Frederik A Verburg

University Hospital RWTH Aachen, Aachen, North Rhine-Westphalia, Germany

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Publications (135)481.19 Total impact

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    ABSTRACT: Purpose: To compare mutation analysis of cytology specimens and (99m)Tc-MIBI thyroid scintigraphy for differentiating benign from malignant thyroid nodules in patients with a cytological reading of follicular neoplasm. Methods: Patients ≥18 years of age with a solitary hypofunctioning thyroid nodule (≥10 mm), normal thyrotropin and calcitonin levels, and a cytological diagnosis of follicular neoplasm were prospectively enrolled. Mutation analysis and (99m)Tc-MIBI scintigraphy were performed and patients were subsequently operated on to confirm or exclude a malignant lesion. Mutations for KRAS, HRAS and NRAS and for BRAF and translocations of PAX8/PPARγ, RET/PTC1 and RET/PTC3 were investigated. Static thyroid scintigraphic images were acquired 10 and 60 min after intravenous injection of 200 MBq of (99m)Tc-MIBI and visually assessed. Additionally, the MIBI washout index was calculated using a semiquantitative method. Results: In our series, 26 % of nodules with a follicular pattern on cytology were malignant with a prevalence of follicular carcinomas. (99m)Tc-MIBI scintigraphy was found to be significantly more accurate (positive likelihood ratio 4.56 for visual assessment and 12.35 for semiquantitative assessment) than mutation analysis (positive likelihood ratio 1.74). A negative (99m)Tc-MIBI scan reliably excluded malignancy. Conclusion: In patients with a thyroid nodule cytologically diagnosed as a follicular proliferation, semiquantitative analysis of (99m)Tc-MIBI scintigraphy should be the preferred method for differentiating benign from malignant nodules. It is superior to molecular testing for the presence of differentiated thyroid cancer-associated mutations in fine-needle aspiration cytology sample material.
    Full-text · Article · Dec 2015 · European journal of nuclear medicine and molecular imaging
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    ABSTRACT: Purpose: To examine the relationship between the extent of disease determined by [(68)Ga]PSMA-HBED-CC-PET/CT and the important clinical measures prostate-specific antigen (PSA), PSA doubling time (PSAdt) and Gleason score. Methods: We retrospectively studied the first 155 patients with recurrent prostate cancer (PCA) referred to our university hospital for [(68)Ga]PSMA-HBED-CC PET/CT. Results: PET/CT was positive in 44 %, 79 % and 89 % of patients with PSA levels of ≤1, 1 - 2 and ≥2 ng/ml, respectively. Patients with high PSA levels showed higher rates of local prostate tumours (p < 0.001), and extrapelvic lymph node (p = 0.037) and bone metastases (p = 0.013). A shorter PSAdt was significantly associated with pelvic lymph node (p = 0.026), extrapelvic lymph node (p = 0.001), bone (p < 0.001) and visceral (p = 0.041) metastases. A high Gleason score was associated with more frequent pelvic lymph node metastases (p = 0.039). In multivariate analysis, both PSA and PSAdt were independent determinants of scan positivity and of extrapelvic lymph node metastases. PSAdt was the only independent marker of bone metastases (p = 0.001). Of 20 patients with a PSAdt <6 months and a PSA ≥2 ng/ml, 19 (95 %) had a positive scan and 12 (60 %) had M1a disease. Of 14 patients with PSA <1 ng/ml and PSAdt >6 months, only 5 (36 %) had a positive scan and 1 (7 %) had M1a disease. Conclusion: [(68)Ga]PSMA-HBED-CC PET/CT will identify PCA lesions even in patients with very low PSA levels. Higher PSA levels and shorter PSAdt are independently associated with scan positivity and extrapelvic metastases, and can be used for patient selection for [(68)Ga]PSMA-HBED-CC PET/CT.
