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1.
Eur J Nucl Med Mol Imaging ; 51(4): 1121-1132, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37897617

RESUMO

PURPOSE: Peptide receptor radionuclide therapy (PRRT) using [177Lu]Lu-DOTATATE has been shown to effectively prolong progression free survival in grade 1-2 gastroenteropancreatic neuroendocrine tumours (GEP-NET), but is less efficacious in patients with extensive liver metastases. The aim was to investigate whether tumour uptake in liver metastases can be enhanced by intra-arterial administration of [177Lu]Lu-DOTATATE into the hepatic artery, in order to improve tumour response without increasing toxicity. METHODS: Twenty-seven patients with grade 1-2 GEP-NET, and bi-lobar liver metastases were randomized to receive intra-arterial PRRT in the left or right liver lobe for four consecutive cycles. The contralateral liver lobe and extrahepatic disease were treated via a "second-pass" effect and the contralateral lobe was used as the control lobe. Up to three metastases (> 3 cm) per liver lobe were identified as target lesions at baseline on contrast-enhanced CT. The primary endpoint was the tumour-to-non-tumour (T/N) uptake ratio on the 24 h post-treatment [177Lu]Lu-SPECT/CT after the first cycle. This was calculated for each target lesion in both lobes using the mean uptake. T/N ratios in both lobes were compared using paired-samples t-test. FINDINGS: After the first cycle, a non-significant difference in T/N uptake ratio was observed: T/NIA = 17·4 vs. T/Ncontrol = 16·2 (p = 0·299). The mean increase in T/N was 17% (1·17; 95% CI [1·00; 1·37]). Of all patients, 67% (18/27) showed any increase in T/N ratio after the first cycle. CONCLUSION: Intra-arterial [177Lu]Lu-DOTATATE is safe, but does not lead to a clinically significant increase in tumour uptake.


Assuntos
Neoplasias Hepáticas , Tumores Neuroendócrinos , Compostos Organometálicos , Humanos , Octreotida/efeitos adversos , Compostos Organometálicos/uso terapêutico , Neoplasias Hepáticas/radioterapia , Neoplasias Hepáticas/secundário , Tumores Neuroendócrinos/radioterapia , Tumores Neuroendócrinos/patologia , Radioisótopos
2.
EJNMMI Res ; 11(1): 73, 2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-34398356

RESUMO

BACKGROUND: Physiologically based pharmacokinetic (PBPK) models combine drug-specific information with prior knowledge on the physiology and biology at the organism level. Whole-body PBPK models contain an explicit representation of the organs and tissue and are a tool to predict pharmacokinetic behavior of drugs. The aim of this study was to develop a PBPK model to describe organ distribution of 68Ga-DOTATATE in a population of patients without detectable neuroendocrine tumors (NETs). METHODS: Clinical 68Ga-DOTATATE PET/CT data from 41 patients without any detectable somatostatin receptor (SSTR) overexpressing tumors were included. Scans were performed at 45 min (range 30-60 min) after intravenous bolus injection of 68Ga-DOTATATE. Organ (spleen, liver, thyroid) and blood activity levels were derived from PET scans, and corresponding DOTATATE concentrations were calculated. A whole-body PBPK model was developed, including an internalization reaction, receptor recycling, enzymatic reaction for intracellular degradation and renal clearance. SSTR2 expression was added for several organs. Input parameters were fixed or estimated using a built-in Monte Carlo algorithm for parameter identification. RESULTS: 68Ga-DOTATATE was administered with a median peptide amount of 12.3 µg (range 8.05-16.9 µg) labeled with 92.7 MBq (range 43.4-129.9 MBq). SSTR2 amounts for spleen, liver and thyroid were estimated at 4.40, 7.80 and 0.0108 nmol, respectively. Variability in observed organ concentrations was best described by variability in SSTR2 expression and differences in administered peptide amounts. CONCLUSIONS: To conclude, biodistribution of 68Ga-DOTATATE was described with a whole-body PBPK model, where tissue distribution was mainly determined by variability in SSTR2 organ expression and differences in administered peptide amounts.

