TY - JOUR A1 - Bluemel, Christina A1 - Linke, Fraenze A1 - Herrmann, Ken A1 - Simunovic, Iva A1 - Eiber, Matthias A1 - Kestler, Christian A1 - Buck, Andreas K. A1 - Schirbel, Andreas A1 - Bley, Thorsten A. A1 - Wester, Hans-Juergen A1 - Vergho, Daniel A1 - Becker, Axel T1 - Impact of \(^{68}\)Ga-PSMA PET/CT on salvage radiotherapy planning in patients with prostate cancer and persisting PSA values or biochemical relapse after prostatectomy JF - EJNMMI Research N2 - Background Salvage radiotherapy (SRT) is clinically established in prostate cancer (PC) patients with PSA persistence or biochemical relapse (BCR) after prior radical surgery. PET/CT imaging prior to SRT may be performed to localize disease recurrence. The recently introduced \(^{68}\)Ga-PSMA outperforms other PET tracers for detection of recurrence and is therefore expected also to impact radiation planning. Forty-five patients with PSA persistence (16 pts) or BCR (29 pts) after prior prostatectomy, scheduled to undergo SRT of the prostate bed, underwent \(^{68}\)Ga-PSMA PET/CT. The median PSA level was 0.67 ng/ml. The impact of \(^{68}\)Ga-PSMA PET/CT on the treatment decision was assessed. Patients with oligometastatic (≤5 lesions) PC underwent radiotherapy (RT), with the extent of the RT area and dose escalation being based on PET positivity. Results Suspicious lesions were detected in 24/45 (53.3 %) patients. In 62.5 % of patients, lesions were only detected by 68Ga-PSMA PET. Treatment was changed in 19/45 (42.2 %) patients, e.g., extending SRT to metastases (9/19), administering dose escalation in patients with morphological local recurrence (6/19), or replacing SRT by systemic therapy (2/19). 38/45 (84.4 %) followed the treatment recommendation, with data on clinical follow-up being available in 21 patients treated with SRT. All but one showed biochemical response (mean PSA decline 78 ± 19 %) within a mean follow-up of 8.12 ± 5.23 months. Conclusions \(^{68}\)Ga-PSMA PET/CT impacts treatment planning in more than 40 % of patients scheduled to undergo SRT. Future prospective studies are needed to confirm this significant therapeutic impact on patients prior to SRT. KW - prostate cancer KW - salvage radiotherapy KW - PSMA KW - PET/CT KW - recurrence Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-147798 VL - 6 IS - 78 ER - TY - JOUR A1 - Brumberg, Joachim A1 - Küsters, Sebastian A1 - Al-Momani, Ehab A1 - Marotta, Giorgio A1 - Cosgrove, Kelly P. A1 - van Dyck, Christopher H. A1 - Herrmann, Ken A1 - Homola, György A. A1 - Pezzoli, Gianni A1 - Buck, Andreas K. A1 - Volkmann, Jens A1 - Samnick, Samuel A1 - Isaias, Ioannis U. T1 - Cholinergic activity and levodopa-induced dyskinesia: a multitracer molecular imaging study JF - Annals of Clinical and Translational Neurology N2 - Objective: To investigate the association between levodopa‐induced dyskinesias and striatal cholinergic activity in patients with Parkinson's disease. Methods: This study included 13 Parkinson's disease patients with peak‐of‐dose levodopa‐induced dyskinesias, 12 nondyskinetic patients, and 12 healthy controls. Participants underwent 5‐[\(^{123}\)I]iodo‐3‐[2(S)‐2‐azetidinylmethoxy]pyridine single‐photon emission computed tomography, a marker of nicotinic acetylcholine receptors, [\(^{123}\)I]N‐ω‐fluoropropyl‐2β‐carbomethoxy‐3β‐(4‐iodophenyl)nortropane single‐photon emission computed tomography, to measure dopamine reuptake transporter density and 2‐[\(^{18}\)F]fluoro‐2‐deoxyglucose positron emission tomography to assess regional cerebral metabolic activity. Striatal binding potentials, uptake values at basal ganglia structures, and correlations with clinical variables were analyzed. Results: Density of nicotinic acetylcholine receptors in the caudate nucleus of dyskinetic subjects was similar to that of healthy controls and significantly higher to that of nondyskinetic patients, in particular, contralaterally to the clinically most affected side. Interpretation: Our findings support the hypothesis that the expression of dyskinesia may be related to cholinergic neuronal excitability in a dopaminergic‐depleted striatum. Cholinergic signaling would play a role in maintaining striatal dopaminergic responsiveness, possibly defining disease phenotype and progression. KW - levodopa-induced dyskinesia KW - cholinergic activity KW - Parkinson’s disease Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-170406 VL - 4 IS - 9 ER - TY - JOUR A1 - Buder, Kristina A1 - Lapa, Constantin A1 - Kreissl, Michael C. A1 - Schirbel, Andreas A1 - Herrmann, Ken A1 - Schnack, Alexander A1 - Bröcker, Eva-Bettina A1 - Goebeler, Matthias A1 - Buck, Andreas K. A1 - Becker, Jürgen C. T1 - "Somatostatin receptor expression