    No preview · Article · Nov 2015 · European Journal of Nuclear Medicine
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    ABSTRACT: Purpose: Based on a single older study it is established dogma that TSH levels should be ≥30 mU/l at the time of postoperative (131)I ablation in differentiated thyroid cancer (DTC) patients. We sought to determine whether endogenous TSH levels, i.e. after levothyroxine withdrawal, at the time of ablation influence ablation success rates, recurrence-free survival and DTC-related mortality. Methods: A total of 1,873 patients without distant metastases referred for postoperative adjuvant (131)I therapy were retrospectively included from 1991 onwards. Successful ablation was defined as stimulated Tg <1 μg/l. Results: Age, gender and the presence of lymph node metastases were independent determinants of TSH levels at the time of ablation. TSH levels were not significantly related to ablation success rates (p = 0.34), recurrence-free survival (p = 0.29) or DTC -elated mortality (p = 0.82), but established risk factors such as T-stage, lymph node metastases and age were. Ablation was successful in 230 of 275 patients (83.6 %) with TSH <30 mU/l and in 1,359 of 1,598 patients (85.0 %) with TSH ≥30 mU/l. The difference was not significant (p = 0.55). Of the whole group of 1,873 patients, 21 had recurrent disease. There were no significant differences in recurrence rates between patients with TSH <30 mU/l and TSH ≥30 mU/l (p = 0.16). Ten of the 1,873 patients died of DTC. There were no significant differences in DTC-specific survival between patients with TSH <30 mU/l and TSH ≥30 mU/l (p = 0.53). Conclusion: The precise endogenous TSH levels at the time of (131)I ablation are not related to the ablation success rates, recurrence free survival and DTC related mortality. The established dogma that TSH levels need to be ≥30 mU/l at the time of (131)I ablation can be discarded.
    Full-text · Article · Oct 2015 · European Journal of Nuclear Medicine
  • H. Hänscheid · M. Lassmann · F. A. Verburg
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    ABSTRACT: The iodine isotope I-131 has been used in nuclear medicine for several decades to treat both benign and malignant thyroid diseases. The therapy is effective and safe and insensitive to variations in the activity dosage of I-131. Individualization of therapy in order to limit the administered activity to the lowest amount necessary to successfully treat diseased thyrocytes while minimizing exposure to healthy organs requires performing dosimetry through measurement of the individual iodine kinetics. This review discusses the concepts of dosimetry used for patients with thyroid disorders and compiles information on the present evidence for superiority of individualization of therapy by dosimetric assessments. Two main concepts of individualized treatment are used for patients with differentiated thyroid carcinoma: (a) the assessment of the specific absorbed dose to the blood as a substitute for the red marrow dose in order to target at a specific blood dose from therapy and (b) the administration of the I-131 activity determined by lesion dosimetry to be necessary to achieve a fixed absorbed dose to the tumour which is known to be effective in most of the cases. The first concept is mainly used to safely administer the highest tolerable activity, thus enhancing the absorbed dose to the tumour. Increasing evidence exists that patients with advanced disease benefit from this dose optimization. The second concept becomes increasingly feasible with the improvements in dosimetry introduced by advanced imaging techniques like I-124 PET/CT, but bears the inherent risk of under-dosing the patient. Studies reporting response in tumours are not consistent regarding the absorbed dose necessary to certainly eliminate the lesion. In the treatment of benign thyroid diseases, most studies comparing regimes with calculated and estimated activity dosage did not find improved rates of cure and side effects in patients with measured kinetics. A few studies with advanced dosimetric concepts found good dose–response relations. Individualization of radioiodine therapy in the treatment of thyroid disorders still is not used to its full potential. Recently developed imaging techniques like SPECT/CT and PET/CT, enabling 3-dimensional measurement of dose distributions, allow considerable improvements in dosimetry. Prospective randomized trials with appropriate and controlled dosimetry are necessary to provide conclusive information on the value of individualized treatment planning and to identify the major confounding variables responsible for treatment failure.