3.
Artigo em Inglês | MEDLINE | ID: mdl-33740691

RESUMO

Lutetium-177 [177Lu] tetra-azacyclododecanetetra-acetic acid [DOTA]-(Tyr3)-octreotate [TATE] ([177Lu]Lu-DOTA-TATE) is a radiopeptide used for peptide receptor radionuclide therapy in patients with neuroendocrine tumours (NETs). This radiopeptide is made by labelling the ligand octreotate with Lutetium-177 using the linker DOTA. After labelling, and before clinical application quality control of the radiopeptide is needed and the radiochemical purity is assessed. Acceptance limits for radiochemical purity should be within 90-110% of the label claim for radiopharmaceuticals for diagnostic use and within 95-105% of the label claim for radiopharmaceuticals for therapeutic use. Moreover, the amount of unlabelled [177Lu]LuCl3 cannot exceed 2% of the radioactive dose. Since no monograph is available for [177Lu]Lu-DOTA-TATE in the European Pharmacopeia (Ph Eur), this article describes the development and validation of a high-performance liquid chromatography (HPLC) method with ultraviolet (UV) detection and radiodetection. A Waters Acquity Arc UHPLC system equipped with a Waters 2998 photodiode array (PDA) detector was used coupled to a Berthold Lb 514 Flowstar detector equipped with a BGO-X gamma measuring cell. A reversed phase Symmetry Shield C18 column (4.6 mm × 250 mm, 5 µm) was used for chromatographic separation. A flow of 1.5 mL/min was maintained during analysis, using 0.1% TFA in water as mobile phase A and 0.1% TFA in ACN as mobile phase B. The retention time was around 1.7 min and 13.5 min for [177Lu]LuCl3 and [177Lu]Lu-HA-DOTA-TATE, respectively. Stock solutions of [177Lu]LuCl3 were made by serial dilution and were injected to test for linearity, accuracy and precision, carry over and signal-to-noise ratio. A [177Lu]Lu-HA-DOTA-TATE sample was prepared and injected to determine the carry over. The results showed that the method is linear over a range of 0.300-130 MBq/mL, which covers the range for clinical samples, provided that the clinical sample is diluted ten times before analysis. The LLOQ can be measured accurately even after dilution, with a signal-to-noise ratio of at least 5. In short, the method is accurate, precise and sensitive and can be implemented as part of the quality control of [177Lu]Lu-HA-DOTA-TATE.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Octreotida/análogos & derivados , Compostos Organometálicos , Compostos Radiofarmacêuticos , Formas de Dosagem , Modelos Lineares , Octreotida/análise , Octreotida/química , Compostos Organometálicos/análise , Compostos Organometálicos/química , Compostos Radiofarmacêuticos/análise , Compostos Radiofarmacêuticos/química , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
4.
PLoS One ; 16(2): e0246394, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33529259

RESUMO

INTRODUCTION: Dynamic PET/CT allows visualization of pharmacokinetics over the time, in contrast to static whole body PET/CT. The objective of this study was to assess 68Ga-PSMA-11 uptake in pathological lesions and benign tissue, within 30 minutes after injection in primary prostate cancer (PCa) patients in test-retest setting. MATERIALS AND METHODS: Five patients, with biopsy proven PCa, were scanned dynamically in list mode for 30 minutes on a digital PET/CT-scanner directly after an intravenous bolus injection of 100 MBq 68Ga-PSMA-11. Approximately 45 minutes after injection a static whole body scan was acquired, followed by a one bed position scan of the pelvic region. The scans were repeated approximately four weeks later, without any intervention in between. Semi-quantitative assessment was performed using regions-of-interest in the prostate tumor, bladder, gluteal muscle and iliac artery. Time-activity curves were extracted from the counts in these regions and the intra-patient variability between both scans was assessed. RESULTS: The uptake of the iliac artery and gluteal muscle reached a plateau after 5 and 3 minutes, respectively. The population fell apart in two groups with respect to tumor uptake: in some patients the tumor uptake reached a plateau after 5 minutes, whereas in other patients the uptake kept increasing, which correlated with larger tumor volumes on PET/CT scan. Median intra-patient variation between both scans was 12.2% for artery, 9.7% for tumor, 32.7% for the bladder and 14.1% for the gluteal muscle. CONCLUSION: Dynamic 68Ga-PSMA-11 PET/CT scans, with a time interval of four weeks, are reproducible with a 10% variation in uptake in the primary prostate tumor. An uptake plateau was reached for the iliac artery and gluteal muscle within 5 minutes post-injection. A larger tumor volume seems to be related to continued tumor uptake. This information might be relevant for both response monitoring and PSMA-based radionuclide therapies.


