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 - 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 - 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 - 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 - 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 - 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 - 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 - 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 - 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 - 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 -