TY - THES A1 - Hartrampf, Philipp Emanuel T1 - Evaluation der PET-Tracer [\(^1\)\(^8\)F]FDG, [\(^1\)\(^8\)F]Cholin und [\(^6\)\(^8\)Ga]PSMA I&T zur nicht-invasiven Charakterisierung von Prostatakarzinomzellen und des Ansprechens auf eine Docetaxeltherapie T1 - Evaluation of PET tracers [\(^1\)\(^8\)F]FDG, [\(^1\)\(^8\)F]choline and [\(^6\)\(^8\)Ga]PSMA I&T for non-invasive characterization of prostate cancer cells and response to docetaxel therapy N2 - Das Prostatakarzinom (PCa) stellt derzeit in Deutschland die häufigste Krebserkrankung der männlichen Bevölkerung dar und steht bei den tödlich verlaufenden Malignomen an zweiter Stelle. Aktuell umfasst die Diagnostik immer öfter auch eine molekulare Bildgebung mittels PET/CT und den Tracern [18F]Cholin und [68Ga]PSMA. Letzterer detektiert selektiv das prostataspezifische Membranantigen (PSMA), welches in Prostatakarzinomzellen häufig überexprimiert ist. Das Wachstum von PCa geschieht in der Regel androgenabhängig, wobei sich auch teilweise eine androgenunabhängige Entwicklung findet. Für das bei kastrationsresistenten Karzinomen und fortgeschrittenen Stadien eingesetzte Chemotherapeutikum Docetaxel, werden immer wieder Resistenzentwicklungen beobachtet, wodurch dieses nur unzureichend effektiv ist. Ziel dieser Arbeit war es, die Eignung verschiedener PET-Tracer ([18F]FDG, [18F]Cholin und [68Ga]PSMA) zur Bildgebung androgenabhängiger und -unabhängiger Prostatakarzinomzellen zu testen sowie ihr Potential zur Beurteilung des Therapieansprechens auf Docetaxel zu untersuchen. Weiterhin sollte untersucht werden, ob die [68Ga]PSMA-Retention mit der PSMA-Expression korreliert. Im zweiten Teil wurde ein Zusammenhang zwischen der Expression von PSMA und der Resistenzentwicklung gegen Docetaxel untersucht. Methoden: Für die in-vitro Experimente wurden die hormonabhängige Zelllinie LNCaP sowie die hormonunabhängige Zelllinie LNCaP C4-2 verwendet. Im zweiten Teil wurden zusätzlich PSMA-negative PC-3 Zellen eingesetzt. Die aufgenommene bzw. gebundene Traceraktivität wurde mittels Gammacounter gemessen. Die Untersuchung der PSMA-Expression erfolgte mit Western-Blot und Durchflusszytometrie. Ein PSMA-Knockdown-System wurde mittels siRNA in LNCaP-Zellen etabliert. Ergebnisse: Die PSMA-Expression und die Sensitivität gegenüber Docetaxel waren bei LNCaP Zellen tendenziell erhöht gegenüber der LNCaP C4-2 Zelllinie. Nach Docetaxelbehandlung zeigte sich in beiden Zellreihen eine unveränderte PSMA-Expression. Der PSMA-spezifische PET-Tracer zeigte, im Vergleich zu den metabolischen Tracern [18F]FDG und [18F]Cholin, eine nur sehr geringe Retention. Im Vergleich der Zelllinien untereinander nahmen LNCaP C4-2 Zellen ca. 50 % mehr [18F]FDG auf als LNCaP Zellen. Die Aufnahme von [18F]Cholin unterschied sich nicht signifikant. Der Tracer [68Ga]PSMA zeigte eine höhere Bindung an LNCaP Zellen im Vergleich zu LNCaP C4-2 Zellen. In weiteren Versuchen konnte gezeigt werden, dass sowohl [18F]FDG als auch [18F]Cholin, nicht jedoch [68Ga]PSMA in vitro ein Therapieansprechen auf Docetaxel durch verminderte Traceraufnahme in beiden Zelllinien aufzeigen. Es konnte zudem eine direkte Korrelation zwischen der [68Ga]PSMA-Bindung und der PSMA-Expression nachgewiesen werden. Nach einer siRNA-vermittelten Verminderung der PSMA-Expression in LNCaP Zellen (Knockdown-Zellen) zeigte sich eine deutlich geringere Sensitivität für Docetaxel. Gleichzeitig war jedoch die Docetaxelsensitivität von PSMA-negativen PC-3 Zellen höher als die von LNCaP Knockdown-Zellen. Schlussfolgerung: Insgesamt zeigten unsere Untersuchungen, dass sich die PET-Tracer [18F]FDG und [68Ga]PSMA zur Unterscheidung des androgenabhängigen Zellmodells vom androgenunabhängigen Modell eignen. Außerdem ermöglicht der [68Ga]PSMA-Tracer eine Einschätzung der PSMA-Expression. Die Tracer [18F]FDG und [18F]Cholin eignen sich in vitro für die Beurteilung des Therapieansprechens einer Docetaxeltherapie, [68Ga]PSMA dagegen nicht. Die PSMA-Expression scheint ein entscheidender, aber nicht alleinstehender Faktor für die Sensitivität von LNCaP Zellen gegenüber Docetaxel zu sein. Es scheinen hierbei allerdings eher der Verlust von PSMA, wie im Knockdown-Modell induziert, sowie bislang unbekannte Faktoren eine wichtige Rolle zu spielen. N2 - Prostate carcinoma (PCa) is currently the most frequent cancer in men in Germany and is the second leading cause of cancer deaths. Currently, diagnostics more and more often include molecular imaging using PET/CT and the tracers [18F]choline and [68Ga]PSMA. The latter selectively detects the prostate-specific membrane antigen (PSMA), which is often overexpressed in prostate cancer cells. The growth of PCa is usually androgen-dependent, although it is sometimes also developing independently of androgen. For the chemotherapeutic agent docetaxel, which is used for castration-resistant carcinomas and advanced stages, the development of resistance is observed again and again, resulting in insufficient efficacy. The aim of this work was to evaluate the potential of different PET tracers ([18F]FDG, [18F]Choline and [68Ga]PSMA) for the imaging of androgen-dependent and independent prostate carcinoma cells as well as their potential for the assessment of therapy response to docetaxel. Furthermore, it should be investigated whether [68Ga]PSMA uptake correlates with PSMA expression. In the second part, an association between the expression of PSMA and the development of resistance to docetaxel was investigated. Methods: For the in vitro experiments the hormone-dependent cell line LNCaP and the hormone-independent cell line LNCaP C4-2 were used. In the second part PSMA-negative PC-3 cells were additionally used. The tracer uptake and binding activity was measured by gamma counter. PSMA expression was determined by Western blot and flow cytometry. A PSMA knockdown system was established in LNCaP cells using siRNA. Results: PSMA expression and sensitivity to docetaxel were increased in LNCaP cells compared to the LNCaP C4-2 cells. After docetaxel treatment, both cell lines showed unchanged PSMA expression. Compared to the metabolic tracers [18F]FDG and [18F]choline, the PSMA-specific PET tracer showed very low uptake. In comparison of the cell lines, LNCaP C4-2 cells took up about 50 % more [18F]FDG than LNCaP cells. The uptake of [18F]choline did not differ significantly. The tracer [68Ga]PSMA showed a higher binding to LNCaP cells compared to LNCaP C4-2 cells. In further experiments it was observed that both [18F]FDG and [18F]choline, but not [68Ga]PSMA, in vitro showed a therapy response to docetaxel by reduced tracer uptake in both cell lines. A direct correlation between [68Ga]PSMA binding and PSMA expression was also found. After a siRNA-mediated reduction of PSMA expression in LNCaP cells (knockdown cells), a significantly lower sensitivity for docetaxel was observed. At the same time, however, the docetaxel sensitivity of PSMA-negative PC-3 cells was higher than that of LNCaP knockdown cells. Conclusion: Overall, our investigations showed that the PET tracers [18F]FDG and [68Ga]PSMA are suitable for differentiating the androgen-dependent cell model from the androgen-independent model. In addition, the [68Ga]PSMA tracer allows an assessment of PSMA expression. The tracers [18F]FDG and [18F]choline are suitable for in vitro assessment of response to docetaxel therapy, whereas [68Ga]PSMA is not. PSMA expression seems to be a critical, but not unique, factor for the sensitivity of LNCaP cells to docetaxel. However, the loss of PSMA, as induced in the knockdown model, as well as unknown factors seem to play an important role. KW - Positronen-Emissions-Tomografie KW - PSMA KW - [18]F-Cholin KW - [68]Ga-PSMA I&T KW - Docetaxel KW - LNCaP KW - [18]F-choline Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-176299 ER - TY - THES A1 - Heckl, Steffen T1 - Kohlenhydratmalassimilation bei der Hashimotothyreoiditis T1 - Evidence of impaired carbohydrate assimilation in euthyroid patients with Hashimoto's thyroiditis N2 - Die autoimmune Thyreoiditis nach Hashimoto stellt aktuell eine der häufigsten Autoimmunerkrankungen eines Organs und die häufigste Ursache der Hypothyreose dar. Die Hashimotothyreoiditis (HT) weist eine hohe Prävalenz und Inzidenz auf. Es existieren Hinweise, dass die Inzidenz der HT aus noch nicht geklärten Gründen gestiegen sein könnte. Die Kohlenhydrate Fruktose, Laktose und Sorbitol werden in der Lebensmittelproduktion umfassend eingesetzt. Insbesondere die industrielle Verwendung sowie der weltweite Konsum von Fruktose und Laktose unterlagen in den letzten Jahrzehnten einer rasanten Steigerung, obwohl ein hoher Prozentsatz der Bevölkerung zur Malassimilation jener Kohlenhydrate prädisponiert ist. In einer internistischen Praxis (Praxis Frau Dr. med. I. Heckl, Bad Homburg) zeigte sich, dass HT-Patienten trotz verifizierter Euthyreose vermehrt über gastrointestinale Symptome berichteten. Unter anderem wurden eine bakterielle Fehlbesiedelung des Dünndarmes und eine Zöliakie ausgeschlossen. In der weiteren Abklärung durch die Praxis Dr. I. Heckl wurde eine deutliche Häufung der Malassimilation der Kohlenhydrate Fruktose, Laktose oder Sorbitol unter euthyreoten HT-Patienten ersichtlich. In Abhängigkeit von einer konsequenten Nahrungsumstellung normalisierten sich regelmäßig das Befinden der Patienten sowie die sonographischen, die serologischen und die laborchemischen Marker der HT, sodass man einen ursächlichen Zusammenhang empirisch vermuten konnte. Im Rahmen einer prospektiven Studie sollte dieser neu beobachtete Zusammenhang zwischen der HT und der Kohlenhydratmalassimilation in der Klinik und Poliklinik für Nuklearmedizin der Universität Würzburg untersucht werden. In einem unizentrischen Fall-Kontroll-Studiendesign wurden 45 euthyreote HT-Patienten und 38 schilddrüsengesunde Kontrollpersonen auf das Vorliegen einer Kohlenhydratmalassimilation mittels des Wasserstoffatemtests (H2-Atemtest) untersucht. Alle Probanden erhielten einen Fruktose-H2-Atemtest sowie einen Laktose-H2-Atemtest inklusive einer kapillären Blutglukosemessung. Im Falle eines positiven Ergebnisses des Fruktose-H2-Atemtests wurde ein Glukose-H2-Atemtest zum Ausschluss einer bakteriellen Fehlbesiedelung des Dünndarmes durchgeführt. Lieferte der Fruktose-H2-Atemtest ein negatives Ergebnis, so folgte ein H2-Atemtest mit Sorbitol. Das Auftreten gastrointestinaler Symptome während der Testdurchführung wurde dokumentiert. Symptomfragebögen und semiquantitative Ernährungsfragebögen im retrospektiven Design dienten der Erfassung alltäglicher Symptome und Ernährungsgewohnheiten. Blutproben dienten der Messung von Schilddrüsenhormonen, Schilddrüsenautoantikörpern, Gewebstransglutaminase-Antikörpern und Antiparietalzell-Autoantikörpern. Unter den euthyreoten HT-Patienten konnte ein signifikant häufigeres Auftreten der Fruktose- sowie der Laktosemalassimilation im Vergleich zu den schilddrüsengesunden Kontrollpersonen demonstriert werden. Die Fruktosemalassimilation wurde bei den HT-Patienten mit 48,9% signifikant häufiger als in der Kontrollgruppe nachgewiesen (p=0,035). Im Kontrollgruppenkollektiv hatte eine Fruktosemalassimilation lediglich bei 26,3% der Probanden bestanden. Eine Laktosemalassimilation wurde bei den HT-Patienten mit 42,2% signifikant häufiger als im Kontrollkollektiv diagnostiziert, welches in 21,1% der Fälle eine Laktosemalassimilation aufwies (p=0,04). Insgesamt lag eine Fruktose- und / oder Laktosemalassimilation bei 73,3% der HT-Patienten und bei 42,1% der Kontrollgruppenprobanden vor. Somit vertrugen nur 26,7% der Fallgruppe, jedoch 57,9% der Kontrollgruppe beide Kohlenhydrate (p=0,004). Hinsichtlich der Prävalenz der Sorbitolmalassimilation oder eines positiven Glukose-H2-Atemtestes kam kein signifikanter Unterschied zur Darstellung. Die Auswertung der Ernährungsfragebögen zeigte für beide Kollektive eine vergleichbare durchschnittliche Konsummenge der jeweiligen Kohlenhydrate auf. Gastrointestinale Symptome waren während des Laktose-H2-Atemtests sowie während des Fruktose-H2-Atemtests jeweils in der Fallgruppe signifikant häufiger anzutreffen als in der Kontrollgruppe. Auch im Hinblick auf das Alltagsleben beschrieben die euthyreoten HT-Patienten signifikant häufiger unter den folgenden Symptomen zu leiden: Weicher Stuhlgang, Oberbauchschmerzen, Meteorismus, laute Darmgeräusche, „Kugelbauch“, Sodbrennen, Schleimauflagerungen des Stuhlgangs, Obstipation, Müdigkeit, postprandiale Kraftlosigkeit, Depressionen, Heißhunger auf Süßes, Migräne, Konzentrationsmangel und eine vermehrte Infektanfälligkeit. Zur Kausalität des hier erstmals beschriebenen Zusammenhangs existieren mehrere Hypothesen. Die Einteilung der HT-Patienten gemäß ihrer Schilddrüsenautoantikörper-Titer in Subkollektive ergab keinen Hinweis auf einen Einfluss der Aktivität des Autoimmungeschehens auf die Häufigkeit der Kohlenhydratmalassimilation. Es steht zur Diskussion, ob die HT zur Entstehung einer Kohlenhydratmalassimilation führen, oder ob eine vorbestehende Kohlenhydratmalassimilation, im Sinne eines neu identifizierten Risikofaktors, zur Genese einer HT prädisponieren könnte. In der vorliegenden Studie konnte erstmalig eine signifikante Häufung der Kohlenhydratmalassimilation bei euthyreoten HT-Patienten aufgezeigt werden. Vor dem Hintergrund der weitreichenden lebensmittelindustriellen Verwendung und des hohen Konsums der Kohlenhydrate Fruktose, Laktose und Sorbitol sowie der hohen Prävalenz und Inzidenz der HT, ergibt sich eine hohe Relevanz des hier nachgewiesenen Zusammenhangs. In der differenzialdiagnostischen Abklärung gastrointestinaler Beschwerden bei euthyreoten HT-Patienten nimmt die hier beschriebene Assoziation zwischen der HT und der Kohlenhydratmalassimilation einen besonderen Stellenwert ein. Die Kohlenhydratmalassimilation verkörpert einen neuen, sowohl klinisch, als auch potentiell pathogenetisch relevanten Aspekt der Hashimotothyreoiditis. N2 - Background/Objectives: Hashimoto’s thyroiditis (HT) represents a wide-spread autoimmune disease. In euthyroid patients with HT, an impaired assimilation of common carbohydrates has been observed. Our objectives were to compare the frequency of (1) fructose (FM), lactose (LM) and sorbitol malassimilation (SM), (2) gastrointestinal symptoms (GS) following carbohydrate ingestion and (3) recurrent GS relevant to the participants’ daily lives. Subjects/Methods: We conducted a prospective case–control study of 45 ambulatory patients with HT and 38 healthy volunteers, matched with regard to age, gender and area of origin. Hydrogen breath tests with fructose, lactose, sorbitol and glucose were performed, the lactose testing additionally comprising measurements of capillary blood glucose (cBG). GS during the tests and recurrent GS concerning the participants’ daily lives were assessed. A food-frequency questionnaire was administered. Results: FM was diagnosed in 48.9% of patients compared with 26.3% of the control group (P=0.035). In all, 42.2% of patients with HT and 21.1% of healthy controls showed LM (P=0.04). FM and/or LM was present in 73.3% of the patients and in 42.1% of healthy controls (P=0.004). GS after the ingestion of fructose (P=0.003) or lactose (P=0.025) and recurrent GS were significantly more prevalent in the case group. The consumption of free fructose, lactose or sorbitol did not differ. Conclusions: Carbohydrate malassimilation and gastrointestinal complaints are frequent in euthyroid patients with HT, leading to novel clinical and pathophysiological considerations and concepts. KW - Schilddrüse KW - Malabsorption KW - Fructose KW - Lactose KW - Hashimoto-Thyreoiditis KW - Malassimilation KW - Hashimoto Thyreoiditis KW - Kohlenhydrate KW - Schilddrüse KW - Fruktose KW - fructose KW - thyroid KW - carbohydrate KW - malassimilation KW - lactose Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-140362 ER - TY - THES A1 - Heider, Melanie T1 - Detektionsrate der \(^{68}\)Ga-PSMA-PET/CT bei Patienten mit Rezidiv eines Prostatakarzinoms und Androgendeprivationstherapie T1 - Detection Rate of \(^{68}\)Ga-PSMA Ligand PET/CT in Patients with Recurrent Prostate Cancer and Androgen Deprivation Therapy N2 - Die Detektion des Prostataspezifischen Membranantigens (PSMA) mittels kombinierter Positronenemissions- und Computertomographie (PET/CT) ist ein etabliertes diagnostisches Verfahren bei Patienten mit Prostatakarzinom. Hierbei ist bislang unklar, ob und wie eine bereits eingeleitete Androgendeprivationstherapie (ADT) die diagnostische Genauigkeit der PSMA-PET/CT beeinflusst. Ziel dieser Arbeit war es, die Detektionsrate der PSMA-PET/CT mit 68Ga-PSMA I&T unter ADT in Abhängigkeit des PSA-Wertes zu evaluieren und mit einer Kontrollgruppe ohne ADT zu vergleichen. In dieser retrospektiven Studie wurden Daten von Patienten mit biochemischem Rezidiv nach radikaler Prostatektomie analysiert, welche zwischen 2014 und 2018 eine PSMA-PET/CT am Universitätsklinikum Würzburg erhalten haben. Mittels Propensity Score