Assuntos
Isótopos de Gálio/análise , Radioisótopos de Gálio/análise , Próstata/diagnóstico por imagem , Neoplasias da Próstata/diagnóstico por imagem , Idoso , Isótopos de Gálio/administração & dosagem , Isótopos de Gálio/farmacocinética , Radioisótopos de Gálio/administração & dosagem , Radioisótopos de Gálio/farmacocinética , Humanos , Masculino , Pelve/patologia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Próstata/patologia , Neoplasias da Próstata/patologia , Carga Tumoral
5.
EJNMMI Phys ; 6(1): 17, 2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31650365

RESUMO

BACKGROUND: Cerenkov Luminescence Imaging (CLI) is an emerging technology for intraoperative margin assessment. Previous research only evaluated radionuclide 18-Fluorine (18F); however, for future applications in prostate cancer, 68-Gallium (68Ga) seems more suitable, given its higher positron energy. Theoretical calculations predict that 68Ga should offer a higher signal-to-noise ratio than 18F; this is the first experimental confirmation. The aim of this study is to investigate the technical performance of CLI by comparing 68Ga to 18F. RESULTS: The linearity of the system, detection limit, spatial resolution, and uniformity were determined with the LightPath imaging system. All experiments were conducted with clinically relevant activity levels in vitro, using dedicated phantoms. For both radionuclides, a linear relationship between the activity concentration and detected light yield was observed (R2 = 0.99). 68Ga showed approximately 22 times more detectable Cerenkov signal compared to 18F. The detectable activity concentration after a 120 s exposure time and 2 × 2 binning of 18F was 23.7 kBq/mL and 1.2 kBq/mL for 68Ga. The spatial resolution was 1.31 mm for 18F and 1.40 mm for 68Ga. The coefficient of variance of the uniformity phantom was 0.07 for the central field of view. CONCLUSION: 68Ga was superior over 18F in terms of light yield and minimal detection limit. However, as could be expected, the resolution was 0.1 mm less for 68Ga. Given the clinical constraints of an acquisition time less than 120 s and a spatial resolution < 2 mm, CLI for intraoperative margin assessment using 68Ga could be feasible.

