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 - 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 - 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 -