Matching wurde für die Patienten mit ADT innerhalb der letzten 6 Monate vor Durchführung der PSMA-PET/CT eine Kontrollgruppe ohne ADT erstellt. Die Patienten mit ADT (n=62) wiesen eine signifikant höhere Detektionsrate auf als die Patienten ohne ADT (n=62). Die Traceranreicherung unterschied sich nicht signifikant in beiden Gruppen. Dagegen wiesen die Patienten mit ADT jedoch eine signifikant höhere Tumorlast auf und hatten häufiger Knochen- und Organmetastasen, sodass als Ursache für die höhere Detektionsrate der PSMA-PET/CT bei Patienten mit ADT ein fortgeschritteneres Tumorstadium angenommen wurde. Die Detektionsrate war bei den Patienten mit ADT auch bei niedrigen PSA-Werten hoch. Es scheint daher nicht erforderlich zu sein, eine bestehende ADT vor Durchführung der PSMA-PET/CT im biochemischen Rezidiv abzusetzen und damit das Risiko einer Krankheitsprogression einzugehen. Die Korrelation des PSA-Wertes mit der Tumorlast in der PSMA-PET/CT war bei Patienten mit ADT geringer ausgeprägt als bei Patienten ohne ADT. Patienten unter ADT könnten daher von einer regelmäßigen Durchführung der PSMA-PET/CT zur Überwachung der Krankheitsprogression profitieren. Hier bleibt allerdings eine Kosten-Nutzen-Analyse abzuwarten, da dies deutlich aufwendiger und teurer ist als die Bestimmung des PSA-Wertes. N2 - Detection of prostate specific membrane antigen (PSMA) by combined positron emission tomography and computed tomography (PET/CT) is an established diagnostic procedure in patients with prostate cancer. So far it is unclear whether an already initiated androgen deprivation therapy (ADT) influences the diagnostic accuracy of PSMA-PET/CT. The aim of this study was to evaluate the effect of ADT on the detection rate of PSMA-PET/CT with 68Ga-PSMA I&T. In this retrospective study, data from patients with biochemical recurrence after radical prostatectomy who received PSMA-PET/CT at the University Hospital of Würzburg between 2014 and 2018 were analyzed. Propensity score matching was used to create two balanced groups of 62 patients who either did or did not receive ADT within six months before imaging. The detection rate of PSMA-PET/CT was significantly higher in the group of patients with ADT than in the control group without ADT. Tracer accumulation was not significantly different in both groups. In contrast, patients with ADT had significantly higher tumor burden and more frequent bone and organ metastases, suggesting a more advanced disease stage as the reason for the higher detection rate of PSMA-PET/CT in patients with ADT. The detection rate was high in patients with ADT even at low PSA levels. Therefore, the withdrawal of ADT before PSMA-PET/CT in biochemical recurrence, thereby risking disease progression, cannot be recommended. The correlation of PSA level with tumor burden in PSMA-PET/CT is lower in patients with ADT than in patients without ADT. Patients with ADT may therefore benefit from routine performance of PSMA-PET/CT to monitor disease progression. However, a cost-benefit analysis remains to be performed, as this is significantly more time-consuming and expensive than the measuring of the PSA value. KW - Positronen-Emissions-Tomografie KW - Detektion KW - Computertomografie KW - Prostatakrebs KW - Rezidiv KW - Androgendeprivation KW - Prostataspezifisches Membranantigen Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-306123 ER - TY - THES A1 - Heinrich, Marieke T1 - Bildgebung des Prostatakarzinoms im PSMA-PET/CT: Die halbautomatische Quantifizierung des Tumorvolumens zeigt (noch) keine verbesserte Prädiktion des Krankheitsverlaufs T1 - Imaging of prostate cancer in PSMA-PET/CT: Semi-automatic quantification of tumor volume does not (yet) show any improved prediction of disease progression N2 - Die molekularen Parameter PSMA-TV und TL-PSMA im 68Ga-PSMA PET/CT leiten sich ab von MTV und TLG im FDG PET/CT. Mit der vorliegenden Arbeit wurden die Grenzen neuer Autosegmentierungsprogramme durch eine maximale Belastung mit großen Tumorvolumina von Patienten unter taxanbasierter Chemotherapie ausgelotet. Die Programme Syngo.via und FIJI kamen zu vergleichbaren Ergebnissen. Patienten mit einem Gleason Score von 8-10 zeigten unter Therapie eine signifikante Zunahme des PSMA-TV und TL-PSMA im Gegensatz zu Patienten mit Gleason Score 6-7b. Ein hoher PSA-Wert korrelierte zu allen Zeitpunkten signifikant mit einem hohen PSMA-TV und TL-PSMA, ebenso korrelierte ein steigender PSA-Wert signifikant mit steigenden Werten in PSMA-TV und TL-PSMA. Patienten mit einem biochemischen Progress und einem Progress nach modifiziertem PERCIST zeigten vor Therapie ein signifikant höheres PSMA-TV und TL-PSMA als Patienten ohne Progress und unter Therapie eine signifikante Zunahme des PSMA-TV und TL-PSMA im Vergleich zu Patienten ohne Progress. Eine Einteilung des Therapieansprechens aller Patienten in CR, PR, SD und PD nach PSMA-TV, TL-PSMA, PSA-Wert und modifiziertem PERCIST stimmte nicht in allen Patienten überein. Ein signifikant kürzeres Gesamtüberleben zeigten lediglich Patienten mit einem nach dem PSA-Wert definiertem Progress. Im praktischen Vergleich der beiden Programme benötigte Syngo.via für eine komplette Segmentierung signifikant mehr Zeit als FIJI, vor allem da der Wechsel von VOI zu VOI signifikant länger dauerte. Unabhängig vom Autosegmentierungsprogramm dauerte eine komplette Segmentierung länger, je größer das PSMA-TV und das TL-PSMA war, je mehr VOIs das Programm automatisch setzte und je mehr VOIs manuell gelöscht und neu gesetzt wurden. In der Gesamtschau bieten PSMA-TV und TL-PSMA in Kombination mit den sich schnell weiterentwickelnden Autosegmentierungs-Programmen die Möglichkeit, auch sehr hohe Tumorlasten des PCas objektiv und vergleichbar zu beschreiben. N2 - The molecular parameters PSMA-TV and TL-PSMA in 68Ga-PSMA PET/CT are derived from MTV and TLG in FDG PET/CT. The present work explored the limits of new autosegmentation programs with large tumor volumes from patients receiving taxane-based chemotherapy. The programs Syngo.via and FIJI achieved comparable results. Patients with a Gleason score of 8-10 showed a significant increase in PSMA-TV and TL-PSMA during therapy in contrast to patients with Gleason scores 6-7b. A high PSA value was significantly correlated with a high PSMA-TV and TL-PSMA at all time points, and an increasing PSA value was also significantly correlated with increasing values in PSMA-TV and TL-PSMA. Patients with biochemical progression and progression according to modified PERCIST showed a significantly higher PSMA-TV and TL-PSMA before therapy than patients without progression and a significant increase in PSMA-TV and TL-PSMA during therapy compared to patients without progression. A classification of therapy response in all patients into CR, PR, SD and PD based on PSMA-TV, TL-PSMA, PSA value and modified PERCIST was not consistent in all patients. Only patients with progression defined by the PSA value showed a significantly shorter overall survival. In a practical comparison of the two programs, Syngo.via required significantly more time for complete segmentation than FIJI, especially since switching from VOI to VOI took significantly longer. Regardless of the auto-segmentation program, complete segmentation took longer as the PSMA-TV and TL-PSMA increased, and as the program automatically set more VOIs and more VOIs were manually deleted and reset. Overall, PSMA-TV and TL-PSMA in combination with the rapidly developing auto-segmentation programs offer the possibility of objectively and comparably describing even very high PCa tumor burdens. KW - Hormonrefraktärer Prostatakrebs KW - Positronen-Emissions-Tomografie KW - Chemotherapie KW - Tumorvolumen Y1 - 2024 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-359684 ER - TY - JOUR A1 - Heinze, Britta A1 - Schirbel, Andreas A1 - Nannen, Lukas A1 - Michelmann, David A1 - Hartrampf, Philipp E. A1 - Bluemel, Christina A1 - Schneider, Magdalena A1 - Herrmann, Ken A1 - Haenscheid, Heribert A1 - Fassnacht, Martin A1 - Buck, Andreas K. A1 - Hahner, Stefanie T1 - Novel CYP11B-ligand [\(^{123/131}\)I]IMAZA as promising theranostic tool for adrenocortical tumors: comprehensive preclinical characterization and first clinical experience JF - European Journal of Nuclear Medicine and Molecular Imaging N2 - Purpose Adrenal tumors represent a diagnostic and therapeutic challenge. Promising results have been obtained through targeting the cytochrome P450 enzymes CYP11B1 and CYP11B2 for molecular imaging, and [\(^{123/131}\)I]iodometomidate ([\(^{123/131}\)I]IMTO) has even been successfully introduced as a theranostic agent. As this radiopharmaceutical shows rapid metabolic inactivation, we aimed at developing new improved tracers. Methods Several IMTO derivatives were newly designed by replacing the unstable methyl ester by different carboxylic esters or amides. The inhibition of aldosterone and cortisol synthesis was tested in different adrenocortical cell lines. The corresponding radiolabeled compounds were assessed regarding their stability, in vitro cell uptake, in vivo biodistribution in mice, and their binding specificity to cryosections of human adrenocortical and non-adrenocortical tissue. Furthermore, a first investigation was performed in patients with known metastatic adrenal cancer using both [\(^{123}\)I]IMTO and the most promising compound (R)-1-[1-(4-[\(^{123/}\)I]iodophenyl)ethyl]-1H-imidazole-5-carboxylic acid azetidinylamide ([\(^{123}\)I]IMAZA) for scintigraphy. Subsequently, a first endoradiotherapy with [\(^{131}\)I]IMAZA in one of these patients was performed. Results We identified three analogues to IMTO with high-affinity binding to the target enzymes and comparable or higher metabolic stability and very high and specific accumulation in adrenocortical cells in vitro and in vivo. Labeled IMAZA exhibited superior pharmacokinetic and imaging properties compared to IMTO in mice and 3 patients, too. An endoradiotherapy with [\(^{131}\)I]IMAZA induced a 21-month progression-free interval in a patient with rapidly progressing ACC prior this therapy. Conclusion We developed the new radiopharmaceutical [\(^{123/131}\)I]IMAZA with superior properties compared to the reference compound IMTO and promising first experiences in humans. KW - CYP11B enzymes KW - adrenal incidentaloma KW - adrenocortical carcinoma Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-265606 SN - 1619-7089 VL - 49 IS - 1 ER - TY - JOUR A1 - Hendricks, Anne A1 - Lenschow, Christina A1 - Kroiss, Matthias A1 - Buck, Andreas A1 - Kickuth, Ralph A1 - Germer, Christoph-Thomas A1 - Schlegel, Nicolas T1 - Evaluation of diagnostic efficacy for localization of parathyroid adenoma in patients with primary hyperparathyroidism undergoing repeat surgery JF - Langenbeck's Archives of Surgery N2 - Purpose Repeat surgery in patients with primary hyperparathyroidism (pHPT) is associated with an increased risk of complications and failure. This stresses the need for optimized strategies to accurately localize a parathyroid adenoma before repeat surgery is performed. However, evidence on the extent of required diagnostics for a structured approach is sparse. Methods A retrospective single-center evaluation of 28 patients with an indication for surgery due to pHPT and previous thyroid or parathyroid surgery was performed. Diagnostic workup, surgical approach, and outcome in terms of complications and successful removement of parathyroid adenoma with biochemical cure were evaluated. Results Neck ultrasound, sestamibi scintigraphy, C11-methionine PET-CT, and selective parathyroid hormone venous sampling, but not MRI imaging, effectively detected the presence of a parathyroid adenoma with high positive predictive values. Biochemical cure was revealed by normalization of calcium and parathormone levels 24-48h after surgery and was achieved in 26/28 patients (92.9%) with an overall low rate of complications. Concordant localization by at least two diagnostic modalities enabled focused surgery with success rates of 100%, whereas inconclusive localization significantly increased the rate of bilateral explorations and significantly reduced the rate of biochemical cure to 80%. Conclusion These findings suggest that two concordant diagnostic modalities are sufficient to accurately localize parathyroid adenoma before repeat surgery for pHPT. In cases of poor localization, extended diagnostic procedures are warranted to enhance surgical success rates. We suggest an algorithm for better orientation when repeat surgery is intended in patients with pHPT. KW - Primary hyperparathyroidism (pHPT) KW - preoperative localization KW - repeat surgery KW - diagnostics KW - imaging Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-267520 SN - 1435-2451 VL - 406 IS - 5 ER - TY - JOUR A1 - Herrmann, Ken A1 - Buck, Andreas K. A1 - Schuster, Tibor A1 - Abbrederis, Kathrin A1 - Blümel, Christina A1 - Santi, Ivan A1 - Rudelius, Martina A1 - Wester, Hans-Jürgen A1 - Peschel, Christian A1 - Schwaiger, Markus A1 - Dechow, Tobias A1 - Keller, Ulrich T1 - Week one FLT-PET response predicts complete remission to R-CHOP and survival in DLBCL JF - Oncotarget N2 - Despite improved survival in the Rituximab (R) era, a considerable number of patients with diffuse large B-cell lymphoma (DLBCL) ultimately die from the disease. Functional imaging using [18F]fluorodeoxyglucose-PET is suggested for assessment of residual viable tumor very early during treatment but is compromised by non-specific tracer retention in inflammatory lesions. The PET tracer [18F]fluorodeoxythymidine (FLT) as surrogate marker of tumor proliferation may overcome this limitation. We present results of a prospective clinical study testing FLT-PET as superior and early predictor of response to chemotherapy and outcome in DLBCL. 54 patients underwent FLT-PET prior to and one week after the start of R-CHOP chemotherapy. Repetitive FLT-PET imaging was readily implemented into the diagnostic work-up. Our data demonstrate that the reduction of FLT standard uptake valuemean (SUVmean) and SUVmax one week after chemotherapy was significantly higher in patients achieving complete response (CR, n=48; non-CR, n=6; p<0.006). Martingale-residual and Cox proportional hazard analyses showed a significant monotonous decrease of mortality risk with increasing change in SUV. Consistent with these results, early FLT-PET response showed relevant discriminative ability in predicting CR. In conclusion, very early FLT-PET in the course of R-CHOP chemotherapy is feasible and enables identification of patients at risk for treatment failure. KW - [18F]Fluorodeoxythymidine KW - FLT-PET KW - positron emission tomography KW - DLBCL KW - lymphoma Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-120659 SN - 1949-2553 VL - 5 IS - 12 ER - TY - JOUR A1 - Herrmann, Ken A1 - Queiroz, Marcelo A1 - Huellner, Martin W. A1 - Barbosa, Felipe de Galiza A1 - Buck, Andreas A1 - Schaefer, Niklaus A1 - Stolzman, Paul A1 - Veit-Haibach, Patrick T1 - Diagnostic performance of FDG-PET/MRI and WB-DW-MRI in the evaluation of lymphoma: a prospective comparison to standard FDG-PET/CT JF - BMC Cancer N2 - Background: Use of FDG-PET/CT for staging and restaging of lymphoma patients is widely incorporated into current practice guidelines. Our aim was to prospectively evaluate the diagnostic performance of FDG-PET/MRI and WB-DW-MRI compared with FDG-FDG-PET/CT using a tri-modality PET/CT-MRI system. Methods: From 04/12 to 01/14, a total of 82 FDG-PET/CT examinations including an additional scientific MRI on a tri-modality setup were performed in 61 patients. FDG-PET/CT, FDG-PET/MRI, and WB-DW-MRI were independently analyzed. A lesion with a mean ADC below a threshold of 1.2 x 10\(^{-3}\) mm\(^2\)/s was defined as positive for restricted diffusion. FDG-PET/CT and FDG-PET/MRI were evaluated for the detection of lesions corresponding to lymphoma manifestations according to the German Hodgkin Study Group. Imaging findings were validated by biopsy (n = 21), by follow-up imaging comprising CT, FDG-PET/CT, and/or FDG-PET/MRI (n = 32), or clinically (n = 25) (mean follow-up: 9.1 months). Results: FDG-PET/MRI and FDG-PET/CT accurately detected 188 lesions in 27 patients. Another 54 examinations in 35 patients were negative. WB-DW-MRI detected 524 lesions, of which 125 (66.5 % of the aforementioned 188 lesions) were true positive. Among the 188 lesions positive for lymphoma, FDG-PET/MRI detected all 170 instances of nodal disease and also all 18 extranodal lymphoma manifestations; by comparison, WB-DW-MRI characterized 115 (67.6 %) and 10 (55.6 %) lesions as positive for nodal and extranodal disease, respectively. FDG-PET/MRI was superior to WB-DW-MRI in detecting lymphoma manifestations in patients included for staging (113 vs. 73), for restaging (75 vs. 52), for evaluation of high-(127 vs. 81) and low-grade lymphomas (61 vs. 46), and for definition of Ann Arbor stage (WB-DW-MRI resulted in upstaging in 60 