    No preview · Article · Oct 2015
  • Felix M Mottaghy · Florian F Behrendt · Frederik A Verburg

    No preview · Article · Oct 2015 · European Journal of Nuclear Medicine
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    ABSTRACT: I-123-IBZM-SPECT is often used to differentiate between idiopathic Parkinson's syndrome and atypical parkinsonian syndromes. The aim of this study was to compare three different procedures to quantify the receptor availability of striatal dopamine D2 receptors. (a) Manual quantification performed using individually adjusted volume of interests sets (mVoi). (b) Automatic quantification applying the commercially available Hermes BRASS software (BRASS). (c) Automatic quantification applying the open-source software IBZM Toolbox (TBX). Using the three methods, we analyzed 100 scans. For the mVOI methods, three different investigators (two experienced, one inexperienced) carried out the analysis. We compared the different methods with each other and with the reference standard established by clinical follow-up. The diagnostic performance was assessed by calculating receiver-operating characteristic (ROC) curves. Correlation analyses resulted in the following: mVOI versus BRASS (r=0.694) (P<0.005), mVOI versus TBX (r=0.557) (P<0.005); BRASS versus TBX (r=0.466) (P<0.005). We found a fair agreement for mVOI versus BRASS; slight agreement for mVOI versus TBX; and fair agreement for BRASS versus TBX. Moreover, we found a substantial agreement between the experienced investigators, but not with the inexperienced investigator in the case of mVOI. The ROC analysis shows the largest area under the ROC curve (Az=0.7295) for mVOI, followed by BRASS (Az=0.709) and TBX (Az=0.627). In direct comparison, the manual quantification used by experienced observers shows the best results, although it does not differ significantly from the commercial Hermes BRASS software. Both are superior to TBX.
    No preview · Article · Jul 2015 · Nuclear Medicine Communications
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    ABSTRACT: To compare and outline the beneficial skills of combined (68)Ga-DOTATATE positron emission tomography (PET) with concurrent contrast enhanced X-ray computed tomography (ceCT) against stand-alone ceCT in 54 patients with neuroendocrine tumours (NET). Patients with histologically confirmed NET and available follow-up of at least 6 months (median 12.6 months; range 6.1-23.2) were included. PET/CT and ceCT images were initially analyzed separately by two blinded nuclear medicine physicians and two radiologists, respectively. In a second step all four physicians reviewed all detected lesions together reaching a consensus-grading for PET/ceCT. The results were then compared to the reference standard consisting of clinical follow-up data. With regard to true positive lesions, PET/ceCT vs. stand alone ceCT detected 139 vs. 48 bone-lesions, 106 vs. 71 lymph node metastases and 26 vs. 26 pulmonary lesions. On a per-patient basis, PET/ceCT achieved a higher sensitivity (100% vs. 47%) and specificity (89% vs. 49%) for bone lesions than ceCT. For lymph nodes the effect was similar (sensitivity 92% vs. 64% and specificity 83% vs. 59%). For the detection of pulmonary lesions the sensitivity was identical (100%) while specificity of PET/ceCT was superior to ceCT-alone (95% vs. 82%). In summary, the use of (68)Ga-DOTATATE PET/ceCT leads to an increase in sensitivity and specificity in the detection of extra-hepatic NET metastases compared to stand-alone ceCT. Therefore, (68)Ga-DOTATATE PET/ceCT should be the imaging modality of choice in patients with NET. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
    No preview · Article · Jun 2015 · European journal of radiology
  • Frederik A Verburg
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    ABSTRACT: Thyroid surgery is one of the more common surgical procedures in Germany. This is in contrast with the situation in some other countries, where this procedure is performed comparatively rarely. In this paper the number of thyroid surgeries in Germany is compared with other western countries (Netherlands, USA, England). In contrast to e. g. the USA and England the number of thyroid surgeries in Germany is declining, however with approximately 109/100 000/year in 2012 is still elevated (Netherlands: 16/100 000/year, USA: at least 42/100 000/year, England: at least 27/100 000/year). Possible contributing factors to this higher number of thyroid surgeries in Germany are explored. These factors include iodine deficiency, the frequent use of advanced diagnostics such as ultrasound, insufficient use of preoperative diagnostic measures such as fine needle biopsy and the practice of "defensive medicine". How much each of these factors contributes is however unclear.