6.
Eur J Nucl Med Mol Imaging ; 46(3): 696-703, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30097670

RESUMO

INTRODUCTION: Somatostatin receptor imaging with PET is the standard of care for patients with a neuroendocrine tumour (NET). Since therapy and imaging with somatostatin analogues utilize the same receptor, current guidelines recommend withdrawing long-acting somatostatin analogues for 3-4 weeks prior to somatostatin receptor PET imaging. The aim of this study is to prospectively assess the effect of lanreotide use on the uptake of 68Ga-DOTATATE intra-individually 1 day prior to and 1 day post injection of lanreotide. METHODS: Thirty-four patients with metastatic and/or unresectable NET and currently on lanreotide therapy for at least 4 months were included in the study. A 68Ga-DOTATATE PET/CT scan was performed on the day before and the day after lanreotide injection. In each patient 68Ga-DOTATATE uptake (SUVmax, mean, peak) was assessed in both tumour lesions and normal tissue. All scans were assessed by two blinded nuclear medicine physicians for visual analysis. Paired T-tests were performed to determine the differences between the scans. RESULTS: Of the 34 patients included, 31 were available for analyses in which 190 tumour lesions were measured. Uptake of 68Ga-DOTATATE in tumour lesions was increased significantly after lanreotide, but decreased significantly in the liver, spleen, and thyroid gland resulting in a higher tumour-to-liver ratio. CONCLUSION: Lanreotide injection prior to 68Ga-DOTATATE PET/CT does not result in decreased tumour uptake. In contrast, tumour uptake was increased, whereas the uptake in normal organs is decreased, leading to an increased tumour-to-liver ratio. However, these differences were small and not deemed clinically relevant. These results strongly suggest that discontinuation of lanreotide injections in the weeks prior to 68Ga-DOTATATE PET examinations is unnecessary and does not compromise nuclear medicine imaging results.


Assuntos
Tumores Neuroendócrinos/metabolismo , Compostos Organometálicos/metabolismo , Peptídeos Cíclicos/farmacologia , Somatostatina/análogos & derivados , Idoso , Transporte Biológico/efeitos dos fármacos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tumores Neuroendócrinos/diagnóstico por imagem , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Estudos Prospectivos , Receptores de Somatostatina/metabolismo , Somatostatina/farmacologia
7.
Eur J Nucl Med Mol Imaging ; 44(7): 1165-1175, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28180965

RESUMO

PURPOSE: Recurrent disease following thermal ablation therapy is a frequently reported problem. Preoperative identification of patients with high risk of recurrent disease might enable individualized treatment based on patients' risk profile. The aim of the present work was to investigate the role of metabolic parameters derived from the pre-ablation 18F-FDG PET/CT as imaging biomarkers for recurrent disease in patients with colorectal liver metastases (CLM). METHODS: Included in this retrospective study were all consecutive patients with CLM treated with percutaneous or open thermal ablation therapy who had a pre-treatment baseline 18F-FDG PET/CT available. Multivariable cox regression for survival analysis was performed using different models for the metabolic parameters (SULpeak, SULmean, SULmax, partial volume corrected SULmean (cSULmean), and total lesion glycolysis (TLG)) corrected for tumour and procedure characteristics. The study endpoints were defined as local tumour progression free survival (LTP-FS), new intrahepatic recurrence free survival (NHR-FS) and extrahepatic recurrence free survival (EHR-FS). Clinical and imaging follow-up data was used as the reference standard. RESULTS: Fifty-four patients with 90 lesions were selected. Univariable cox regression analysis resulted in eight models. Multivariable analysis revealed that after adjusting for lesion size and the approach of the procedure, none of the metabolic parameters were associated with LTP-FS or EHR-FS. Percutaneous approach was significantly associated with a shorter LTP-FS. It was demonstrated that lower values of SULpeak, SULmax, SULmean , and cSULmean are associated with a significant better NHR-FS, independent of the lesion size and number and prior chemotherapy. CONCLUSION: We found no association between the metabolic parameters on pre-ablation 18F-FDG PET/CT and the LTP-FS. However, low values of the metabolic parameters were significantly associated with improved NHR-FS. The clinical implication of these findings might be the identification of high-risk patients who might benefit most from adjuvant or combined treatment strategies.


Assuntos
Técnicas de Ablação , Neoplasias Colorretais/patologia , Progressão da Doença , Fluordesoxiglucose F18 , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/secundário , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/metabolismo , Feminino , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/terapia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
8.
Rev Esp Med Nucl Imagen Mol ; 36(3): 158-165, 2017.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-28038997