cases, including 45 patients free of disease, and downstaging in 4). Conclusion: Our results indicate that FDG-PET/CT and FDG-PET/MRI probably have a similar performance in the clinical work-up of lymphomas. The performance of WB-DW-MRI was generally inferior to that of both FDG-PET-based methods but the technique might be used in specific scenarios, e.g., in low-grade lymphomas and during surveillance. KW - response evaluation KW - FDG-PET/MRI KW - FDG-PET/CT KW - FDG KW - WB-DW-MRI KW - whole-body KW - involvement KW - coefficient KW - lymphoma KW - B-cell lymphoma KW - diffusion weighted MRI KW - whole body MRI KW - Hodgkin-lymphoma KW - 1st International Workshop KW - malignant lymphoma KW - initial experience Y1 - 2015 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-136039 VL - 15 IS - 1002 ER - TY - JOUR A1 - Herrmann, Ken A1 - Wieder, Hinrich A. A1 - Lassmann, Michael A1 - Allen-Auerbach, Martin S. A1 - Czernin, Johannes T1 - Clinical use of bone-targeting radiopharmaceuticals with focus on alpha-emitters N2 - 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. KW - bone-targeting radiopharmaceuticals KW - Radium KW - alpha-emitters Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-113014 ER - TY - JOUR A1 - Higuchi, Takahiro A1 - Serfling, Sebastian E. A1 - Rowe, Steven P. A1 - Werner, Rudolf A. T1 - Therapeutic effects of lipid lowering medications on myocardial blood flow, inflammation, and sympathetic nerve activity using nuclear techniques JF - Current Cardiology Reports N2 - Purpose of Review Statins are routinely applied in patients with coronary artery disease, as they allow significantly to reduce blood cholesterol levels. Although those drugs are endorsed by current guidelines and prescribed routinely, a substantial portion of patients are still statin-intolerant and image-piloted strategies may then be helpful to identify patients that need further intensified treatment, e.g., to initiate treatment with proprotein convertase subtilisin / kexin type 9 inhibitors (PCSK9i). In addition, it has also been advocated that statins exhibit nonlipid, cardio-protective effects including improved cardiac nerve integrity, blood flow, and anti-inflammatory effects in congestive heart failure (HF) patients. Recent Findings In subjects after myocardial infarction treated with statins, \(^{123}\)I-metaiodobenzylguanidine (MIBG) scintigraphy has already revealed enhanced cardiac nerve function relative to patients without statins. In addition, all of those aforementioned statin-targeted pathways in HF can be visualized and monitored using dedicated cardiac radiotracers, e.g., \(^{123}\)I-MIBG or \(^{18}\)F-AF78 (for cardiac nerve function), \(^{18}\)F-flurpiridaz (to determine coronary flow) or \(^{68}\)Ga-PentixaFor (to detect inflammation). Summary Statins exhibit various cardio-beneficial effects, including improvement of cardiac nerve function, blood flow, and reduction of inflammation, which can all be imaged using dedicated nuclear cardiac radiotracers. This may allow for in vivo monitoring of statin-induced cardioprotection beyond lipid profiling in HF patients. KW - sympathetic nervous system KW - cardiac nerve KW - MIBG KW - inflammation KW - blood flow KW - statin Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-324599 VL - 24 IS - 12 ER - TY - JOUR A1 - Higuchi, Takahiro A1 - Werner, Rudolf A. T1 - Unfolding the cardioprotective potential of sigma-1 receptor-directed molecular imaging JF - Journal of Nuclear Cardiology N2 - No abstract available. KW - Journal of Nuclear Cardiology KW - editorial KW - sigma-1 receptor-directed molecular imaging KW - cardioprotective potential Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-324600 VL - 30 IS - 2 ER - TY - THES A1 - Hildebrandt, Lysann T1 - Das Verhältnis von Muskel- und Knochenmasse bei Kindern und jungen Erwachsenen mit Anorexia nervosa, Hypophosphatasie, Kraniopharyngeom und rheumatischen Erkrankungen T1 - The relation of muscle mass and osseous mass with children and young adult with anorexia nervosa, hypophosphatasia, craniopharyngeoma and rheumatism illnesses N2 - Ziel der Studie lag in der Analyse des Zusammenhangs von Muskel- und Knochenmasse als Surrogat für Kraft und Knochenfestigkeit. In der vorliegenden Arbeit wurden 265 gesunde und chronisch kranke Kinder und Jugendliche auf ihre Körperzusammensetzung untersucht.(Anorexia nervosa: 40, Hypophosphatasie: 10, Kraniopharyngeom: 12 und juveniles Rheuma: 68, Referenzgruppe: 79 gesunde weissrussische Mädchen und 56 Jungen). Die Untersuchungsergebnisse der DXA Messungen bestätigen , dass die Knochenmasse als Surrogat für Festigkeit eng mit der Muskelmasse korreliert. Mit zunehmender Muskelmasse steigt auch der BMC an. Die Ergebnisse der Studie stehen im Einklang mit dem von Frost postuliertem Regelkreis, der einen kausalen Zusammenhang zwischen Muskelkraft und Knochenfestigkeit beschrieb. Generell zeigte sich, dass das Surrogat Knochendichte diesen Zusammenhang weniger scharf beschreibt als die Knochenmasse. Darüber hinaus fanden sich Störungen des Regelkreises, deren Ursachen zum Teil Gegenstand der Abklärung in weiterführenden Studien bleiben. N2 - The aim of the study lay in the analysis of the connection of muscle mass and osseous mass as a surrogate for strength and osseous firmness. In the present work 265 became recovers and chronically ill children and youngsters on her body composition examined. (anorexia nervosa: 40, hypophosphatasia: 10, craniopharyngeoma: 12 and juvenile rheumatisms: 68, authoritative group: 79 healthy Belorussian girls and 56 boys). The investigation results of the measurements DXA confirm that the osseous mass correlates as a surrogate for firmness closely with the muscle mass. With increasing muscle mass also rises of the BMC. The results of the study stand in the harmony with the control circuit postulated by „Frost“ which described a causal connection between muscular strength and osseous firmness.In general appeared that the surrogate describes osseous density this connection less sharply than the osseous mass. In addition, disturbances of the control circuit whose causes remain partly an object of the clarification in continuing studies were found. KW - Knochenstoffwechsel KW - Knochen KW - Knochenartefakt KW - Muskelstoffwechsel KW - Appetitlosigkeit KW - Rheumatismus KW - Deutsche Rheuma-Liga KW - Osteologie KW - Kraniopharyngiom KW - Cortison KW - Rheumatismus KW - Deutsche Rheuma-Liga KW - Osteologie KW - Kraniopharyngiom KW - Cortison KW - Rheumatism KW - German rheumatic league KW - Osteologie KW - Craniopharyngioma KW - Cortison Y1 - 2008 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-30414 ER - TY - JOUR A1 - Hoffmann, Jan V. A1 - Janssen, Jan P. A1 - Kanno, Takayuki A1 - Shibutani, Takayuki A1 - Onoguchi, Masahisa A1 - Lapa, Constantin A1 - Grunz, Jan-Peter A1 - Buck, Andreas K. A1 - Higuchi, Takahiro T1 - Performance evaluation of fifth-generation ultra-high-resolution SPECT system with two stationary detectors and multi-pinhole imaging JF - EJNMMI Physics N2 - Background Small-animal single-photon emission computed tomography (SPECT) systems with multi-pinhole collimation and large stationary detectors have advantages compared to systems with moving small detectors. These systems benefit from less labour-intensive maintenance and quality control as fewer prone parts are moving, higher accuracy for focused scans and maintaining high resolution with increased sensitivity due to focused pinholes on the field of view. This study aims to investigate the performance of a novel ultra-high-resolution scanner with two-detector configuration (U-SPECT5-E) and to compare its image quality to a conventional micro-SPECT system with three stationary detectors (U-SPECT\(^+\)). Methods The new U-SPECT5-E with two stationary detectors was used for acquiring data with \(^{99m}\)Tc-filled point source, hot-rod and uniformity phantoms to analyse sensitivity, spatial resolution, uniformity and contrast-to-noise ratio (CNR). Three dedicated multi-pinhole mouse collimators with 75 pinholes each and 0.25-, 0.60- and 1.00-mm pinholes for extra ultra-high resolution (XUHR-M), general-purpose (GP-M) and ultra-high sensitivity (UHS-M) imaging were examined. For CNR analysis, four different activity ranges representing low- and high-count settings were investigated for all three collimators. The experiments for the performance assessment were repeated with the same GP-M collimator in the three-detector U-SPECT\(^+\) for comparison. Results Peak sensitivity was 237 cps/MBq (XUHR-M), 847 cps/MBq (GP-M), 2054 cps/MBq (UHS-M) for U-SPECT5-E and 1710 cps/MBq (GP-M) for U-SPECT\(^+\). In the visually analysed sections of the reconstructed mini Derenzo phantoms, rods as small as 0.35 mm (XUHR-M), 0.50 mm (GP-M) for the two-detector as well as the three-detector SPECT and 0.75 mm (UHS-M) were resolved. Uniformity for maximum resolution recorded 40.7% (XUHR-M), 29.1% (GP-M, U-SPECT5-E), 16.3% (GP-M, U-SPECT\(^+\)) and 23.0% (UHS-M), respectively. UHS-M reached highest CNR values for low-count images; for rods smaller than 0.45 mm, acceptable CNR was only achieved by XUHR-M. GP-M was superior for imaging rods sized from 0.60 to 1.50 mm for intermediate activity concentrations. U-SPECT5-E and U-SPECT+ both provided comparable CNR. Conclusions While uniformity and sensitivity are negatively affected by the absence of a third detector, the investigated U-SPECT5-E system with two stationary detectors delivers excellent spatial resolution and CNR comparable to the performance of an established three-detector-setup. KW - small-animal imaging KW - SPECT KW - mouse KW - ollimator KW - post-reconstruction filtering Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-230361 VL - 7 ER - TY - THES A1 - Hoffmann, Jan Vincent T1 - Small-animal SPECT with Two Stationary Detectors: Performance Evaluation and Image Quality Assessment of Multi-pinhole Collimators T1 - Kleintier-SPECT mit Zwei Stationären Detektoren: Leistungsbewertung und Bildqualitätsanalyse von Multipinhole-Kollimatoren N2 - SPECT as a representative of molecular imaging allows visualization of metabolic processes in vivo. In clinical practice, single photon emission imaging is an established modality for myocardial perfusion imaging or the diagnosis of adrenal or neuroendocrine tumors, to name a few. With technical advances in scanner design and data processing leading to improved spatial resolution and image quality, SPECT has become a serious contender in small animal preclinical imaging. With multi-pinhole collimation, submillimeter spatial resolutions are achieved without limiting sensitivity, which has led to a significant increase of interest in SPECT for preclinical research in recent years. In this dissertation, the potential of a two-detector system through an analysis of three dedicated mouse collimators with multi-pinhole configurations was demonstrated. For this, sensitivity, spatial resolution, and uniformity as key parameters were determined. In the second part of the present work, an evaluation of the image quality at different activity concentrations to allow prediction of the system performance related to in vivo studies was performed. Therefore, a visual evaluation, as well as a calculation of the contrastto-noise ratio, was performed using mini Derenzo phantoms for the respective three mouse collimators. To better classify the results, the study was extended by a comparison with the predecessor system. Due to the absence of the third bottom detector, sensitivity and uniformity are slightly compromised. All three collimators were able to achieve a spatial resolution in the submillimeter range, XUHR-M offers a peak resolution of up to 0.35 mm. In terms of resolution, both evaluated systems performed on an equal level. Visual assessment of image quality indicates a slight advantage of the new two-detector system, and the contrast-to-noise ratio seems to benefit from the improved SROSEM algorithm. However, the differences between the two systems are marginal. The U-SPECT5/CT E-Class is proven to be state-of-the-art for small animal imaging and is a powerful instrument for preclinical molecular imaging research. Improvements in system design compensate well for the reduction in the detection area, allowing excellent imaging even with low activity concentrations. N2 - SPECT als Vertreter der molekularen Bildgebung ermöglicht die Visualisierung von Stoffwechselprozessen in vivo. In der klinischen Praxis ist die Einzelphotonen-Emissions-Bildgebung eine etablierte Modalität für die Myokard-Perfusions-Bildgebung oder die Diagnose von Nebennieren- oder neuroendokrinen Tumoren, um nur einige Beispiele zu nennen. Mit den technischen Fortschritten bei der Konstruktion von Scannern und der Datenverarbeitung, die zu einer verbesserten räumlichen Auflösung und Bildqualität führen, ist SPECT zu einem ernstzunehmenden Mitbewerber in der präklinischen Bildgebung von Kleintieren geworden. Unter der Verwendung von Multipinhole-Kollimatoren lassen sich Ortsauflösungen von unter einem Millimeter erzielen, ohne die Sensitivität deutlich einzuschränken. Dies trug dazu bei, dass das Interesse an SPECT in der präklinischen Forschung in den letzten Jahren zugenommen hat. In dieser Dissertation wurde das Potenzial eines Zweidetektorsystems unter Verwendung von drei Multipinhole-Mauskollimatoren evaluiert. Zur Leistungsbewertung wurde Sensitivität, Ortsauflösung und Homogenität bestimmt. Im zweiten Teil dieser Arbeit wurde eine Analyse der Bildqualität mit verschiedenen Aktivitätskonzentrationen durchgeführt, um eine Vorhersage der Leistung des Systems in In-vivo-Studien zu ermöglichen. Dazu wurde eine visuelle Bewertung sowie eine Berechnung des Kontrast-zu-Rausch-Verhältnisses mit Mini-Derenzo-Phantomen für die entsprechenden drei Mauskollimatoren durchgeführt. Um die Ergebnisse besser einordnen zu können, wurde die Studie um einen Vergleich mit dem Vorgängersystem erweitert. Durch das Fehlen des dritten unteren Detektors sind Sensitivität und Homogenität leicht beeinträchtigt. Alle drei Kollimatoren konnten eine Ortsauflösung unter einem Millimeter erreichen, wobei XUHR-M die höchste Auflösung von bis zu 0.35 mm erreicht. Die beiden untersuchten Systeme sind hinsichtlich der Ortsauflösung gleichwertig. Die visuelle Bewertung der Bildqualität deutet auf einen leichten, jedoch nur marginalen Vorteil des neuen Zweidetektorsystems hin, und das Kontrast-zu-Rausch-Verhältnis scheint von dem verbesserten SROSEM-Algorithmus zu profitieren. Das U-SPECT5/CT E-Class ist nachweislich auf dem neuesten Stand der Technik für die Bildgebung bei Kleintieren und ein leistungsfähiges Instrument für die präklinische Forschung. Das System kompensiert die Reduktion der Detektionsfläche und ermöglicht eine hervorragende Bildgebung auch bei geringen Aktivitätskonzentrationen. KW - SPECT KW - small-animal SPECT KW - performance evaluation KW - multi-pinhole collimation Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-328195 ER - TY - JOUR A1 - Hänscheid, Heribert A1 - Hartrampf, Philipp E. A1 - Schirbel, Andreas A1 - Buck, Andreas K. A1 - Lapa, Constantin T1 - Intraindividual comparison of [\(^{177}\)Lu]Lu-DOTA-EB-TATE and [\(^{177}\)Lu]Lu-DOTA-TOC JF - European Journal of Nuclear Medicine and Molecular Imaging N2 - Purpose The radiolabelled somatostatin analogue [\(^{177}\)Lu]Lu-DOTA-EB-TATE binds to albumin via Evans blue, thereby increasing the residence time in the blood and potentially allowing more therapeutic agent to be absorbed into the target tissue during peptide receptor radionuclide therapy. It was tested in selected patients whether the substance is superior to [\(^{177}\)Lu]Lu-DOTA-TOC. Methods Activity kinetics in organs and tumours after [\(^{177}\)Lu]Lu-DOTA-EB-TATE and [\(^{177}\)Lu]Lu-DOTA-TOC were compared intraindividually in five patients with progressive somatostatin receptor-positive disease scheduled for radionuclide therapy. Resuluts In comparison to [\(^{177}\)Lu]Lu-DOTA-TOC, tumour doses per administered activity were higher for [\(^{177}\)Lu]Lu-DOTA-EB-TATE in 4 of 5 patients (median ratio: 1.7; range: 0.9 to 3.9), kidney doses (median ratio: 3.2; range: 1.6 to 9.8) as well as spleen doses (median ratio: 4.7; range 1.2 to 6.2) in all patients, and liver doses in 3 of 4 evaluable patients (median ratio: 4.0; range: 0.7 to 4.9). The tumour to critical organs absorbed dose ratios were higher after [\(^{177}\)Lu]Lu-DOTA-TOC in 4 of 5 patients. Conclusions Prior to a treatment with [\(^{177}\)Lu]Lu-DOTA-EB-TATE, it should be assessed individually whether the compound is superior to established substances. KW - intraindividual comparison KW - DOTA-EB-TATE KW - somatostatin receptor KW - evans blue KW - biokinetics Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-265470 SN - 1619-7089 VL - 48 IS - 8 ER - TY - THES A1 - Hüller, Mareike T1 - Stellenwert der basalen im Vergleich zur Pentagastrin-stimulierten