    No preview · Article · Jun 2015 · Nuklearmedizin
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    ABSTRACT: In adult differentiated thyroid cancer (DTC) patients, successful ablation and the number of (131)I therapies needed carry a prognostic significance. The goal was to assess the prognosis of DTC in children and adolescents treated in our centre in relation to the number of treatments needed and to establish the determinants of both complete remission (CR) and successful ablation. Seventy-six DTC patients <21 years of age at diagnosis were included. Recurrence and death rates, rates of CR (=negative stimulated thyroglobulin, negative neck ultrasound and negative (131)I whole-body scintigraphy) and successful ablation (=CR after initial (131)I therapy) were studied. No patients died of DTC. Seven patients were treated by surgery alone and did not show signs of recurrence during follow-up. Of the 69 patients also treated with (131)I therapy, 47 patients achieved CR, 25 of whom had successful ablation. In multivariate analysis, female gender and the absence of distant metastases were independent determinants of a higher CR rate. Female gender, lower T stage and higher (131)I activity (successful ablation, median activity 3.1 GBq, unsuccessful ablation 2.6 GBq) were determinants of a higher rate of successful ablation. After (131)I therapy no patient showed recurrence after reaching CR or disease progression if CR was not reached. In our paediatric DTC population prognosis is extremely good with no deaths or recurrences occurring regardless of the number of (131)I therapies needed or whether CR was reached. The determinants of CR and successful ablation can be used to optimize the chance of therapy success.
    No preview · Article · Jun 2015 · European Journal of Nuclear Medicine
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    ABSTRACT: to determine whether the first three months after 131I ablation is too early to perform radioiodine diagnostic whole body scintigraphy (dxWBS) in differentiated thyroid carcinoma patients. The files of 462 patients who were treated for DTC in our hospital were reviewed. All patients underwent surgical thyroidectomy. 146 patients had data available on a. a dxWBS which was performed less than four months (max 120 days) after 131I ablation with concurrent stimulated TSH stimulated thyroglobulin (Tg) measurement without further therapeutic measures between ablation and dxWBS and b. a second dxWBS or 131I therapy (rxWBS) within 1.5 years after ablation. A discordance between the initial and follow-up scan was found in 25/129 (19%) patients: of 54 patients with a positive initial dxWBS, scan results of a second dxWBS or rxWBS obtained with a suitable distance to the initial scan contradicted the initial one in 15 patients (27%). New lesions were discovered in 10/74 negative first dxWBS cases (14%). A discordance between the initial and follow-up stimulated Tg was found in 5/129 (4%) patients: 2/90 (2%) of patients with a negative stimulated Tg at initial dxWBS subsequently showed a positive results whereas 3/29 (10%) patients with an initially positive Tg showed a negative Tg level at the second procedure. Less than four months after 131I ablation is too early to perform radioiodine diagnostic whole body scintigraphy with concurrent TSH stimulated Tg measurement. The identification of the right, later, timepoint however requires further research.
