 were noted. All patients reported stabilization or improvement of tumor-associated symptoms, no morphologic tumor progression was observed in MR-imaging (median follow-up: 13.4 months). The median pre-therapeutic SUVmax in the meningiomas was 14.2 (range: 4.3-68.7). All patients with a second PET after combined PRRT + EBRT showed an increase in SUVmax (median: 37\%; range: 15\%-46\%) to a median value of 23.7 (range: 8.0-119.0; 7 patients) while PET-estimated volume generally decreased to 81 ± 21\% of the initial volume. Conclusions: The combination of PRRT and EBRT is feasible and well tolerated. This approach represents an attractive strategy for the treatment of recurring or progressive symptomatic meningioma, which should be further evaluated.}, subject = {Medizin}, language = {en} } @article{DicksonEberleinLassmann2022, author = {Dickson, John and Eberlein, Uta and Lassmann, Michael}, title = {The effect of modern PET technology and techniques on the EANM paediatric dosage card}, series = {European Journal of Nuclear Medicine and Molecular Imaging}, volume = {49}, journal = {European Journal of Nuclear Medicine and Molecular Imaging}, number = {6}, issn = {1619-7089}, doi = {10.1007/s00259-021-05635-2}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-265624}, pages = {1964-1969}, year = {2022}, abstract = {Aim Recent advancements in PET technology have brought with it significant improvements in PET performance and image quality. In particular, the extension of the axial field of view of PET systems, and the introduction of semiconductor technology into the PET detector, initially for PET/MR, and more recently available long-field-of-view PET/CT systems (≥ 25 cm) have brought a step change improvement in the sensitivity of PET scanners. Given the requirement to limit paediatric doses, this increase in sensitivity is extremely welcome for the imaging of children and young people. This is even more relevant with PET/MR, where the lack of CT exposures brings further dose reduction benefits to this population. In this short article, we give some details around the benefits around new PET technology including PET/MR and its implications on the EANM paediatric dosage card. Material and methods Reflecting on EANM adult guidance on injected activities, and making reference to bed overlap and the concept of MBq.min bed\(^{-1}\) kg\(^{-1}\), we use published data on image quality from PET/MR systems to update the paediatric dosage card for PET/MR and extended axial field of view (≥ 25 cm) PET/CT systems. However, this communication does not cover the expansion of paediatric dosing for the half-body and total-body scanners that have recently come to market. Results In analogy to the existing EANM dosage card, new parameters for the EANM paediatric dosage card were developed (class B, baseline value: 10.7 MBq, minimum recommended activity 10 MBq). The recommended administered activities for the systems considered in this communication range from 11 MBq [\(^{18}\)F]FDG for a child with a weight of 3 kg to 149 MBq [\(^{18}\)F]FDG for a paediatric patient weight of 68 kg, assuming a scan of 3 min per bed position. The mean effective dose over all ages (1 year and older) is 2.85 mSv. Conclusion With this, recommendations for paediatric dosing are given for systems that have not been considered previously.}, language = {en} }