Kalzitoninbestimmung in der Nachsorge des C-Zellkarzinoms T1 - Significance of basal Calcitonin compared to Pentagastrin-stimulated calcitonin in the follow-up of patients with medullary thyroid carcinoma N2 - Der spezifischste und sensitivste biochemische Tumormarker in der Diagnostik und Verlaufskontrolle des MTC ist Kalzitonin. Der hCT-Spiegel sollte nach totaler Thyreoidektomie nicht mehr messbar sein. Ein messbares hCT weist nach Therapie auf ein Rezidiv oder eine Metastasierung hin. Die hCT-Sekretion kann durch Gastrin stimuliert werden, was beim Pentagastrin-Stimulationstest genutzt wird. Im Rahmen dieser Arbeit wurde untersucht, welchen Stellenwert die Bestimmung des basalen Kalzitonin im Vergleich zum Pentagastrin-stimulierten hCT in der Nachsorge des MTC einnimmt. Hierzu wurden 129 Pentagastrintests von MTC-Patienten der Klinik und Poliklinik für Nuklearmedizin der Universität Würzburg retrospektiv ausgewertet. Bei sechs Prozent der Patienten fand sich nach anfänglicher biochemischer Remission ein hCT-Anstieg. Die im Pentagastrintest stimulierten hCT-Werte zeigten den Anstieg früher an als die lediglich basal gemessenen Werte. Das Ergebnis dieser Arbeit lässt den Schluss zu, dass der Pentagastrintest weiterhin ein wichtiger Bestandteil in der Nachsorge von Patienten mit MTC ist, da die stimulierten hCT-Werte im Einzelfall eine noch subklinische residuelle Erkrankung, Metastasierung oder ein Rezidiv frühzeitig detektieren. N2 - Calcitonin is the most specific and most sensitive biochemical marker in diagnostic investigation and follow up of patients with medullary thyroid carcinoma. hCT-level should be incapable of measurement after complete thyroidectomie. A measurable hCT after therapy indicates recrudescence or metastases. hCT-secretion can be stimulated by gastrin, which is used in the pentagastrin-stimulationtest. In the context of this study the significance of basal calcitonin compared to pentagastrin-stimulated hCT in the after-care of patients with medullary thyroid carcinoma was analysed. Therefore 129 pentagastrin-tests of MTC-patients from the ´Klinik und Poliklinik für Nuklearmedizin der Universität Würzburg´ were evaluated retrospectively. In a percentage of 6 an increase of hCT could be found after initial biochemical remission. The pentagastrin-stimulated hCT-values indicated the increase earlier than the basal values. To draw a conclusion the pentagastrin-stimulationtest remains an important component in the follow-up of patients with MTC because stimulated hCT-levels can - in individual cases - detect subclinical residual disease, metastases or recrudescence early. KW - Calcitonin KW - basales Calcitonin KW - stimuliertes Calcitonin KW - Pentagastrin-Stimulationstest KW - medulläres Schilddrüsencarcinom KW - basal calcitonin KW - stimulated calcitonin KW - Pentagastrin-stimulationtest KW - medullary thyroid carcinoma Y1 - 2009 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-37292 ER - TY - JOUR A1 - Ip, Chi Wang A1 - Isaias, Ioannis U. A1 - Kusche-Tekin, Burak B. A1 - Klein, Dennis A1 - Groh, Janos A1 - O´Leary, Aet A1 - Knorr, Susanne A1 - Higuchi, Takahiro A1 - Koprich, James B. A1 - Brotchie, Jonathan M. A1 - Toyka, Klaus V. A1 - Reif, Andreas A1 - Volkmann, Jens T1 - Tor1a+/- mice develop dystonia-like movements via a striatal dopaminergic dysregulation triggered by peripheral nerve injury JF - Acta Neuropathologica Communications N2 - Isolated generalized dystonia is a central motor network disorder characterized by twisted movements or postures. The most frequent genetic cause is a GAG deletion in the Tor1a (DYT1) gene encoding torsinA with a reduced penetrance of 30-40 % suggesting additional genetic or environmental modifiers. Development of dystonia-like movements after a standardized peripheral nerve crush lesion in wild type (wt) and Tor1a+/- mice, that express 50 % torsinA only, was assessed by scoring of hindlimb movements during tail suspension, by rotarod testing and by computer-assisted gait analysis. Western blot analysis was performed for dopamine transporter (DAT), D1 and D2 receptors from striatal and quantitative RT-PCR analysis for DAT from midbrain dissections. Autoradiography was used to assess the functional DAT binding in striatum. Striatal dopamine and its metabolites were analyzed by high performance liquid chromatography. After nerve crush injury, we found abnormal posturing in the lesioned hindlimb of both mutant and wt mice indicating the profound influence of the nerve lesion (15x vs. 12x relative to control) resembling human peripheral pseudodystonia. In mutant mice the phenotypic abnormalities were increased by about 40 % (p < 0.05). This was accompanied by complex alterations of striatal dopamine homeostasis. Pharmacological blockade of dopamine synthesis reduced severity of dystonia-like movements, whereas treatment with L-Dopa aggravated these but only in mutant mice suggesting a DYT1 related central component relevant to the development of abnormal involuntary movements. Our findings suggest that upon peripheral nerve injury reduced torsinA concentration and environmental stressors may act in concert in causing the central motor network dysfunction of DYT1 dystonia. KW - Dystonia KW - DYT1 KW - dopamine KW - peripheral injury KW - second hit Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-147839 VL - 4 IS - 108 ER - TY - JOUR A1 - Isaias, Ioannis U. A1 - Brumberg, Joachim A1 - Pozzi, Nicoló G. A1 - Palmisano, Chiara A1 - Canessa, Andrea A1 - Marotta, Giogio A1 - Volkmann, Jens A1 - Pezzoli, Gianni T1 - Brain metabolic alterations herald falls in patients with Parkinson's disease JF - Annals of Clinical and Translational Neurology N2 - Pathophysiological understanding of gait and balance disorders in Parkinson’s disease is insufficient and late recognition of fall risk limits efficacious followup to prevent or delay falls. We show a distinctive reduction of glucose metabolism in the left posterior parietal cortex, with increased metabolic activity in the cerebellum, in parkinsonian patients 6–8 months before their first fall episode. Falls in Parkinson’s disease may arise from altered cortical processing of body spatial orientation, possibly predicted by abnormal cortical metabolism. KW - Parkionson's disease KW - brain metabolic alterations Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-235982 VL - 7 IS - 4 ER - TY - JOUR A1 - Isaias, Ioannis Ugo A1 - Spiegel, Jörg A1 - Brumberg, Joachim A1 - Cosgrove, Kelly P. A1 - Marotta, Giorgio A1 - Oishi, Naoya A1 - Higuchi, Takahiro A1 - Küsters, Sebastian A1 - Schiller, Markus A1 - Dillmann, Ulrich A1 - van Dyck, Christopher H. A1 - Buck, Andreas A1 - Herrmann, Ken A1 - Schloegl, Susanne A1 - Volkmann, Jens A1 - Lassmann, Michael A1 - Fassbender, Klaus A1 - Lorenz, Reinhard A1 - Samnick, Samuel T1 - Nicotinic acetylcholine receptor density in cognitively intact subjects at an early stage of Parkinson's disease JF - Frontiers in Aging Neuroscience N2 - 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. KW - nicotinic receptors KW - Parkinson disease KW - 5IA-SPECT KW - dopamine acetylcholine KW - cognitive decline Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-119351 VL - 6 ER - TY - JOUR A1 - Israel, Ina A1 - Ohsiek, Andrea A1 - Al-Momani, Ehab A1 - Albert-Weissenberger, Christiane A1 - Stetter, Christian A1 - Mencl, Stine A1 - Buck, Andreas K. A1 - Kleinschnitz, Christoph A1 - Samnick, Samuel A1 - Sirén, Anna-Leena T1 - Combined [\(^{18}\)F]DPA-714 micro-positron emission tomography and autoradiography imaging of microglia activation after closed head injury in mice JF - Journal of Neuroinflammation N2 - Background Traumatic brain injury (TBI) is a major cause of death and disability. Neuroinflammation contributes to acute damage after TBI and modulates long-term evolution of degenerative and regenerative responses to injury. The aim of the present study was to evaluate the relationship of microglia activation to trauma severity, brain energy metabolism, and cellular reactions to injury in a mouse closed head injury model using combined in vivo PET imaging, ex vivo autoradiography, and immunohistochemistry. Methods A weight-drop closed head injury model was used to produce a mixed diffuse and focal TBI or a purely diffuse mild TBI (mTBI) in C57BL6 mice. Lesion severity was determined by evaluating histological damage and functional outcome using a standardized neuroscore (NSS), gliosis, and axonal injury by immunohistochemistry. Repeated intra-individual in vivo μPET imaging with the specific 18-kDa translocator protein (TSPO) radioligand [\(^{18}\)F]DPA-714 was performed on day 1, 7, and 16 and [\(^{18}\)F]FDG-μPET imaging for energy metabolism on days 2–5 after trauma using freshly synthesized radiotracers. Immediately after [\(^{18}\)F]DPA-714-μPET imaging on days 7 and 16, cellular identity of the [\(^{18}\)F]DPA-714 uptake was confirmed by exposing freshly cut cryosections to film autoradiography and successive immunostaining with antibodies against the microglia/macrophage marker IBA-1. Results Functional outcome correlated with focal brain lesions, gliosis, and axonal injury. [\(^{18}\)F]DPA-714-μPET showed increased radiotracer uptake in focal brain lesions on days 7 and 16 after TBI and correlated with reduced cerebral [\(^{18}\)F]FDG uptake on days 2–5, with functional outcome and number of IBA-1 positive cells on day 7. In autoradiography, [\(^{18}\)F]DPA-714 uptake co-localized with areas of IBA1-positive staining and correlated strongly with both NSS and the number of IBA1-positive cells, gliosis, and axonal injury. After mTBI, numbers of IBA-1 positive cells with microglial morphology increased in both brain hemispheres; however, uptake of [\(^{18}\)F]DPA-714 was not increased in autoradiography or in μPET imaging. Conclusions [\(^{18}\)F]DPA-714 uptake in μPET/autoradiography correlates with trauma severity, brain metabolic deficits, and microglia activation after closed head TBI. KW - neuroinflammation KW - TBI KW - immunohistochemistry KW - weight drop KW - PET KW - diffuse KW - focal KW - TSPO KW - autoradiography KW - IBA-1 Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-146606 VL - 13 IS - 140 ER - TY - JOUR A1 - Israel, Ina A1 - Riehl, Gabriele A1 - Butt, Elke A1 - Buck, Andreas K. A1 - Samnick, Samuel T1 - Gallium-68-labeled KISS1-54 peptide for mapping KISS1 receptor via PET: initial evaluation in human tumor cell lines and in tumor-bearing mice JF - Pharmaceuticals N2 - Kisspeptins (KPs, KISS1) and their receptor (KISS1R) play a pivotal role as metastasis suppressor for many cancers. Low or lost KP expression is associated with higher tumor grade, increased metastatic potential, and poor prognosis. Therefore, KP expression has prognostic relevance and correlates with invasiveness in cancers. Furthermore, KISS1R represents a very promising target for molecular imaging and therapy for KISS1R-expressing tumors. The goal of this study was to evaluate the developed KISS1-54 derivative, [\(^{68}\)Ga]KISS1-54, as a PET-imaging probe for KISS1R-expressing tumors. The NODAGA-KISS1-54 peptide was labeled by Gallium-68, and the stability of the resulting [\(^{68}\)Ga]KISS1-54 evaluated in injection solution and human serum, followed by an examination in different KISS1R-expressing tumor cell lines, including HepG2, HeLa, MDA-MB-231, MCF7, LNCap, SK-BR-3, and HCT116. Finally, [\(^{68}\)Ga]KISS1-54 was tested in LNCap- and MDA-MB-231-bearing mice, using µ-PET, assessing its potential as an imaging probe for PET. [\(^{68}\)Ga]KISS1-54 was obtained in a 77 ± 7% radiochemical yield and at a >99% purity. The [\(^{68}\)Ga]KISS1-54 cell uptake amounted to 0.6–4.4% per 100,000 cells. Moreover, the accumulation of [\(^{68}\)Ga]KISS1-54 was effectively inhibited by nonradioactive KISS1-54. In [\(^{68}\)Ga]KISS1-54-PET, KISS1R-positive LNCap-tumors were clearly visualized as compared to MDA-MB-231-tumor implant with predominantly intracellular KISS1R expression. Our first results suggest that [\(^{68}\)Ga]KISS1-54 is a promising candidate for a radiotracer for targeting KISS1R-expressing tumors via PET. KW - [\(^{68}\)]KISS1-54 KW - KISS1 receptor KW - GPR54 KW - kisspeptin KW - human tumor cell lines KW - positron emission tomography KW - PET KW - KISS1-54 Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-355898 SN - 1424-8247 VL - 17 IS - 1 ER - TY - JOUR A1 - Janssen, Jan P. A1 - Hoffmann, Jan V. A1 - Kanno, Takayuki A1 - Nose, Naoko A1 - Grunz, Jan-Peter A1 - Onoguchi, Masahisa A1 - Chen, Xinyu A1 - Lapa, Constantin A1 - Buck, Andreas K. A1 - Higuchi, Takahiro T1 - Capabilities of multi-pinhole SPECT with two stationary detectors for in vivo rat imaging JF - Scientific Reports N2 - We aimed to investigate the image quality of the U-SPECT5/CT E-Class a micro single-photon emission computed tomography (SPECT) system with two large stationary detectors for visualization of rat hearts and bones using clinically available \(^{99m}\)Tc-labelled tracers. Sensitivity, spatial resolution, uniformity and contrast-to-noise ratio (CNR) of the small-animal SPECT scanner were investigated in phantom studies using an ultra-high-resolution rat and mouse multi-pinhole collimator (UHR-RM). Point source, hot-rod, and uniform phantoms with \(^{99m}\)Tc-solution were scanned for high-count performance assessment and count levels equal to animal scans, respectively. Reconstruction was performed using the similarity-regulated ordered-subsets expectation maximization (SROSEM) algorithm with Gaussian smoothing. Rats were injected with similar to 100 MBq [\(^{99m}\)TcTc-MIBI or similar to 150 MBq [\(^{99m}\)Tc]Tc-HMDP and received multi-frame micro-SPECT imaging after tracer distribution. Animal scans were reconstructed for three different acquisition times and post-processed with different sized Gaussian filters. Following reconstruction, CNR was calculated and image quality evaluated by three independent readers on a five-point scale from 1="very poor" to 5="very good". Point source sensitivity was 567 cps/MBq and radioactive rods as small as 1.2 mm were resolved with the UHR-RM collimator. Collimator-dependent uniformity was 55.5%. Phantom CNR improved with increasing rod size, filter size and activity concentration. Left ventricle and bone structures were successfully visualized in rat experiments. Image quality was strongly affected by the extent of post-filtering, whereas scan time did not have substantial influence on visual assessment. Good image quality was achieved for resolution range greater than 1.8 mm in bone and 2.8 mm in heart. The recently introduced small animal SPECT system with two stationary detectors and UHR-RM collimator is capable to provide excellent image quality in heart and bone scans in a rat using standardized reconstruction parameters and appropriate post-filtering. However, there are still challenges in achieving maximum system resolution in the sub-millimeter range with in vivo settings under limited injection dose and acquisition time. KW - small animal SPECT KW - HMDP hydroxymethylene diphosphonate KW - skeletal KW - quality KW - scanner Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-230616 VL - 10 ER - TY - JOUR A1 - Janz, Anna A1 - Walz, Katharina A1 - Cirnu, Alexandra A1 - Surjanto, Jessica A1 - Urlaub, Daniela A1 - Leskien, Miriam A1 - Kohlhaas, Michael A1 - Nickel, Alexander A1 - Brand, Theresa A1 - Nose, Naoko A1 - Wörsdörfer, Philipp A1 - Wagner, Nicole A1 - Higuchi, Takahiro A1 - Maack, Christoph A1 - Dudek, Jan A1 - Lorenz, Kristina A1 - Klopocki, Eva A1 - Ergün, Süleyman A1 - Duff, Henry J. A1 - Gerull, Brenda T1 - Mutations in DNAJC19 cause altered mitochondrial structure and increased mitochondrial respiration in human iPSC-derived cardiomyocytes JF - Molecular Metabolism N2 - Highlights • Loss of DNAJC19's DnaJ domain disrupts cardiac mitochondrial structure, leading to abnormal cristae formation in iPSC-CMs. • Impaired mitochondrial structures lead to an increased mitochondrial respiration, ROS and an elevated membrane potential. • Mutant iPSC-CMs show sarcomere dysfunction and a trend to more arrhythmias, resembling DCMA-associated cardiomyopathy. Background Dilated cardiomyopathy with ataxia (DCMA) is an autosomal recessive disorder arising from truncating mutations in DNAJC19, which encodes an inner mitochondrial membrane protein. Clinical features include an early onset, often life-threatening, cardiomyopathy associated with other metabolic features. Here, we aim to understand the metabolic and pathophysiological mechanisms of mutant DNAJC19 for the development of cardiomyopathy. Methods We generated induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs) of two affected siblings with DCMA and a gene-edited truncation variant (tv) of DNAJC19 which all lack the conserved DnaJ interaction domain. The mutant iPSC-CMs and their respective control cells were subjected to various analyses, including assessments of morphology, metabolic