    No preview · Article · Jun 2015 · Nuklearmedizin
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    ABSTRACT: BACKGROUND: Fatty acid synthase (FASN) is crucial to de novo long-chain fatty acid synthesis, needed to meet cancer cells' increased demands for membrane, energy, and protein production. METHODS: We investigated FASN overexpression as a therapeutic and chemosensitization target in ovarian cancer tissue, cell lines, and primary cell cultures. FASN expression at mRNA and protein levels was determined by quantitative real-time polymerase chain reaction and immunoblotting and immunohistochemistry, respectively. FASN inhibition's impact on cell viability, apoptosis, and fatty acid metabolism was assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium-bromide assay, cell death detection enzyme-linked immunosorbent assay, immunoblotting, and 18 F-fluoromethylcholine uptake measurement, respectively. RESULTS: Relative to that in healthy fallopian tube tissue, tumor tissues had 1.8-fold average FASN protein overexpression; cell lines and primary cultures had 11-fold-100-fold mRNA and protein overexpression. In most samples, the FASN inhibitor cerulenin markedly decreased FASN expression and cell viability and induced apoptosis. Unlike concomitant administration, sequential cerulenin/cisplatin treatment reduced cisplatin's half maximal inhibitory concentration profoundly (up to 54%) in a cisplatin-resistant cell line, suggesting platinum (re)sensitization. Cisplatin-resistant cells displayed lower 18 F-fluoro-methylcholine uptake than did cisplatin-sensitive cells, suggesting that metabolic imaging might help guide therapy. CONCLUSIONS: FASN inhibition induced apoptosis in chemosensitive and platinum-resistant ovarian cancer cells and may reverse cisplatin resistance.
    No preview · Article · May 2015 · Journal of Translational Medicine
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    ABSTRACT: Fatty acid synthase (FASN) is crucial to de novo long-chain fatty acid synthesis, needed to meet cancer cells' increased demands for membrane, energy, and protein production. We investigated FASN overexpression as a therapeutic and chemosensitization target in ovarian cancer tissue, cell lines, and primary cell cultures. FASN expression at mRNA and protein levels was determined by quantitative real-time polymerase chain reaction and immunoblotting and immunohistochemistry, respectively. FASN inhibition's impact on cell viability, apoptosis, and fatty acid metabolism was assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium-bromide assay, cell death detection enzyme-linked immunosorbent assay, immunoblotting, and (18) F-fluoromethylcholine uptake measurement, respectively. Relative to that in healthy fallopian tube tissue, tumor tissues had 1.8-fold average FASN protein overexpression; cell lines and primary cultures had 11-fold-100-fold mRNA and protein overexpression. In most samples, the FASN inhibitor cerulenin markedly decreased FASN expression and cell viability and induced apoptosis. Unlike concomitant administration, sequential cerulenin/cisplatin treatment reduced cisplatin's half maximal inhibitory concentration profoundly (up to 54%) in a cisplatin-resistant cell line, suggesting platinum (re)sensitization. Cisplatin-resistant cells displayed lower (18) F-fluoro-methylcholine uptake than did cisplatin-sensitive cells, suggesting that metabolic imaging might help guide therapy. FASN inhibition induced apoptosis in chemosensitive and platinum-resistant ovarian cancer cells and may reverse cisplatin resistance.
    Full-text · Article · May 2015 · Journal of Translational Medicine
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    ABSTRACT: AimInternational guidelines significantly diverge on the effectiveness of thyroid scintigraphy (TS) in the initial work-up of thyroid nodules. In particular, the role of TS to detect or exclude the presence of autonomously functioning thyroid nodules (AFTN) in patients with normal serum thyrotropin (TSH) is still a matter to debate. Here we aimed to review the literature on the prevalence of normal TSH value out of patients with AFTN, and meta-analyze data of the retrieved eligible papers.MethodsA comprehensive literature search of studies published from January 2000 to December 2014 on AFTN detected by TS was performed. Records reporting serum TSH values in AFTN were selected. Pooled prevalence of AFTN with normal TSH values was calculated on a per-patient analysis including 95% confidence intervals (95%CI).ResultsEight records including 2761 AFTN were selected for the meta-analysis. Pooled prevalence of AFTN with normal TSH detected by TS was 50% (95%CI: 32-68%). Selection bias in the included studies and heterogeneity among studies were potential limitations of the meta-analysis.Conclusions Present meta-analysis shows that about one in two patients with AFTN demonstrated by TS has a TSH value within normal references. As a consequence, TSH measurement may not be considered as effective as a single tool to detect or exclude AFTN, and TS remains mandatory.This article is protected by copyright. All rights reserved.