in Merkel cell carcinoma as target for molecular imaging" N2 - Background Merkel cell carcinoma (MCC) is a rare cutaneous neoplasm with increasing incidence, aggressive behavior and poor prognosis. Somatostatin receptors (SSTR) are expressed in MCC and represent a potential target for both imaging and treatment. Methods To non-invasively assess SSTR expression in MCC using PET and the radiotracers [68Ga]DOTA-D-Phe1-Tyr3-octreotide (DOTATOC) or -octreotate (DOTATATE) as surrogate for tumor burden. In 24 patients with histologically proven MCC SSTR-PET was performed and compared to results of computed tomography (CT). Results SSTR-PET detected primary and metastatic MCC lesions. On a patient-based analysis, sensitivity of SSTR-PET was 73% for nodal metastases, 100% for bone, and 67% for soft-tissue metastases, respectively. Notably, brain metastases were initially detected by SSTR-PET in 2 patients, whereas liver and lung metastases were diagnosed exclusively by CT. SSTR-PET showed concordance to CT results in 20 out of 24 patients. Four patients (17%) were up-staged due to SSTR-PET and patient management was changed in 3 patients (13%). Conclusion SSTR-PET showed high sensitivity for imaging bone, soft tissue and brain metastases, and particularly in combination with CT had a significant impact on clinical stage and patient management. KW - Merkel cell carcinoma KW - Molecular imaging KW - Somatostatin receptor expression KW - Positron emission tomography Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-110326 ER - TY - JOUR A1 - Graf, Nicolas A1 - Li, Zhoulei A1 - Herrmann, Ken A1 - Weh, Daniel A1 - Aichler, Michaela A1 - Slawska, Jolanta A1 - Walch, Axel A1 - Peschel, Christian A1 - Schwaiger, Markus A1 - Buck, Andreas K. A1 - Dechow, Tobias A1 - Keller, Ulrich T1 - Positron emission tomographic monitoring of dual phosphatidylinositol-3-kinase and mTOR inhibition in anaplastic large cell lymphoma JF - Oncotargets and Therapy N2 - Background: Dual phosphatidylinositol-3-kinase (PI3K)/mammalian target of rapamycin (mTOR) inhibition offers an attractive therapeutic strategy in anaplastic large cell lymphoma depending on oncogenic nucleophosmin-anaplastic lymphoma kinase (NPM-ALK) signaling. We tested the efficacy of a novel dual PI3K/mTOR inhibitor, NVP-BGT226 (BGT226), in two anaplastic large cell lymphoma cell lines in vitro and in vivo and performed an early response evaluation with positron emission tomography (PET) imaging using the standard tracer, 2-deoxy-2-[F-18] fluoro-D-glucose (FDG) and the thymidine analog, 3'-deoxy-3'-[F-18] fluorothymidine (FLT). Methods: The biological effects of BGT226 were determined in vitro in the NPM-ALK positive cell lines SU-DHL-1 and Karpas299 by 3-[4,5-Dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide assay, propidium iodide staining, and biochemical analysis of PI3K and mTOR downstream signaling. FDG-PET and FLT-PET were performed in immunodeficient mice bearing either SU-DHL-1 or Karpas299 xenografts at baseline and 7 days after initiation of treatment with BGT226. Lymphomas were removed for immunohistochemical analysis of proliferation and apoptosis to correlate PET findings with in vivo treatment effects. Results: SU-DHL-1 cells showed sensitivity to BGT226 in vitro, with cell cycle arrest in G0/G1 phase and an IC50 in the low nanomolar range, in contrast with Karpas299 cells, which were mainly resistant to BGT226. In vivo, both FDG-PET and FLT-PET discriminated sensitive from resistant lymphoma, as indicated by a significant reduction of tumor-to-background ratios on day 7 in treated SU-DHL-1 lymphoma-bearing animals compared with the control group, but not in animals with Karpas299 xenografts. Imaging results correlated with a marked decrease in the proliferation marker Ki67, and a slight increase in the apoptotic marker, cleaved caspase 3, as revealed by immunostaining of explanted lymphoma tissue. Conclusion: Dual PI3K/mTOR inhibition using BGT226 is effective in ALK-positive anaplastic large cell lymphoma and can be monitored with both FDG-PET and FLT-PET early on in the course of therapy. KW - mammalian target of rapamycin KW - phosphatidylinositol-3-kinase KW - lymphoma KW - early response KW - NVP-BGT226 KW - non-hodgkins-lymphoma KW - signaling pathway KW - FDG-PET KW - in-vivo KW - target KW - tumor KW - imaging proliferation KW - inhibition KW - positron emission tomography Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-117915 VL - 7 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 - 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 - 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, 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 -