function, and physiological consequences such as Ca\(^{2+}\) kinetics, contractility, and arrhythmic potential. Validation of respiration analysis was done in a gene-edited HeLa cell line (DNAJC19tv\(_{HeLa}\)). Results Structural analyses revealed mitochondrial fragmentation and abnormal cristae formation associated with an overall reduced mitochondrial protein expression in mutant iPSC-CMs. Morphological alterations were associated with higher oxygen consumption rates (OCRs) in all three mutant iPSC-CMs, indicating higher electron transport chain activity to meet cellular ATP demands. Additionally, increased extracellular acidification rates suggested an increase in overall metabolic flux, while radioactive tracer uptake studies revealed decreased fatty acid uptake and utilization of glucose. Mutant iPSC-CMs also showed increased reactive oxygen species (ROS) and an elevated mitochondrial membrane potential. Increased mitochondrial respiration with pyruvate and malate as substrates was observed in mutant DNAJC19tv HeLa cells in addition to an upregulation of respiratory chain complexes, while cellular ATP-levels remain the same. Moreover, mitochondrial alterations were associated with increased beating frequencies, elevated diastolic Ca\(^{2+}\) concentrations, reduced sarcomere shortening and an increased beat-to-beat rate variability in mutant cell lines in response to β-adrenergic stimulation. Conclusions Loss of the DnaJ domain disturbs cardiac mitochondrial structure with abnormal cristae formation and leads to mitochondrial dysfunction, suggesting that DNAJC19 plays an essential role in mitochondrial morphogenesis and biogenesis. Moreover, increased mitochondrial respiration, altered substrate utilization, increased ROS production and abnormal Ca\(^{2+}\) kinetics provide insights into the pathogenesis of DCMA-related cardiomyopathy. KW - cell biology KW - molecular biology KW - dilated cardiomyopathy with ataxia KW - genetics KW - metabolism KW - mitochondria KW - OXPHOS KW - ROS KW - contractility Y1 - 2024 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-350393 SN - 2212-8778 VL - 79 ER - TY - THES A1 - Janßen, Jan Paul T1 - Capabilities of a multi-pinhole SPECT system with two stationary detectors for in vivo imaging in rodents T1 - Leistungsfähigkeit eines Multi-Pinhole SPECT-Systems mit zwei stationären Detektoren zur In-vivo-Bildgebung in Nagetiermodellen N2 - Molecular imaging of rats is of great importance for basic and translational research. As a powerful tool in nuclear medicine, SPECT can be used to visualize specific functional processes in the body, such as myocardial perfusion or bone metabolism. Typical applications in laboratory animals are imaging diagnostics or the development of new tracers for clinical use. Innovations have enabled resolutions of up to a quarter of a millimeter with acceptable sensitivity. These advances have recently led to significantly more interest in SPECT both clinically and preclinically. The objective of this thesis was to evaluate the performance of the new U-SPECT5/CT E-Class by MILabs with a dedicated ultra-high resolution multi-pinhole collimator for rats and its potential for in vivo imaging of rats. The unique features of the U-SPECT are the large stationary detectors and the new iterative reconstruction algorithm. In addition, compared to the conventional system, the "E-Class" uses only two detectors instead of three. First, the sensitivity, maximum resolution, and uniformity were determined as performance parameters. Thereafter, CNRs for different activity levels comparable to those of typical in vivo activities were examined. Finally, two example protocols were carried out for imaging with 99mTc-MIBI and 99mTc-HMDP in healthy rats to evaluate the in vivo capabilities. For this purpose, CNR calculations and an image quality assessment were performed. The focus was on image quality as a function of scan time and post-reconstruction filter across a wide range of realistically achievable in vivo conditions. Performance was reasonable compared to other systems in the literature, with a sensitivity of 567 cps/MBq, a maximum resolution of 1.20 mm, and a uniformity of 55.5%. At the lower activities, resolution in phantom studies decreased to ≥1.80 mm while maintaining good image quality. High-quality bone and myocardial perfusion SPECTs were obtained in rats with a resolution of ≥1.80 mm and ≥2.20 mm, respectively. Although limited sensitivity remains a weakness of SPECT, the U-SPECT5/CT E-Class with the UHR-RM collimator can achieve in vivo results of the highest standard despite the missing third detector. Currently, it is one of the best options for high-resolution radionuclide imaging in rats. N2 - Die molekulare Bildgebung bei Ratten hat einen hohen Stellenwert in der Grundlagenforschung und der translationale Forschung. Dabei ist SPECT ein leistungsfähiges Instrument zur Visualisierung spezifischer funktioneller Prozesse im Körper, wie z. B. der Herzmuskeldurchblutung oder des Knochenstoffwechsels. Typische Anwendungsbereiche an Labortieren sind die bildgebende Diagnostik im Rahmen von Studien oder die Entwicklung neuer Tracer für den klinischen Einsatz. Durch Innovationen wurden Auflösungen von bis zu einem Viertelmillimeter bei akzeptabler Empfindlichkeit erreichbar. Diese Fortschritte haben in letzter Zeit zu einem deutlich gestiegenen Interesse an SPECT sowohl im klinischen als auch im präklinischen Bereich geführt. Ziel dieser Arbeit war es, die Leistung des neuen U-SPECT5/CT E-Class von MILabs mit einem speziellen ultra-hochauflösenden Multi-Pinhole-Kollimator für Ratten und das Potenzial für die In-vivo-Bildgebung bei Ratten zu untersuchen. Dabei sind die Besonderheiten des U-SPECTs die großen stationären Detektoren und der neue iterative Rekonstruktionsalgorithmus. Außerdem verfügt die von uns verwendete „E-Klasse“ im Vergleich zum konventionellen System nur über zwei statt drei Detektoren. Zunächst wurden die Sensitivität, die maximale Ortsauflösung und die Homogenität als Leistungsparameter bestimmt. Anschließend wurde das Kontrast-Rausch-Verhältnis für verschiedene Aktivitätsniveaus, die mit denen typischer In-vivo-Studien vergleichbar sind, untersucht. Schließlich wurden zwei Beispielprotokolle für die Bildgebung mit 99mTc-MIBI und 99mTc-HMDP bei gesunden Ratten durchgeführt, um die In-vivo-Kapazitäten zu erfassen. Zur Bewertung wurden eine Kontrast-Rausch-Analyse und eine Bildqualitätsumfrage genutzt. Der Schwerpunkt lag dabei auf der Bildqualität in Abhängigkeit von der Scanzeit sowie dem Postrekonstruktionsfilters für ein breites Spektrum realistisch erreichbarer In-vivo-Bedingungen. Die Leistung war mit einer Sensitivität von 567 cps/MBq, einer maximalen Ortsauflösung von 1,20 mm und einer Homogenität von 55,5% mit anderen in der Literatur beschriebenen Systemen vergleichbar. Bei niedrigeren Aktivitäten verringerte sich die Auflösung in Phantomstudien auf ≥1,80 mm bei gleichbleibend guter Bildqualität. Es wurden hochqualitative Knochen- und Myokardperfusions-SPECTs mit einer Auflösung von ≥1,80 mm bzw. ≥2,20 mm bei Ratten erzielt. Obwohl die begrenzte Empfindlichkeit nach wie vor eine Schwäche der SPECT ist, kann das U-SPECT5/CT E-Class mit dem UHR-RM-Kollimator, trotz des fehlenden dritten Detektors, In-vivo-Ergebnisse auf höchstem Niveau erzielen. Es ist derzeit eine der besten Optionen für die hochauflösende Radionuklid-Bildgebung bei Ratten. KW - SPECT KW - Molekulare Bildgebung KW - Rodents KW - Image Quality KW - SPECT/CT Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-328608 ER - TY - THES A1 - Juhran, Nina T1 - Epidemiologie des Iodmangels im Würzburger Raum: Schilddrüsenvolumina und Iodausscheidung bei Schulkindern in Würzburg T1 - epidemiology of iodine deficiency in the area of wuerzburg: thyroid volume and ioduresis of children in wuerzburg N2 - Deutschland gilt bisher immer noch als Iodmangelgebiet, obwohl in der letzten Zeit einige Studien eine deutliche Verbesserung der Iodversorgung in der deutschen Bevölkerung zeigten. Allerdings wurde der Großteil dieser Untersuchungen nicht gemäß den epidemiologischen Kriterien der WHO, UNICEF und ICCIDD durchgeführt, was zu einem Selektionsbias im Hinblick auf die Einschätzung der Strumaprävalenz führte. Die ideale Zielgruppe für die Beurteilung der aktuellen Iodversorgung einer Population sind Kinder im Schulalter zwischen 7 und 17 Jahren, weil die kindliche Schilddrüse sehr viel empfindlicher auf Veränderungen in der Iodzufuhr reagiert, und Schulkinder leicht in großer Zahl repräsentativ untersucht werden können. Gleichzeitig werden dabei auch verschiedene soziale Bevölkerungsschichten abgedeckt. An der Würzburger Studie nahmen 591 Kinder teil. Dabei handelte es sich um 268 Mädchen und 323 Jungen im Alter von 7 bis 17 Jahren. Es wurden folgende Daten erhoben: Schilddrüsenvolumen mit Hilfe der Sonographie, Iodkonzentration im morgendlichem Mittelstrahlurin, Körpergewicht, Größe, Geschlecht und Alter. Der Median der Iodkonzentration im Urin lag bei 183 µg/L. Der Anteil an Urinproben mit Iodkonzentrationen unter 100µg/L bzw. unter 50µg/L betrug 15,4% (Ziel nach WHO: <50%) bzw. 4,3% (Ziel nach WHO: <20%). 17,3 % der Proben enthielten hohe Konzentrationen über 300µg/L. Damit sind alle Kriterien der WHO hinsichtlich einer ausreichenden Iodzufuhr erfüllt. Der Grund für diese deutliche Verbesserung ist zum einen darin zu sehen, daß fast alle Familien ( 97%) im Haushalt Iodsalz verwenden und 19,6% aller Kinder regelmäßig Iodtabletten einnehmen. Zum anderen basiert die mittlerweile normale Iodversorgung wohl hauptsächlich auf dem fast ausschließlichen Einsatz von Iodsalz in der Lebensmittelindustrie (Bäcker und Metzger). In Bezug auf die Referenzwerte der Schilddrüsenvolumina der WHO/ICCIDD ergab sich für die Würzburger Schulkinder eine Strumaprävalenz von 0,2%, sowohl in Relation zu Alter und Geschlecht, als auch zu Körperoberfläche und Geschlecht. Im Vergleich mit den 97. Perzentilen der ursprünglichen Normdaten von Gutekunst und Martin-Teichert errechnete sich wie statistisch zu erwarten war eine Kropfhäufigkeit von 3%. Damit sind die Schilddrüsenvolumina der Würzburger Schulkinder vergleichbar mit den aktuellen Werten von Kindern mit ausreichender Iodversorgung sowohl aus der Schweiz, als auch aus dem Raum Berlin und Leipzig. Deutschland ist deshalb wahrscheinlich nicht länger als ein Land mit einer Iodmangelsituation anzusehen, wenngleich diese Daten durch weitere flächendeckende Studien an Kindern untermauert werden müssen. Die Würzburger Untersuchung und die meisten der anderen aktuell veröffentlichten Studien an Schulkindern mit ausreichender Iodversorgung geben zudem Grund zur Annahme, daß die Referenzwerte der WHO/ICCIDD für die Schilddrüsenvolumina zu hoch angesetzt sind, was mittlerweile von Seiten der WHO korrigiert wird. N2 - Germany still is an area of iodine deficiency, although a lot of studies have shown that there is a significant improvement of the iodine supply. In this study we examined the thyroid volume and the ioduresis of children -according to the guidelines of the WHO- in the age of 7 to 18, because they show the current iodine supply. The results reveal that Wuerzburg is no longer an area of iodine deficieny, because the thyroid volumes of the children in Wuerzburg are smaller than postulated by the WHO and with a ioduresis of 183 µg/L iodine there is no longer a sign of iodine deficiency. KW - Würzburg KW - Schulkind KW - Iodmangel KW - Iod KW - Iodmangel KW - Schilddrüsenvolumen KW - iodine KW - iodine deficiency KW - thyroid volume Y1 - 2003 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-5643 ER - TY - THES A1 - Kaiser, Franz R. T1 - Ein \(^{18}\)F markiertes PET-Radiopharmakon (LMI1195) zur Bildgebung des Norepinephrin-Stoffwechsels im Rattenherz T1 - An \(^{18}\)-F labeled PET radiopharmaceutical (LMI1195) for imaging of the norepinephrine metabolism in the rat heart N2 - Der neuartige (18)F-markierte Tracer, LMI1195 (N-[3-bromo-4-(3-(18)F-fluoro-propoxy)-benzyl]-guanidine) wurde für die Bildgebung des sympathischen Nervensystems entwickelt; die hohe Spezifität dieses Tracers für den neuralen Uptake-1 Mechanismus wurde bereits gezeigt in Zell-Versuchen, sowie in Studien mit Kaninchen- und nicht menschlichen Primaten zur Bestimmung des kardialen Tracer-Uptakes. Das Ziel dieser Studie war es, die Mechanismen des kardialen (18)F-LMI1195-Uptakes in der Ratte zu untersuchen, von der bekannt ist, dass es neben dem Uptake-1 Mechanismus weitere Arten der Noradrenalin-Aufnahme im Herzen gibt. N2 - The novel PET Tracer N-[3-bromo-4-(3-18F-fluoropropoxy)-benzyl]-guanidin (LMI1195) has recently been developed for the imaging of the sympathetic nervous system. Previous studies in cell models, as well as rabbit and nonhuman primate studies have shown a high specificity for the cardiac neural uptake-1 mechanism. The aim of this study was to further assess the mechanisms of the cardiac 18-F-LMI1195 uptake in the rat heart, known to have additional, differing norepinephrine uptake mechanisms besides neural uptake-1. KW - LMI1195 KW - Uptake-1 KW - Ratte KW - LMI1195 KW - Uptake-1 KW - Ratte Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-244335 ER - TY - THES A1 - Kajdi, Georg Wilhelm T1 - iROLL - 3D-bildnavigierte, radioaktivitätsgestützte Resektion des nicht-palpablen Mammakarzinoms T1 - iROLL - image-radioguided occult lesion localization in breast cancer N2 - In dieser prospektiven Studie wurde die Durchführbarkeit der 3D-bildnavigierten, radioaktivitätsgestützten Resektion des nicht-palpablen Mammakarzinoms (iROLL) unter Verwendung der freehand SPECT (fhSPECT)-Technologie untersucht. Das Verfahren wurde mit der als Goldstandard etablierten, drahtgestützten Lokalisation (WGL) verglichen. Sekundäre Endpunkte der Studie waren die erfolgreiche Sentinellymphknotenbiopsie (SLNB) mittels fhSPECT, der Patientenkomfort beider Verfahren, die mögliche Vorhersage tumorpositiver Resektatränder mittels fhSPECT, inklusive notwendiger Nachresektionen und der Einfluss von iROLL auf die OP-Dauer. Die fhSPECT-gestützte iROLL ist ein schmerzarmes, patientenfreundliches, zeiteffizientes und v.a. gut durchführbares brusterhaltendes Therapieverfahren (BET) ist. Gegenüber der WGL wird eine einzeitige Markierung zur Primarius- und SLN-Markierung möglich, ohne dabei auf eine visuell fassbare, intraoperative Navigationshilfe verzichten zu müssen. N2 - In this prospective pilot study the feasability of iROLL (image-radioguided occult lesion localization in breast cancer)was investigated and compared to the gold standard of wire-guided localization (WGL). Secondary end-points were the sucessfull sentinel lymph node biopsy (SLNB) with the fhSPECT technology, evaluation of patient comfort and the possible prediction of tumor-positive resection margins with fhSPECT. Additional resections due to positive fhSPECT-scans and influence an operation time were also evaluated. fhSPECT-guided iROLL is a less painful, patient-friendly, time efficient and easily feasible therapy regimen for breast conserving surgery (BET). Compared to WGL it enables a one-time tracer-application for tumor and SLN detection while maintaining a visual component for intraoperative navigation. KW - Brustkrebs KW - Lymphknoten KW - Gammaspektrometer KW - iROLL KW - fhSPECT KW - 3D-Bildnavigation KW - Mammakarzinom KW - SLNB Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-180459 ER - TY - JOUR A1 - Kazuhino, Koshino A1 - Werner, Rudolf A. A1 - Toriumi, Fuijo A1 - Javadi, Mehrbod S. A1 - Pomper, Martin G. A1 - Solnes, Lilja B. A1 - Verde, Franco A1 - Higuchi, Takahiro A1 - Rowe, Steven P. T1 - Generative Adversarial Networks for the Creation of Realistic Artificial Brain Magnetic Resonance Images JF - Tomography N2 - Even as medical data sets become more publicly accessible, most are restricted to specific medical conditions. Thus, data collection for machine learning approaches remains challenging, and synthetic data augmentation, such as generative adversarial networks (GAN), may overcome this hurdle. In the present quality control study, deep convolutional GAN (DCGAN)-based human brain magnetic resonance (MR) images were validated by blinded radiologists. In total, 96 T1-weighted brain images from 30 healthy individuals and 33 patients with cerebrovascular accident were included. A training data set was generated from the T1-weighted images and DCGAN was applied to generate additional artificial brain images. The likelihood that images were DCGAN-created versus acquired was evaluated by 5 radiologists (2 neuroradiologists [NRs], vs 3 non-neuroradiologists [NNRs]) in a binary fashion to identify real vs created images. Images were selected randomly from the data set (variation of created images, 40%-60%). None of the investigated images was rated as unknown. Of the created images, the NRs rated 45% and 71% as real magnetic resonance imaging images (NNRs, 24%, 40%, and 44%). In contradistinction, 44% and 70% of