    Full-text · Article · May 2015 · European Journal of Clinical Investigation
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    ABSTRACT: The prostate-specific membrane antigen (PSMA) has recently emerged as a target for radionuclide imaging and therapy of prostate cancer [1, 2]. However, PSMA expression was also shown on the cell membrane of endothelial cells of tumour neovasculature in a number of other cancers such as renal cell carcinoma [3, 4], colon carcinoma, neuroendocrine tumours, melanoma or breast cancer [3]. However, to our knowledge no study has yet investigated the expression of PSMA in the neovasculature of differentiated thyroid cancer (DTC).[68Ga]PSMA-HBED-CC can be used for positron emission tomography (PET)/CT-based staging of prostate cancer [1] as well as for eligibility screening for and monitoring of PSMA-targeted radionuclide therapy [2].Considering the limited number of therapeutic options currently available for patients with metastasized, 131I-negative, [18F]-2-fluorodeoxyglucose-positive DTC [5], we hypothesized that PSMA expression could be present in DTC as well. This would provide an intere ...
    No preview · Article · Apr 2015 · European Journal of Nuclear Medicine
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    ABSTRACT: Many prognostic systems have been developed for differentiated thyroid cancer. It is unclear which one of these performs "best". Our aim was to compare staging systems applicable to our patient database to identify which best predicts DTC related loss of life expectancy and DTC specific mortality. Database study of DTC patients treated in our centre between 1978 (earliest available data) up to and including July 1, 2014. All were staged in accordance with the AMES, Clinical Class, Memorial Sloan Kettering, Ohio State University, TNM versions 5 and 6/7, University of Alabama, University of Münster and qTNM systems. 2257 differentiated thyroid cancer patients. loss of life expectancy expressed as relative survival and thyroid cancer specific mortality. Comparison was based on p values of univariate Cox regression analyses as well as analysis of the proportion of variance explained (PVE). Median available follow-up time was 7.2 years (range: 0-35.1 years). 327 patients died, 149 of whom died of DTC. Version 7 of the TNM system was best for predicting DTC related mortality (p=7.1*10(-52) ; PVE=0.296), followed by TNM version 5 (p=6.7*10(-44) ; PVE=0.255). For prediction of loss of life expectancy, version 7 of the TNM system was also best, closely followed by the Clinical Class system (p both < 2*10(-16) ). The UICC/AJCC TNM-system version 7 outperforms other prognostic classification systems based on extent of disease at the start of treatment both for prediction of differentiated thyroid cancer related death and for prediction of loss life expectancy. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
    No preview · Article · Mar 2015 · Clinical Endocrinology
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    ABSTRACT: Aim: To compare uptake measurements and different methods for the pretherapeutic determination of the effective thyroidal ¹³¹I half life (Teff) to the results of posttherapeutic dosimetric measurements. Patients, methods: Retrospective study of 1538 patients who received their first RIT in our department for autonomous thyroid nodules (ATN), autonomous multinodular goiter (AMG) or Graves' disease (GD) between November 1999 and January 2011. Pretherapeutic measurements were performed at any combination of 24 h, 48 h and 6 days after 131I administration. Post-therapy dosimetric measurements were performed in 12 h intervals until discharge. Teff was determined through monoexponential curve fitting. Results: Pretherapeutic Teff values based on measurements at 24 h and 48 h, 24 h and 6 d, 48 h and 6 d as well as on day 24 h, 48 h and 6 d yielded implausible (< 2 d or > 8 d) values for Teff, in 60.4%, 25.7%, 29.1 and 21.4% of available calculations, respectively. The plausible results showed significant, clinically relevant and sometimes considerable overestimations of Teff. Using empirically determined fixed disease specific Teff values resulted in a better congruence between the pre- and posttherapeutic dosimetry results. 24 h measurements were marginally more accurate than 48 h ones in AMG and GD whereas 48 h measurements were marginally more accurate in ATN; these differences are however not clinically relevant. 6 d measurements are clearly less accurate than those after 24 h or 48 h. Conclusion: In ATN, AMG and GD, pretherapeutic dosimetry can be performed by a single uptake measurement at 24 h or 48 h using a fixed, disease specific value for Teff. Additional later measurements do not yield a further clinically relevant contribution to accuracy of pretherapeutic dosimetry.