the real images were rated as generated images by NRs (NNRs, 10%, 17%, and 27%). The accuracy for the NRs was 0.55 and 0.30 (NNRs, 0.83, 0.72, and 0.64). DCGAN-created brain MR images are similar enough to acquired MR images so as to be indistinguishable in some cases. Such an artificial intelligence algorithm may contribute to synthetic data augmentation for "data-hungry" technologies, such as supervised machine learning approaches, in various clinical applications. KW - AI KW - Magnetresonanztomografie KW - artificial intelligence KW - magnetic resonance imaging KW - MRI KW - DCGAN KW - GAN KW - stroke KW - machine learning Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-172185 VL - 4 IS - 4 ER - TY - THES A1 - Kemmer, Luisa Diana T1 - Darstellung von Inflammation in Atherosklerose mit dem CXCR4-gerichteten PET-Tracer \(^{68}\)Ga-Pentixafor im Vergleich zur \(^{18}\)F-FDG-PET/CT T1 - Imaging inflammation in atherosclerosis with the CXCR4-targeted PET tracer \(^{68}\)Ga-Pentixafor compared to \(^{18}\)F-FDG-PET/CT N2 - Herz-Kreislauf-Erkrankungen zählen zu den häufigsten Todesursachen weltweit. Ein ihr zugrundeliegender pathologischer Prozess ist die Atherosklerose. Die Ruptur eines atheroskelrotischen Plaques kann lebensbedrohlich sein. Derzeit existieren weder ein evaluierter Biomarker noch eine Bildgebungstechnik, die das Risiko einer solchen Plaqueruptur und eines nachfolgenden akuten kardiovaskulären Ereignisses vorhersagen können. Um die bildgebenden Verfahren zur Detektion der Atherosklerose zu optimieren, wurde in dieser Dissertationsarbeit untersucht, ob der PET/CT-Tracer 68Ga-Pentixafor im Vergleich zu 18F-FDG bessere Ergebnisse in der Diagnostik der Atherosklerose erzielen kann. Insgesamt wurden 144 onkologische Patienten in die Studie einbezogen, bei denen die 18F-FDG-PET/CT sowie 68Ga-Pentifaxor-PET/CT aus klinischen Gründen indiziert waren. Befunde, bei denen eine gegenüber dem Hintergrund vermehrte Speicherung ohne physiologische Erklärung nachgewiesen werden konnte, wurden als positiv bewertet. Um Unterschiede zwischen den Patienten außer Acht lassen zu können, wurde die target-to-background-ratio (TBR) berechnet. Zur Beschreibung der Speicherintensität einer Läsion wurde der standardized uptake value (SUV) bestimmt. Nach Auswertung der Daten zeigte sich eine mäßige Korrelation der Anzahl von 68Ga-Pentixafor-positiven Läsionen mit der Anzahl der 18F-FDG positiven Läsionen. Die CXCR4-gerichtete Bildgebung mit 68Ga-Pentixafor identifizierte mehr Läsionen als die 18F-FDG-PET/CT. Bezüglich ihres Verteilungsmusters wiesen die beiden Tracer eine geringe Korrelation auf. Die Aufnahmeintensität beider Tracer korrelierte umgekehrt mit dem Ausmaß der Verkalkung. Stark verkalkte Plaques zeigten die niedrigste Traceraufnahme für beide PET-Tracer. Weitere Studien zur Aufklärung der zugrunde liegenden biologischen Mechanismen und Quellen der CXCR4-Positivität sind in hohem Maße gerechtfertigt. N2 - Cardiovascular diseases are among the most common causes of death worldwide. A pathological process underlying these diseases is atherosclerosis. The rupture of an atherosclerotic plaque can be life-threatening. Currently, there is neither an evaluated biomarker nor an imaging technique that can predict the risk of such a plaque rupture and subsequent acute cardiovascular event. To optimize imaging methods for the detection of atherosclerosis, this dissertation investigated whether the PET/CT tracer 68Ga-Pentixafor can achieve better diagnostic results for atherosclerosis compared to 18F-FDG. A total of 144 oncological patients were included in the study, for whom 18F-FDG-PET/CT and 68Ga-Pentixafor-PET/CT were clinically indicated. Lesions showing increased uptake compared to the background without physiological explanation were rated as positive. To disregard differences between patients, the target-to-background ratio (TBR) was calculated. To describe the uptake intensity of a lesion, the standardized uptake value (SUV) was determined. After evaluating the data, a moderate correlation was observed between the number of 68Ga-Pentixafor-positive lesions and the number of 18F-FDG-positive lesions. CXCR4-targeted imaging with 68Ga-Pentixafor identified more lesions than 18F-FDG-PET/CT. Regarding their distribution patterns, the two tracers showed a low correlation. The uptake intensity of both tracers inversely correlated with the extent of calcification. Highly calcified plaques exhibited the lowest tracer uptake for both PET tracers. Further studies to elucidate the underlying biological mechanisms and sources of CXCR4 positivity are highly warranted. KW - Arteriosklerose KW - Positronen-Emissions-Tomografie KW - Chemokinrezpetor KW - CXCR4 KW - \(^{68}\)Ga-Pentixafor KW - \(^{18}\)F-FDG Y1 - 2024 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-360013 ER - TY - JOUR A1 - Khatri, Wajahat A1 - Chung, Hyun Woo A1 - Werner, Rudolf A. A1 - Leal, Jeffrey P. A1 - Pienta, Kenneth J. A1 - Lodge, Martin A. A1 - Gorin, Michael A. A1 - Pomper, Martin G. A1 - Rowe, Steven P. T1 - Effect of point-spread function reconstruction for indeterminate PSMA-RADS-3A lesions on PSMA-targeted PET imaging of men with prostate cancer JF - Diagnostics N2 - Purpose: Prostate-specific membrane antigen (PSMA) positron emission tomography (PET) is emerging as an important modality for imaging patients with prostate cancer (PCa). As with any imaging modality, indeterminate findings will arise. The PSMA reporting and data system (PSMA-RADS) version 1.0 codifies indeterminate soft tissue findings with the PSMA-RADS-3A moniker. We investigated the role of point-spread function (PSF) reconstructions on categorization of PSMA-RADS-3A lesions. Methods: This was a post hoc analysis of an institutional review board approved prospective trial. Around 60 min after the administration of 333 MBq (9 mCi) of PSMA-targeted \(^{18}\)F-DCFPyL, patients underwent PET/computed tomography (CT) acquisitions from the mid-thighs to the skull vertex. The PET data were reconstructed with and without PSF. Scans were categorized according to PSMA-RADS version 1.0, and all PSMA-RADS-3A lesions on non-PSF images were re-evaluated to determine if any could be re-categorized as PSMA-RADS-4. The maximum standardized uptake values (SUVs) of the lesions, mean SUVs of blood pool, and the ratios of those values were determined. Results: A total of 171 PSMA-RADS-3A lesions were identified in 30 patients for whom both PSF reconstructions and cross-sectional imaging follow-up were available. A total of 13/171 (7.6%) were re-categorized as PSMA-RADS-4 lesions with PSF reconstructions. A total of 112/171 (65.5%) were found on follow-up to be true positive for PCa, with all 13 of the re-categorized lesions being true positive on follow-up. The lesions that were re-categorized trended towards having higher SUV\(_{max}\)-lesion and SUV\(_{max}\)-lesion/SUV\(_{mean}\)-blood-pool metrics, although these relationships were not statistically significant. Conclusions: The use of PSF reconstructions for \(^{18}\)F-DCFPyL PET can allow the appropriate re-categorization of a small number of indeterminate PSMA-RADS-3A soft tissue lesions as more definitive PSMA-RADS-4 lesions. The routine use of PSF reconstructions for PSMA-targeted PET may be of value at those sites that utilize this technology. KW - prostate-specific membrane antigen KW - reporting and data system KW - positron emission tomography Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-236528 SN - 2075-4418 VL - 11 IS - 4 ER - TY - THES A1 - Kirchgäßner, Christoph T1 - Bestimmung von Referenzbereichen für die Schilddrüsenhormonparameter TSH, fT3 und fT4 bei Neugeborenen, Kindern und Jugendlichen T1 - Reference values of thyroid hormones TSH, fT3 and fT4 for newborns, children and teenagers N2 - Neubestimmung der Referenzbereiche für die Schilddrüsenhormonparameter TSH, fT3 und fT4 für Kinder von der Geburt bis zum 18. Lebensjahr mittels Immulite Immunoassay. N2 - Creation of new reference values for thyroid hormones TSH, fT3 and fT4 for children using the Immulite immunoassay KW - Schilddrüse KW - Thyreotropin KW - Thyroxin KW - Normalwert KW - fT3 KW - fT4 KW - Immulite KW - Immunoassay KW - Referenzbereiche KW - reference values KW - thyroid KW - TSH KW - fT3 KW - fT4 Y1 - 2010 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-54090 ER - TY - THES A1 - Kleinert, Kathrin T1 - Einfluss der thyreostatischen Therapie auf den Erfolg einer Radioiod-Ersttherapie bei der Autoimmunthyreopathie vom Typ M. Basedow T1 - Antithyroid drugs as a factor influencing the outcome of radioiodine therapy in Graves`disease N2 - Ziel vorliegender Studie war die Einflussfaktoren der Radioiodtherapie bei der Autoimmunthyreopathie vom Typ M. Basedow insbesondere im Hinblick auf die prätherapeutische thyreostatische Therapie aufgrund der unklaren Datenlage zu erfassen. Der Einfluss von Geschlecht, Alter, Schilddrüsenvolumen, applizierter Aktivität, erzielter Dosis, Uptake und verschiedener Laborparameter, wie TSH, fT3, fT4 wurde untersucht. Aus einem Kollektiv von 465 Patienten konnten 283 als Ersttherapierte identifiziert werden und weitern uni-und multivariater Analyse unterzogen werden. Als Therapieerfolg definiertn wir Patienten, deren TSH- Spiegel ohne Medikation im Normbereich lag, als auch jene, die unabhängig vom TSH-Spiegel nach Radioiodidtherapie eine hypothyreote Stoffwechsellage aufwiesen und substituiert werden mussten. Die Erfolgsquote betrug 86,6%. Unsere Ergebnisse der univariaten Analyse erlauben den Schluss, dass sowohl die erzielte Dosis, das Schilddrüsenvolumen, die applizierte Aktivität, sowie der Uptake relevante Einflussfaktoren einer Radioiodtherapie sind. Die simultane thyreostatische Therapie zeigte weder in uni- noch multivariater Analyse signifikante Unterschiede bezüglich einer erfolgreichen Radioiodtherapie. Eine um 5% niedrigere Erfolgsrate unter simultaner Thyreostase, sowie die Ergebnisse multivariater Betrachtungen deuten jedoch auf einen tendentiellen Einfluss hin. Als Konsequenz für die routinemässige Durchführung einer Radioiodtherapie erscheint es sinnvoll, in Einzelfällen die thyreostatische Medikation frühzeitig vor einer Radioiodtherapie abzusetzen. Eine Beurteilung hinsichtlich des Langzeiterfolges sollte frühestens nach 1 Jahr erfolgen. N2 - There is a controversy over the factors that may influence the outcome of radioiodine therapy in Graves` disease. Antithyroid medication has been claimed to negatively influence the effectiveness of radioiodine therapy in Graves` disease. In a longitudinal study we assessed the influence of sex, age, antithyroid drugs, target mass, uptake, target radiation dose, applied activity, delivered dose, TSH, fT3, fT4 levels on the outcome of radioiodine therapy. 283 patients (237 female, 46 male) suffering from Graves` disease were entered in the study and followed up until 24 months after therapy. Treatment was defined successful when the TSH level was found to be normal or elevated. 245 patients were successfully treated. Univariate analysis showed the factors target mass, applied activity and delivered dose influencing the outcome of radioiodine therapy. Forward stepwise multiple regression analysis models retained only the delivered dose and the target mass as significantly associated with the outcome of therapy. Antithyroid medication showed a tendency in influencing the result but no significant result. Whereas concomitant antithyroid medication had no significant influence in Graves` disease. This factor only showed a tendency. Conclusion of this longitudinal study was an interruption of concomitant antithyroid medication before a radioiodine therapy can be agreed and the total result can be predicted only one year after radioiodine therapy. KW - Radioiodtherapie KW - M. Basedow KW - Autoimmunthyreopathie KW - thyreostatischen Therapie KW - radioiodine therapy KW - Graves´ disease KW - antithyroid therapy Y1 - 2004 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-11759 ER - TY - JOUR A1 - Kläsner, Benjamin A1 - Buchmann, Niels A1 - Gempt, Jens A1 - Ringel, Florian A1 - Lapa, Constantin A1 - Krause, Bernd Joachim T1 - Early [\(^{18}\)F]FET-PET in Gliomas after Surgical Resection: Comparison with MRI and Histopathology JF - PLoS One N2 - Background The precise definition of the post-operative resection status in high-grade gliomas (HGG) is crucial for further management. We aimed to assess the feasibility of assessment of the resection status with early post-operative positron emission tomography (PET) using [\(^{18}\)F]O-(2-[\(^{18}\)F]-fluoroethyl)-L-tyrosine ([\(^{18}\)F]FET). Methods 25 patients with the suspicion of primary HGG were enrolled. All patients underwent preoperative [\(^{18}\)F]FET-PET and magnetic resonance imaging (MRI). Intra-operatively, resection status was assessed using 5-aminolevulinic acid (5-ALA). Imaging was repeated within 72h after neurosurgery. Post-operative [\(^{18}\)F]FET-PET was compared with MRI, intra-operative assessment and clinical follow-up. Results [\(^{18}\)F]FET-PET, MRI and intra-operative assessment consistently revealed complete resection in 12/25 (48%) patients and incomplete resection in 6/25 cases (24%). In 7 patients, PET revealed discordant findings. One patient was re-resected. 3/7 experienced tumor recurrence, 3/7 died shortly after brain surgery. Conclusion Early assessment of the resection status in HGG with [\(^{18}\)F]FET-PET seems to be feasible. KW - glioblastoma multiforme KW - brain tumors KW - C-11-methionine pet KW - positron-emission-tomography KW - improves KW - survival KW - delineation KW - radiotherapy KW - methionine pet KW - cerebral gliomas Y1 - 2015 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-139549 VL - 10 IS - 10 ER - TY - JOUR A1 - Konijnenberg, Mark A1 - Herrmann, Ken A1 - Kobe, Carsten A1 - Verburg, Frederik A1 - Hindorf, Cecilia A1 - Hustinx, Roland A1 - Lassmann, Michael T1 - EANM position paper on article 56 of the Council Directive 2013/59/Euratom (basic safety standards) for nuclear medicine therapy JF - European Journal of Nuclear Medicine and Molecular Imaging N2 - The EC Directive 2013/59/Euratom states in article 56 that exposures of target volumes in nuclear medicine treatments shall be individually planned and their delivery appropriately verified. The Directive also mentions that medical physics experts should always be appropriately involved in those treatments. Although it is obvious that, in nuclear medicine practice, every nuclear medicine physician and physicist should follow national rules and legislation, the EANM considered it necessary to provide guidance on how to interpret the Directive statements for nuclear medicine treatments. For this purpose, the EANM proposes to distinguish three levels in compliance to the optimization principle in the directive, inspired by the indication of levels in prescribing, recording and reporting of absorbed doses after radiotherapy defined by the International Commission on Radiation Units and Measurements (ICRU): Most nuclear medicine treatments currently applied in Europe are standardized. The minimum requirement for those treatments is ICRU level 1 (“activity-based prescription and patient-averaged dosimetry”), which is defined by administering the activity within 10% of the intended activity, typically according to the package insert or to the respective EANM guidelines, followed by verification of the therapy delivery, if applicable. Non-standardized treatments are essentially those in developmental phase or approved radiopharmaceuticals being used off-label with significantly (> 25% more than in the label) higher activities. These treatments should comply with ICRU level 2 (“activity-based prescription and patient-specific dosimetry”), which implies recording and reporting of the absorbed dose to organs at risk and optionally the absorbed dose to treatment regions. The EANM strongly encourages to foster research that eventually leads to treatment planning according to ICRU level 3 (“dosimetry-guided patient-specific prescription and verification”), whenever possible and relevant. Evidence for superiority of therapy prescription on basis of patient-specific dosimetry has not been obtained. However, the authors believe that a better understanding of therapy dosimetry, i.e. how much and where the energy is delivered, and radiobiology, i.e. radiation-related processes in tissues, are keys to the long-term improvement of our treatments. KW - nuclear medicine therapy KW - dosimetry KW - optimization KW - BSS directive Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-235280 SN - 1619-7070 VL - 48 ER - TY - JOUR A1 - Kosmala, Aleksander A1 - Serfling, Sebastian E. A1 - Dreher, Niklas A1 - Lindner, Thomas A1 - Schirbel, Andreas A1 - Lapa, Constantin A1 - Higuchi, Takahiro A1 - Buck, Andreas K. A1 - Weich, Alexander A1 - Werner, Rudolf A. T1 - Associations between normal organs and tumor burden in patients imaged with fibroblast activation protein inhibitor-directed positron emission tomography JF - Cancers N2 - (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. KW - PET KW - [\(^{68}\)Ga]Ga-FAPI KW - theranostics KW - radioligand therapy KW - fibroblast activation protein Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-275154 SN - 2072-6694 VL - 14 IS - 11 ER - TY - THES A1 - Kranzfelder, Michael T1 - Orale versus intravenöse Radioiodtherapie bei Unifokaler Autonomie und Morbus Basedow T1 - Oral vs. intravenous radioiodine therapy in unifocal autonomy and Graves' disease N2 - Im Rahmen der dieser Arbeit zugrunde liegenden prospektiven, randomisierten Studie wurden im Zeitraum Juli 2001 bis August 2002 insgesamt 120 Patienten der Klinik und Poliklinik für Nuklearmedizin der Universität Würzburg mit den Diagnosen Unifokale Autonomie (UFA) und Morbus Basedow (MB) mit einer RIT behandelt. Die therapeutische Applikation des 131- I erfolgte in jeder der Diagnosegruppen entweder oral in Kapsel-, oder intravenös in flüssiger Form. Ziel dieser Arbeit war es, den Einflussgrad der Applikationsmodalität des Radionuklids, d.h. orale (Kapsel) versus intravenöse (flüssige) Verabreichung des 131- I, hinsichtlich des Therapieergebnisses zu untersuchen. Ein halbes Jahr nach der RIT zeigten in der Erkrankungsgruppe UFA 94 % der Patienten bei der oralen Applikationsform und 81 % der Patienten bei der intravenösen Applikationsform einen Behandlungserfolg. In der Diagnosegruppe MB waren im gleichen Zeitraum 67 % der Studienteilnehmer bei der oralen Applikationsform und 65 % der Studienteilnehmer bei der intravenösen Applikationsform erfolgreich therapiert. Zwischen beiden Applikationsformen wurden bei UFA und MB keine signifikanten Unterschiede hinsichtlich des Therapieergebnisses gefunden. Das Ergebnis bietet somit keinen Anhalt dafür, dass bei der oralen Applikationsform enterale Absorptionsverluste von Radioiod auftreten. Ohne eine Verschlechterung des Behandlungserfolges zu befürchten, kann die Verabreichungsmodalität des Radionuklids daher individuell getroffen werden. Aus Handhabungsgründen und wegen des Strahlenschutzes des Personals wird man aber in der Regel die Kapsel bevorzugen. N2 - In a prospective randomised study, we investigated the influence of the route of administration (oral vs. intravenous) of radioiodide on therapy outcome. 