    No preview · Article · Dec 2014 · Nuklearmedizin
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    ABSTRACT: The aim of this study is to evaluate the impact of a high resolution (HR) image reconstruction with a voxel size of 2mm in comparison to the most routinely used standard reconstruction with 4mm voxels in patients suffering from prostate cancer having undergone (18)F-methylcholine PET/CT. Phantom studies were performed using a Jaszczak phantom and a custom made phantom containing small hot lesions (size 2-10mm). Clinical evaluation was performed on PET/CT scans of 50 patients. Images were reconstructed with 4mm and 2mm voxel size and analyzed quantitatively using AMIDE and MATLAB. Clinical images were judged by two observers concerning TNM staging, image quality and the correlation of PET and CT data. Phantom studies revealed increased SUVmean and SUVmax values in the HR images (P<0.01). The lower detection limit was approximately 3mm in the HR and 4-5mm in the conventional images. Lower FWHM values were found in the HR images. No significant difference was found concerning the image quality and the correlation of PET and CT (each P>0.5). For both reconstructions, a comparable total amount of lesions was reported (P>0.5) with no impact on the TNM staging. In conclusion, the HR PET reconstruction provides semi-quantitative advantages in the sense of an improved lower detection limit and increased semi-quantitative tumour-to-background ratios. In the setting of choline PET/CT for prostate cancer the high resolution reconstruction could be implemented clinically as there are no relevant qualitative differences between this and the conventional image resolution in terms of image quality, assessment confidence and lesion identification rate.
    No preview · Article · Nov 2014 · Hellenic journal of nuclear medicine
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    ABSTRACT: Abstract Differentiated thyroid cancer (DTC) is the most common endocrine cancer and its incidence has increased in recent decades. The initial treatment consists of total thyroidectomy followed by ablation of thyroid remnants by radioiodine in most cases. As thyroid cells are the only source of thyroglobulin (Tg), circulating Tg serves as a biochemical marker of persistent or recurrent disease in the follow-up of DTC. Due to the suboptimal clinical detection rate of older Tg assays endogenous or exogenous thyrotropin (TSH) stimulations are recommended for unmasking occult disease. However, the development of new Tg assays with improved analytical sensitivity and precision at low concentrations now allows detection of very low Tg concentrations, reflecting minimal amounts of thyroid tissue, even without the need for TSH stimulation. Even if the use of these assays still has not found its way in current clinical guidelines, such assays are now increasingly used in clinical practice. As serum Tg measurement is a technically challenging assay and criteria to define a 'highly sensitive' assay may be different, a good knowledge of the technical difficulties and interpretation criteria is of paramount importance for both clinical thyroidologists, laboratory physicians and scientists involved in the care of DTC patients.
    No preview · Article · Oct 2014 · Clinical Chemistry and Laboratory Medicine
  • Frederik A Verburg · Uwe Mäder · Christoph Reiners · Heribert Hänscheid
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    ABSTRACT: Context: Recent trial results have revived interest in low activity initial I-131 therapy (RIT) of differentiated thyroid cancer (DTC) Objective: compare different initial I-131 activities for outcome. Design: Database study Setting: University hospital Patients: 1298 (698 low risk, 434 high risk M0 and 136 M1) DTC patients, grouped according to ablation activity (I: ≤2000 MBq (54 mCi), II: 2000-3000 MBq (54-81 mCi) and III: >3000 MBq (81 mCi)), subdivided by age (<45 and ≥45 years at diagnosis). Main outcome measures: Complete remission (CR: Tg below functional sensitivity combined with visually negative I-131 diagnostic whole body scintigraphy), recurrence and DTC specific mortality rates, life expectancy. Results: Low risk patients: in patients <45 a lower median cumulative activity was required to achieve CR in group III (3590 MBq) than in groups I (8050 MBq) and II (6300 MBq). In patients ≥45 DTC specific mortality was significantly higher in group I than in groups II and III (15-year:16.1±7.7%, 0.8±0.8% and 7.2±5.5%, respectively; p=0.004). High risk M0 patients: In patients ≥45 the recurrence rate (15-year: 44.4±16.6%, 24.1±7.6% and 8.6±3.9%; p=0.001) and DTC specific mortality (15-year: 51.8±15.8%, 13.2±4.4% and 9.5±3.7%; p=0.004) were significantly higher in group I than in groups II and III. M1 patients: There were no significant differences in survival results between different activity groups in either age category. Conclusion: Before adopting low initial activity RIT for, especially older, low risk patients, results of long-term follow-up should be regarded critically. Low-activity RIT in older high-risk patients is not to be recommended.
    No preview · Article · Sep 2014 · Journal of Clinical Endocrinology & Metabolism
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    ABSTRACT: Purpose: To determine the frequency of seemingly pathological retroperitoneal uptake in the location of the coeliac ganglia in patients undergoing [(68)Ga]PSMA-HBED PET/CT. Methods: The study included 85 men with prostate cancer referred for [(68)Ga]PSMA-HBED PET/CT. The PET/CT scans were evaluated for the local finding in the prostate and the presence of lymph node metastases, distant metastases and coeliac ganglia. The corresponding standardized uptake values (SUV) were determined. SUVmax to background uptake (gluteal muscle SUVmean) ratios were calculated for the ganglia and lymph node metastases. Immunohistochemistry was performed on the ganglia. Results: In 76 of the 85 patients (89.4%) at least one ganglion with tracer uptake was found. For the ganglia, SUVmax and SUVmax to background SUVmean ratios were 2.97 ± 0.88 and 7.98 ± 2.84 (range 1.57-6.38 and 2.83-30.6), respectively, and 82.8% of all ganglia showed an uptake ratio of >5.0. For lymph node metastases, SUVmax and SUVmax to background SUVmean ratios were 8.5 ± 7.0 and 23.31 ± 22.23 (range 2.06-35.9 and 5.25-115.8), respectively. In 35 patients (41.2%), no lymph node metastases were found but tracer uptake was seen in the ganglia. Immunohistochemistry confirmed strong PSMA expression in the ganglia. Conclusion: Coeliac ganglia show a relevant [(68)Ga]PSMA-HBED uptake in most patients and may mimic lymph node metastases.
    No preview · Article · Sep 2014 · European journal of nuclear medicine and molecular imaging

Publication Stats

1k Citations
481.19 Total Impact Points

Institutions

  • 2011-2015
    • University Hospital RWTH Aachen
      • Department of Neurology
      Aachen, North Rhine-Westphalia, Germany
    • Maastricht University
      Maestricht, Limburg, Netherlands
    • RWTH Aachen University
      • Department of Nuclear Medicine
      Aachen, North Rhine-Westphalia, Germany
  • 2009-2015
    • University of Wuerzburg
      • Department of Nuclear Medicine
      Würzburg, Bavaria, Germany
    • Department of Nuclear Medicine
      Nyitra, Nitriansky, Slovakia
  • 2014
    • Universitätsklinikum Düsseldorf
      Düsseldorf, North Rhine-Westphalia, Germany
  • 2013
    • Maastricht Universitair Medisch Centrum
      Maestricht, Limburg, Netherlands
  • 2011-2012
    • Ente Ospedaliero Cantonale
      Bellinzona, Ticino, Switzerland
  • 2010
    • Universität Ulm
      • Clinic of Nuclear Medicine
      Ulm, Baden-Württemberg, Germany
  • 2009-2010
    • St. Antonius Ziekenhuis
      • Department of Nuclear Medicine
      Nieuwegen, Utrecht, Netherlands
  • 2004-2009
    • University Medical Center Utrecht
      Utrecht, Utrecht, Netherlands
  • 2005
    • Utrecht University
      Utrecht, Utrecht, Netherlands