60 patients suffering from Graves disease (GD) and 60 patients with unifocal autonomy (UA) participated in the study and were randomly treated with either orally or intravenously administered radioiodide. No improvement in accuracy of dosimetry was achieved when radioiodide was administered intravenously. Mean therapeutic doses were identical following intravenous or oral administration. No differences according to treatment modality were found with regard to therapeutic outcome. In the UA group, successful treatment, defined as a normal or elevated TSH level, was observed in 94% of patients after oral administration and in 81% after intravenous administration; corresponding figures in the GD group were 67% and 65%. KW - Radioiodtherapie KW - Oral KW - Intravenös KW - Unifokale Autonomie KW - Morbus Basedow KW - Radioiodine therapy KW - Oral KW - Intravenous KW - Unifocal autonomy KW - Graves' disease Y1 - 2005 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-14383 ER - TY - THES A1 - Kreißl, Michael T1 - Vergleich der Wirksamkeit zweier verschieden dosierter Levothyroxin-Iodid-Kombinationen in der Therapie der euthyreoten diffusen Struma T1 - Comparison of the efficacy of two differently dosed levothyroxine-iodide-combinations in the treatment of euthyroid diffuse goiter N2 - Grundproblematik und Fragestellung: In der Behandlung der endemischen Struma läßt sich durch Levothyroxin und/oder Iodid eine Reduktion des Schilddrüsenvolumens erreichen. Eine unter Levothyroxintherapie auftretende TSH-Suppression kann sich jedoch über die Persistenz des intrathyreoidalen Iodmangels negativ auf die Rezidivhäufigkeit auswirken. In dieser Studie soll die Wirksamkeit zweier verschieden dosierter Kombinationspräparate aus Levothyroxin und Iodid verglichen werden, unter besonderer Berücksichtigung der Auswirkung des Levothyroxinanteils auf die intrathyreoidale Iodkonzentration. Patienten und Methodik: 44 Patientinnen mit euthyreoter diffuser Struma wurden in die Studie aufgenommen und randomisiert zwei Therapiegruppen zugeordnet. Gruppe A wurde mit 75 µg Levothyroxin und 150 µg Iodid (Verhältnis 1:2) behandelt. Gruppe B erhielt eine Kombination aus 100 µg Levothyroxin und 100 µg Iodid (Verhältnis 1:1) Die Therapie erstreckte sich über drei Monate mit anschließendem Beobachtungsintervall von drei Monaten ohne Medikation. Zu Studienbeginn, nach drei und sechs Monaten erfolgte eine Messung der intrathyreoidalen Iodkonzentration mittels Röntgenfluoreszenzanalyse, des sonografischen Schilddrüsenvolumens, der Iodausscheidung im Spontanurin und des basalen TSH, sowie der Schilddrüsenhormone und des Thyreoglobulins. Die Verträglichkeit der Präparate wurde ebenfalls erfaßt. Ergebnisse: Im Verlauf der Studie, sowohl unter Therapie, als auch während der Nachbeobachtungsphase kam es in beiden Gruppen (auswertbar in Gruppe B n = 20, in Gruppe A n = 21) nur zu geringen, nicht signifikanten Veränderungen des intrathyreoidalen Iodgehalts. Durch die Behandlung reduzierte sich das Schilddrüsenvolumen in Gruppe B um im Mittel 17,3% gegenüber dem Ausgangswert (p<0,001); in Gruppe A um 14,8% (p<0,001). Der erreichte Effekt blieb in Gruppe B über die Nachbeobachtungsperiode erhalten, in Gruppe A sank das mittlere Volumen um weitere vier Prozent (n.s.). Ein signifikanter Unterschied zwischen den Gruppen ließ sich für die intrathyreoidale Iodkonzentration, wie auch für das Schilddrüsenvolumen nicht nachweisen. In Gruppe B war eine statistisch signifikant stärkere TSH-Suppression (p=0,04) und ein höherer TSH-Anstieg (p=0,025) nach Therapie im Vergleich zu Gruppe A zu beobachten. Folgerung: Beide Kombinationspräparate bewirkten eine vergleichbare dauerhafte Volumenreduktion der Schilddrüse ohne relevante Veränderung der intrathyreoidalen Iodkonzentration. Aufgrund des geringeren posttherapeutischen TSH-Anstiegs scheint die 1:2 Kombination gegenüber der 1:1 Kombination geringe Vorteile zu bieten. N2 - Basic problem and objective: A reduction of thyroid volume may be achieved by treatment with levothyroxine and/or iodide. TSH-suppression which may be caused by levothyroxine monotherapy is considered to lead to persisting intrathyroidal iodine deficiency and frequent relapses. Aim of this study was to compare the efficacy of two differently dosed preparations containing both levothyroxine and iodide especially considering the influence of the levothyroxine on intrathyroidal iodine concentration. Patients and methods: 44 female patients with euthyroid diffuse goiters were included into the study and randomly assigned to two groups. Group A was treated with 75 µg of levothyroxine and 150 µg of iodide (relation 1:2). Group B received a combination of 100 µg of levothyroxine and 100 µg of iodide (relation 1:1).Therapy was carried out for three months with a follow up period without any medication of another three months. Patients were examined before entering the study, after three months of treatment and after six months following the wash out period. The examination consisted of a measurement of thyroidal iodine concentration by X-ray fluorescence analysis, thyroidal volume by ultrasound, iodine excretion and TSH. Thyroidal hormones, thyroglobulin and side effects were also monitored. Results: Throughout the study only small non significant changes of intrathyroidal iodine concentration and no group differences were observed. In group A (21 patients) only 14.8% (p<0.001) was reached, in group B (20 patients) treatment lead to a mean reduction of thyroidal volume of 17.3% (p<0.001). During the follow up period thyroids in group B kept their size whereas the mean volume decreased 4 percent (n.s) in group A. This difference was not significant. Group B showed a statistically relevant stronger TSH suppression (p=0.04) and a more pronounced rise of TSH after therapy (p=0.025) than A. Conclusion: Both preparations were equally efficacious in terms of thyroid volume reduction without reducing thyroidal iodine concentration. Being both effective in the treatment of endemic goiter the 2:1 combination seems to be slightly more favorable because of the lower posttherapeutic rise of TSH. KW - Struma KW - euthyreote KW - Therapie KW - Jodid KW - Levothyroxin KW - goiter KW - endemic KW - therapy KW - iodine KW - levothyroxine Y1 - 2003 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-6106 ER - TY - JOUR A1 - Kunzmann, Volker A1 - Herrmann, Ken A1 - Bluemel, Christina A1 - Kapp, Markus A1 - Hartlapp, Ingo A1 - Steger, Ulrich T1 - Intensified neoadjuvant chemotherapy with nab-paclitaxel plus gemcitabine followed by FOLFIRINOX in a patient with locally advanced unresectable pancreatic cancer JF - Case Reports in Oncology N2 - The prognosis of patients with locally advanced pancreatic cancer can be improved if secondary complete (R0) resection is possible. In patients initially staged as unresectable this may be achieved with neoadjuvant treatment which is usually chemoradiotherapy based. We report the case of a 46-year-old patient with an unresectable, locally advanced pancreatic cancer (pT4 Nx cM0 G2) who was treated with a sequential neoadjuvant chemotherapy regimen consisting of 2 cycles of nab-paclitaxel plus gemcitabine followed by 4 cycles of FOLFIRINOX. Neoadjuvant chemotherapy resulted in secondary resectability (R0 resection). After 2 cycles of nab-paclitaxel plus gemcitabine, the patient already had a complete metabolic remission as measured by integrated fludeoxyglucose ((18)F) positron emission tomography and computerized tomography. After a follow-up of 18 months the patient is alive without progression of disease. We propose to assess the clinical benefit of sequencing the combinations nab-paclitaxel plus gemcitabine and FOLFIRINOX as neoadjuvant therapy for patients with locally advanced and initially unresectable pancreatic cancer in a controlled clinical trial. KW - nab-paclitaxel KW - neoadjuvant chemotherapy KW - oxaliplatin KW - pancreatic cancer KW - locally advanced disease KW - irinotecan KW - gemcitabine KW - folinic acid KW - 5-Fluorouracil Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-120189 SN - 1662-6575 VL - 7 IS - 3 ER - TY - THES A1 - Künzig, Teresa T1 - Veränderungen im Schilddrüsenhormonmetabolismus während thyreosuppressiver Levothyroxintherapie bei Patienten mit differenziertem Schilddrüsenkarzinom T1 - Changes within the thyroid hormone matabolism during suppressive LT4 therapy in patients with differentiated thyroid cancer N2 - Ziel der Arbeit: Der Einfluss langfristiger thyreosuppressiver Levothyroxintherapie auf den Schilddrüsenhormonmetabolismus bei Patienten mit differenziertem Schilddrüsenkarzinom ist bisher unbekannt. Ziel dieser Arbeit war es herauszufinden, ob und welche Änderungen der Schilddrüsenhormonparameter nach langfristiger LT4-Einnahme auftreten. Anhand der zweiten Studie sollte ermittelt werden, ob diese Veränderungen plötzlich und sprunghaft auftreten oder ob es sich dabei um einen kontinuierlichen Prozess handelt. Patienten, Material, Methoden: Das Kollektiv der ersten Studie bestand aus 61 Patienten mit differenziertem Schilddrüsenkarzinom. Für jeden dieser Patienten wurden eingefrorene Seren von zwei verschiedenen Zeitpunkten ausgewählt: Zeitpunkt 1 (entnommen in-nerhalb des ersten Jahres nach I-131-Ablation; TSH-Wert < 0,3 mlU/l; Rekrutie-rungszeitraum 1999-2002) und Zeitpunkt 2 (letzte verfügbare Probe mit TSH-Wert < 0,3 mIU/l; mindestens drei Jahre lang protokollierte, ununterbrochene LT4-Therapie; Rekrutierungszeitraum 2005-2009). Die Hormonspiegel von TSH, reversem T3, TT3 und TT4 und weiterer Parameter wurden zum Zeitpunkt 1 und Zeitpunkt 2 gemessen und die Beziehung dieser Parameter zueinander wurde analysiert. In der zweiten Studie bildeten 24 Patienten mit differenziertem Schilddrüsen-karzinom das Patientenkollektiv. Auch hier wurden gefroren gelagerte Blutpro-ben nach bestimmten Kriterien ausgewählt und untersucht. Eingeschlossen wurden Patienten, von denen mindesten drei Seren im Anschluss an die letzte Hypothyreose vorhanden waren, die unter thyreosuppressiver Therapie ent-nommen wurden, so dass eine serielle Messung durchgeführt werden konnte. Der Zeitraum zwischen Hypothyreose und nachfolgendem Entnahmezeitpunkt des ersten folgenden Serums dufte höchsten neun Monate betragen. Die mediane Anzahl der vorhandenen Proben lag bei sechs, die mediane vergangene Zeit nach letzter Hypothyreose betrug 1,17 Jahre. Es wurde der zeitliche Verlauf der bestimmten Hormonparameter analysiert. Ergebnisse: Die Ergebnisse der ersten Studie zeigten signifikant erniedrigte TT3-, TT4- und TSH-Spiegel zum Zeitpunkt 2 (P < 0,001), während LT4-Dosis, Körpergewicht und rT3-Spiegel zwischen Zeitpunkt 1 und Zeitpunkt 2 konstant blieben. Es zeigten sich keine signifikanten Veränderungen in dem Verhältnis der LT4-Dosis pro kg Körpergewicht zu den fT4-Spiegeln (P = 0,83). Das Verhältnis von TT4 zu TT3 war zum Zeitpunkt 2 erhöht (P < 0,001), während das Verhältnis von TT4 zu rT3 und das Verhältnis von TT3 zu rT3 zum Zeitpunkt 2 signifikant erniedrigt waren. Im kurzen Beobachtungszeitraum der zweiten Studie zeigten sich innerhalb der ersten 1,35 Jahre, in denen der durchschnittliche Entnahmezeitpunkt der Proben lag, keine wesentlichen Veränderungen bezüglich der LT4-Dosis pro kg Körpergewicht, der fT4-Spiegel, der rT3 Spiegel, des Verhältnisses von TT4 zu rT3 oder des Verhältnisses von TT4 zu TT3. Fazit: Es lässt sich schlussfolgern, dass nach langfristiger TSH-suppressiver Levothyroxintherapie bei Patienten mit differenziertem Schilddrüsenkarzinom signifikante Veränderungen im Schilddrüsenhormonmetabolismus auftreten, die am besten durch eine kombinierte Herunterregulierung der Typ-I-und der Typ-II-Deiodinase und einer Hochregulierung der Typ-III-Deiodinase zu erklären sind. Diese Veränderungen treten nicht plötzlich und sprunghaft auf sondern ereignen sich eher in einem kontinuierlichen Prozess über viele Jahre hinweg. N2 - After long-term suppressive LT4 therapy significant changes in the thyroid hormone matabolism appeared, which are best explained by a combined deiodinase subtype 2 (D2)/deiodinase subtype 3 (D3) downregulation and deiodinase subtype 3 (D3) upregulation. These changes do not seem to happen suddenly or rapid but occur in a continuous process over many years KW - Schilddrüsenhormonmetabolismus Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-118504 ER - TY - JOUR A1 - Lambertini, Alessandro A1 - Hartrampf, Philipp E. A1 - Higuchi, Takahiro A1 - Serfling, Sebastian E. A1 - Meybohm, Patrick A1 - Schirbel, Andreas A1 - Buck, Andreas K. A1 - Werner, Rudolf A. T1 - CXCR4-targeted molecular imaging after severe SARS-Cov-2 infection JF - European Journal of Nuclear Medicine and Molecular Imaging N2 - No abstract available. KW - CXCR4-targeting KW - SARS-CoV-2 KW - COVID-19 KW - molecular imaging Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-324619 VL - 50 IS - 1 ER - TY - JOUR A1 - Lapa, Constantin A1 - Arias-Loza, Paula A1 - Hayakawa, Nobuyuki A1 - Wakabayashi, Hiroshi A1 - Werner, Rudolf A. A1 - Chen, Xinyu A1 - Shinaji, Tetsuya A1 - Herrmann, Ken A1 - Pelzer, Theo A1 - Higuchi, Takahiro T1 - Whitening and impaired glucose utilization of brown adipose tissue in a rat model of type 2 diabetes mellitus JF - Scientific Reports N2 - 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. KW - molecular medicine KW - endocrinology Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-159066 VL - 7 ER - TY - JOUR A1 - Lapa, Constantin A1 - Garcia-Velloso, Maria J. A1 - Lückerath, Katharina A1 - Samnick, Samuel A1 - Schreder, Martin A1 - Otero, Paula Rodriguez A1 - Schmid, Jan-Stefan A1 - Herrmann, Ken A1 - Knop, Stefan A1 - Buck, Andreas K. A1 - Einsele, Hermann A1 - San-Miguel, Jesus A1 - Kortüm, Klaus Martin T1 - \(^{11}\)C-methionine-PET in multiple myeloma: a combined study from two different institutions JF - Theranostics N2 - \(^{11}\)C-methionine (MET) has recently emerged as an accurate marker of tumor burden and disease activity in patients with multiple myeloma (MM). This dual-center study aimed at further corroboration of the superiority of MET as positron emission tomography (PET) tracer for staging and re-staging MM, as compared to \(^{18}\)F-2`-deoxy-2`-fluoro-D-glucose (FDG). 78 patients with a history of solitary plasmacytoma (n=4), smoldering MM (SMM, n=5), and symptomatic MM (n=69) underwent both MET- and FDG-PET/computed tomography (CT) at the University Centers of Würzburg, Germany and Navarra, Spain. Scans were compared on a patient and on a lesion basis. Inter-reader agreement was also evaluated. In 2 patients, tumor biopsies for verification of discordant imaging results were available. MET-PET detected focal lesions (FL) in 59/78 subjects (75.6%), whereas FDG-PET/CT showed lesions in only 47 patients (60.3%; p<0.01), accordingly disease activity would have been missed in 12 patients. Directed biopsies of discordant results confirmed MET-PET/CT results in both cases. MET depicted more FL in 44 patients (56.4%; p<0.01), whereas in two patients (2/78), FDG proved superior. In the remainder (41.0%, 32/78), both tracers yielded comparable results. Inter-reader agreement for MET was higher than for FDG (κ = 0.82 vs κ = 0.72). This study demonstrates higher sensitivity of MET in comparison to standard FDG to detect intra- and extramedullary MM including histologic evidence of FDG-negative, viable disease exclusively detectable by MET-PET/CT. MET holds the potential to replace FDG as functional imaging standard for staging and re-staging of MM. KW - medicine KW - PET/CT KW - \(^{11}\)C-methionine KW - multiple myeloma KW - FDG Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-172038 VL - 7 IS - 11 ER - TY - JOUR A1 - Lapa, Constantin A1 - Herrmann, Ken A1 - Schirbel, Andreas A1 - Hänscheid, Heribert A1 - Lückerath, Katharina A1 - Schottelius, Margret A1 - Kircher, Malte A1 - Werner, Rudolf A. A1 - Schreder, Martin A1 - Samnick, Samuel A1 - Kropf, Saskia A1 - Knop, Stefan A1 - Buck, Andreas K. A1 - Einsele, Hermann A1 - Wester, Hans-Juergen A1 - Kortüm, K. Martin T1 - CXCR4-directed endoradiotherapy induces high response rates in extramedullary relapsed multiple myeloma JF - Theranostics N2 - 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. KW - medicine KW - multiple myeloma KW - PET KW - CXCR4 KW - theranostics Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-172095 VL - 7 IS - 6 ER - TY - JOUR A1 - Lapa, Constantin A1 - Kircher, Malte A1 - Hänscheid, Heribert A1 - Schirbel, Andreas A1 - Grigoleit, Götz Ulrich A1 - Klinker, Erdwine A1 - Böck, Markus A1 - Samnick, Samuel A1 - Pelzer, Theo A1 - Buck, Andreas K T1 - Peptide receptor radionuclide therapy as a new tool in treatment-refractory sarcoidosis - initial experience in two patients JF - Theranostics N2 - Sarcoidosis is a multisystem granulomatous disorder of unknown etiology that can involve virtually all organ systems. Whereas most patients present without symptoms, progressive and disabling organ failure can occur in up to 10% of subjects. Somatostatin receptor (SSTR)-directed peptide receptor radionuclide therapy (PRRT) has recently received market authorization for treatment of SSTR-positive neuroendocrine tumors. Methods: We describe the first case series comprising two patients with refractory multi-organ involvement of sarcoidosis who received 4 cycles of PRRT. Results: PRRT was well-tolerated without any acute adverse effects. No relevant toxicities could be recorded during follow-up. Therapy resulted in partial response accompanied by a pronounced reduction in pain (patient #1) and stable disease regarding morphology as well as disease activity (patient #2), respectively. Conclusion: Peptide receptor radionuclide therapy in sarcoidosis is feasible and might be a new valuable tool in patients with otherwise treatment-refractory disease. Given the long experience with and good tolerability of PRRT, further evaluation of this new treatment option for otherwise treatment-refractory sarcoidosis in larger patient cohorts is warranted. KW - peptide receptor KW - PRRT KW - sarcoidosis KW - somatostatin receptors KW - radionuclide therapy Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-158983 VL - 8 IS - 3 ER - TY - JOUR A1 - Lapa, Constantin A1 - Kircher, Stefan A1 - Schirbel, Andreas A1 - Rosenwald, Andreas A1 - Kropf, Saskia A1 - Pelzer, Theo A1 - Walles, Thorsten A1 - Buck, Andreas K. A1 - Weber, Wolfgang A. A1 - Wester, Hans-Juergen A1 - Herrmann, Ken A1 - Lückerath, Katharina T1 - Targeting CXCR4 with [\(^{68}\)Ga]Pentixafor: a suitable theranostic approach in pleural mesothelioma? JF - Oncotarget N2 - 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. KW - PET KW - CXCR4 KW - [\(^{68}\)Ga] pentixafor KW - pleural mesothelioma KW - theranostics Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-169989 VL - 8 IS - 57 ER - TY - JOUR A1 - Lapa, Constantin A1 - Linsenmann, Thomas A1 - Lückerath, Katharina A1 - Samnick, Samuel A1 - Herrmann, Ken A1 - Stoffer, Carolin A1 - Ernestus, Ralf-Ingo A1 - Buck, Andreas K. A1 - Löhr, Mario A1 - Monoranu, Camelia-Maria T1 - Tumor-Associated Macrophages in Glioblastoma Multiforme—A Suitable Target for Somatostatin Receptor-Based Imaging and Therapy? JF - PLoS One N2 - Background Glioblastoma multiforme (GBM) is the most common primary brain tumor in adults. Tumor-associated macrophages (TAM) have been shown to promote malignant growth and to correlate with poor prognosis. [1,4,7,10-tetraazacyclododecane-NN′,N″,N′″-tetraacetic acid]-d-Phe1,Tyr3-octreotate (DOTATATE) labeled with Gallium-68 selectively binds to somatostatin receptor 2A (SSTR2A) which is specifically expressed and up-regulated in activated macrophages. On the other hand, the role of SSTR2A expression on the cell surface of glioma cells has not been fully elucidated yet. The aim of this study was to non-invasively assess SSTR2A expression of both glioma cells as well as macrophages in GBM. Methods 15 samples of patient-derived GBM were stained immunohistochemically for macrophage infiltration (CD68), proliferative activity (Ki67) as well as expression of SSTR2A. Anti-CD45 staining was performed to distinguish between resident microglia and tumor-infiltrating macrophages. In a subcohort, positron emission tomography (PET) imaging using \(^{68}Ga-DOTATATE\) was performed and the semiquantitatively evaluated tracer uptake was compared to the results of immunohistochemistry. Results The amount of microglia/macrophages ranged from <10% to >50% in the tumor samples with the vast majority being resident microglial cells. A strong SSTR2A immunostaining was observed in endothelial cells of proliferating vessels, in neurons and neuropile. Only faint immunostaining was identified on isolated microglial and tumor cells. Somatostatin receptor imaging revealed areas of increased tracer accumulation in every patient. However, retention of the tracer did not correlate with immunohistochemical staining patterns. Conclusion SSTR2A seems not to be overexpressed in GBM samples tested, neither on the cell surface of resident microglia or infiltrating macrophages, nor on the surface of tumor cells. These data suggest that somatostatin receptor directed imaging and treatment strategies are less promising in GBM. KW - glioma KW - positron emission tomography KW - glioblastoma multiforme KW - macrophages KW - somatostatin KW - microglial cells KW - immunostaining KW - magnetic resonance imaging Y1 - 2015 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-125498 VL - 10 IS - 3 ER - TY - JOUR A1 - Lapa, Constantin A1 - Lückerath, Katharina A1 - Kleinlein, Irene A1 - Monoranu, Camelia Maria A1 - Linsenmann, Thomas A1 - Kessler, Almuth F. A1 - Rudelius, Martina A1 - Kropf, Saskia A1 - Buck, Andreas K. A1 - Ernestus, Ralf-Ingo A1 - Wester, Hans-Jürgen A1 - Löhr, Mario A1 - Herrmann, Ken T1 - \(^{68}\)Ga-Pentixafor-PET/CT for Imaging of Chemokine Receptor 4 Expression in Glioblastoma JF - Theranostics N2 - Chemokine receptor-4 (CXCR4) has been reported to be overexpressed in glioblastoma (GBM) and to be associated with poor survival. This study investigated the feasibility of non-invasive CXCR4-directed imaging with positron emission tomography/computed tomography (PET/CT) using the radiolabelled chemokine receptor ligand \(^{68}\)Ga-Pentixafor. 15 patients with clinical suspicion on primary or recurrent glioblastoma (13 primary, 2 recurrent tumors) underwent \(^{68}\)Ga-Pentixafor-PET/CT for assessment of CXCR4 expression prior to surgery. O-(2-\(^{18}\)F-fluoroethyl)-L-tyrosine (\(^{18}\)F-FET) PET/CT images were available in 11/15 cases and were compared visually and semi-quantitatively (SUV\(_{max}\), SUV\(_{mean}\)). Tumor-to-background ratios (TBR) were calculated for both PET probes. \(^{68}\)Ga-Pentixafor-PET/CT results were also compared to histological CXCR4 expression on neuronavigated surgical samples. \(^{68}\)Ga-Pentixafor-PET/CT was visually positive in 13/15 cases with SUV\(_{mean}\) and SUV\(_{max}\) of 3.0±1.5 and 3.9±2.0 respectively. Respective values for \(^{18}\)F-FET were 4.4±2.0 (SUV\(_{mean}\)) and 5.3±2.3 (SUV\(_{max}\)). TBR for SUV\(_{mean}\) and SUV\(_{max}\) were higher for \(^{68}\)Ga-Pentixafor than for \(^{18}\)F-FET (SUV\(_{mean}\) 154.0±90.7 vs. 4.1±1.3; SUV\(_{max}\) 70.3±44.0 and 3.8±1.2, p<0.01), respectively. Histological analysis confirmed CXCR4 expression in tumor areas with high \(^{68}\)Ga-Pentixafor uptake; regions of the same tumor without apparent \(^{68}\)Ga-Pentixafor uptake showed no or low receptor expression. In this pilot study, \(^{68}\)Ga-Pentixafor retention has been observed in the vast majority of glioblastoma lesions and served as readout for non-invasive determination of CXCR4 expression. Given the paramount importance of the CXCR4/SDF-1 axis in tumor biology, \(^{68}\)Ga-Pentixafor-PET/CT might prove a useful tool for sensitive, non-invasive in-vivo quantification of CXCR4 as well as selection of patients who might benefit from CXCR4-directed therapy. KW - imaging KW - chemokine receptor-4 KW - glioblastoma KW - positron emission tomography/computed tomography KW - \(^{68}\)Ga-Pentixafor Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-168174 VL - 6 IS - 3 ER - TY - JOUR A1 - Lapa, Constantin A1 - Reiter, Theresa A1 - Kircher, Malte A1 - Schirbel, Andreas A1 - Werner, Rudolf A. A1 - Pelzer, Theo A1 - Pizarro, Carmen A1 - Skowasch, Dirk A1 - Thomas, Lena A1 - Schlesinger-Irsch, Ulrike A1 - Thomas, Daniel A1 - Bundschuh, Ralph A. A1 - Bauer, Wolfgang R. A1 - Gartner, Florian C. T1 - Somatostatin receptor based PET/CT in patients with the suspicion of cardiac sarcoidosis: an initial comparison to cardiac MRI JF - Oncotarget N2 - Diagnosis of cardiac sarcoidosis is often challenging. Whereas cardiac magnetic resonance imaging (CMR) and positron emission tomography/computed tomography (PET/CT) with \(^{18}\)F-fluorodeoxyglucose (FDG) are most commonly used to evaluate patients, PET/CT using radiolabeled somatostatin receptor (SSTR) ligands for visualization of inflammation might represent a more specific alternative. This study aimed to investigate the feasibility of SSTR–PET/CT for detecting cardiac sarcoidosis in comparison to CMR. 15 patients (6 males, 9 females) with sarcoidosis and suspicion on cardiac involvement underwent SSTR-PET/CT imaging and CMR. Images were visually scored. The AHA 17-segment model of the left myocardium was used for localization and comparison of inflamed myocardium for both imaging modalities. In semi-quantitative analysis, mean (SUV\(_{mean}\)) and maximum standardized uptake values (SUV\(_{max}\)) of affected myocardium were calculated and compared with both remote myocardium and left ventricular (LV) cavity. SSTR-PET was positive in 7/15, CMR in 10/15 patients. Of the 3 CMR+/PET- subjects, one patient with minor involvement (<25% of wall thickness in CMR) was missed by PET. The remaining two CMR+/PET- patients displayed no adverse cardiac events during follow-up. In the 17-segment model, PET/CT yielded 27 and CMR 29 positive segments. Overall concordance of the 2 modalities was 96.1% (245/255 segments analyzed). SUV\(_{mean}\) and SUV\(_{max}\) in inflamed areas were 2.0±1.2 and 2.6±1.2, respectively. The lesion-to-remote myocardium and lesion-to-LV cavity ratios were 1.8±0.2 and 1.9±0.2 for SUV\(_{mean}\) and 2.0±0.3 and 1.7±0.3 for SUV\(_{max}\), respectively. Detection of cardiac sarcoidosis by SSTR-PET/CT is feasible. Our data warrant further analysis in larger prospective series. KW - sarcoidosis KW - PET KW - SSTR KW - somatostatin receptor KW - DOTATOC Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-175423 VL - 7 IS - 47 ER - TY - JOUR A1 - Lapa, Constantin A1 - Schreder, Martin A1 - Schirbel, Andreas A1 - Samnick, Samuel A1 - Kortüm, Klaus Martin A1 - Herrmann, Ken A1 - Kropf, Saskia A1 - Einsele, Herrmann A1 - Buck, Andreas K. A1 - Wester, Hans-Jürgen A1 - Knop, Stefan A1 - Lückerath, Katharina T1 - [\(^{68}\)Ga]Pentixafor-PET/CT for imaging of chemokine receptor CXCR4 expression in multiple myeloma - comparison to [\(^{18}\)F]FDG and laboratory values JF - Theranostics N2 - Chemokine (C-X-C motif) receptor 4 (CXCR4) is a key factor for tumor growth and metastasis in several types of human cancer including multiple myeloma (MM). Proof-of-concept of CXCR4-directed radionuclide therapy in MM has recently been reported. This study assessed the diagnostic performance of the CXCR4-directed radiotracer [\(^{68}\)Ga]Pentixafor in MM and a potential role for stratifying patients to CXCR4-directed therapies. Thirty-five patients with MM underwent [\(^{68}\)Ga]Pentixafor-PET/CT for evaluation of eligibility for endoradiotherapy. In 19/35 cases, [\(^{18}\)F]FDG-PET/CT for correlation was available. Scans were compared on a patient and on a lesion basis. Tracer uptake was correlated with standard clinical parameters of disease activity. [\(^{68}\)Ga]Pentixafor-PET detected CXCR4-positive disease in 23/35 subjects (66%). CXCR4-positivity at PET was independent from myeloma subtypes, cytogenetics or any serological parameters and turned out as a negative prognostic factor. In the 19 patients in whom a comparison to [\(^{18}\)F]FDG was available, [\(^{68}\)Ga]Pentixafor-PET detected more lesions in 4/19 (21%) subjects, [\(^{18}\)F]FDG proved superior in 7/19 (37%). In the remaining 8/19 (42%) patients, both tracers detected an equal number of lesions. [\(^{18}\)F]FDG-PET positivity correlated with [\(^{68}\)Ga]Pentixafor-PET positivity (p=0.018). [\(^{68}\)Ga]Pentixafor-PET provides further evidence that CXCR4 expression frequently occurs in advanced multiple myeloma, representing a negative prognostic factor and a potential target for myeloma specific treatment. However, selecting patients for CXCR4 directed therapies and prognostic stratification seem to be more relevant clinical applications for this novel imaging modality, rather than diagnostic imaging of myeloma. KW - medicine KW - multiple myeloma KW - FDG KW - molecular imaging KW - CXCR4 KW - PET KW - radionuclide therapy KW - theranostics Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-172106 VL - 7 IS - 1 ER - TY - JOUR A1 - Lapa, Constantin A1 - Werner, Rudolf A. A1 - Bluemel, Christina A1 - Lueckerath, Katharina A1 - Muegge, Dirk O. A1 - Strate, Alexander A1 - Haenscheid, Heribert A1 - Schirbel, Andreas A1 - Allen-Auerbach, Martin S. A1 - Bundschuh, Ralph A. A1 - Buck, Andreas K. A1 - Herrmann, Ken T1 - Prediction of clinically relevant hyperkalemia in patients treated with peptide receptor radionuclide therapy JF - EJNMMI Research N2 - Background Peptide receptor radionuclide therapy (PRRT) is applied in patients with advanced neuroendocrine tumors. Co-infused amino acids (AA) should prevent nephrotoxicity. The aims of this study were to correlate the incidence of AA-induced hyperkalemia (HK) (≥5.0 mmol/l) and to identify predictors of AA-induced severe HK (>6.0). Methods In 38 patients, standard activity of \(^{177}Lu\)-labelled somatostatin analogs was administered. Pre-therapeutic kidney function was assessed by renal scintigraphy and laboratory tests. For kidney protection, AA was co-infused. Biochemical parameters (potassium, glomerular filtration rate, creatinine, blood urea nitrogen (BUN), sodium, phosphate, chloride, and lactate dehydrogenase (LDH)) were obtained prior to 4 and 24 h after the AA infusion. Incidence of HK (≥5.0) was correlated with pre-therapeutic kidney function and serum parameters. Formulas for the prediction of severe hyperkalemia (>6.0) were computed and prospectively validated. Results At 4 h, HK (≥5.0) was present in 94.7% with severe HK (>6.0) in 36.1%. Values normalized after 24 h in 84.2%. Pre-therapeutic kidney function did not correlate with the incidence of severe HK. Increases in K+ were significantly correlated with decreases in phosphate (r = −0.444, p < 0.005) and increases in BUN (r = 0.313, p = 0.056). A baseline BUN of >28 mg/dl had a sensitivity of 84.6% and a specificity of 60.0% (AUC = 0.75) in predicting severe HK of >6.0 (phosphate, AUC = 0.37). Computing of five standard serum parameters (potassium, BUN, sodium, phosphate, LDH) resulted in a sensitivity of 88.9% and a specificity of 79.3% for the prediction of severe HK >6.0 (accuracy = 81.6%). Conclusions A combination of serum parameters predicted prospectively the occurrence of relevant HK with an accuracy of 81.6% underlining its potential utility for identifying ‘high-risk’ patients prone to PRRT. KW - amino acids KW - kidney function KW - hyperkalemia KW - PRRT KW - NET KW - MAG3 Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-124963 VL - 4 IS - 74 ER -