RESUMO

PURPOSE: To assess the 3D geometric sampling accuracy of a new PET-guided system for breast cancer biopsy (BCB) from areas within the tumour with high 18F-FDG uptake. MATERIALS AND METHODS: In the context of the European Union project MammoCare, a prototype semi-robotic stereotactic prototype BCB-device was incorporated into a dedicated high resolution PET-detector for breast imaging. The system consists of 2 stacked rings, each containing 12 plane detectors, forming a dodecagon with a 186mm aperture for 3D reconstruction (1mm3 voxel). A vacuum-assisted biopsy needle attached to a robot-controlled arm was used. To test the accuracy of needle placement, the needle tip was labelled with 18F-FDG and positioned at 78 target coordinates distributed over a 35mm×24mm×28mm volume within the PET-detector field-of-view. At each position images were acquired from which the needle positioning accuracy was calculated. Additionally, phantom-based biopsy proofs, as well as MammoCare images of 5 breast cancer patients, were evaluated for the 3D automated locating of 18F-FDG uptake areas within the tumour. RESULTS: Needle positioning tests revealed an average accuracy of 0.5mm (range 0-1mm), 0.6mm (range 0-2mm), and 0.4mm (range 0-2mm) for the x/y/z-axes, respectively. Furthermore, the MammoCare system was able to visualize and locate small (<10mm) regions with high 18F-FDG uptake within the tumour suitable for PET-guided biopsy after being located by the 3D automated application. CONCLUSIONS: Accuracy testing demonstrated high-precision of this semi-automatic 3D PET-guided system for breast cancer core needle biopsy. Its clinical feasibility evaluation in breast cancer patients scheduled for neo-adjuvant chemotherapy will follow.


Assuntos
Neoplasias da Mama/patologia , Mama/patologia , Fluordesoxiglucose F18 , Compostos Radiofarmacêuticos , Biópsia por Agulha/instrumentação , Desenho de Equipamento , Feminino , Humanos , Biópsia Guiada por Imagem/instrumentação , Procedimentos Cirúrgicos Robóticos
9.
Eur J Surg Oncol ; 43(4): 625-635, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27847287

RESUMO

INTRODUCTION: 18F-FDG PET/CT has high positive predictive value for the detection of avid lymph node metastases in breast cancer patients. We analysed the effect of upstaging lymph nodes by PET/CT on short-term outcome in stage II/III breast cancer patients. PATIENTS AND METHODS: A total of 278 stage II/III primary breast cancer patients (mean age 48.9 years, range 19-75 years) were re-staged with 18F-FDG PET/CT before start of pre-operative systemic treatment (PST). Patients were divided in three groups based on risk for local recurrence: a low - (T2N0), intermediate - (T0-2N1 and T3N0) and a high-risk group (T0-3N2-3, T3N1 and T4). Within these groups we looked at local recurrence-free survival (LRFS), recurrence-free survival (RFS) and overall survival (OS) within the first 3 years of follow-up. RESULTS: With a median follow-up (FU) of 50 months the RFS, LRFS and OS were 87%, 88% and 92% respectively for the whole group. PET/CT upstaged 43 patients from the low- and intermediate risk group to the high-risk group, based on detection of ≥4 avid axillary nodes or occult N2/3-disease. Patients upstaged with PET/CT had more events for all three analyses compared to the original risk groups, which resulted in a significantly worse RFS (69.8%; p = 0.03) a nearly significantly worse LRFS (p = 0.052) and no effect in OS (p = 0.433). DISCUSSION: Additional PET/CT staging allows breast cancer patients to be treated according to the true stage, still stage II/III breast cancer patients upstaged to N2/3 by PET/CT have worse short-term outcome, despite adjustment of treatment, than patients staged high-risk with conventional imaging.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Carcinoma Ductal de Mama/tratamento farmacológico , Carcinoma Lobular/tratamento farmacológico , Adulto , Idoso , Axila , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Carboplatina/administração & dosagem , Carcinoma Ductal de Mama/diagnóstico por imagem , Carcinoma Ductal de Mama/patologia , Carcinoma Lobular/diagnóstico por imagem , Carcinoma Lobular/patologia , Ciclofosfamida/administração & dosagem , Intervalo Livre de Doença , Doxorrubicina/administração & dosagem , Feminino , Fluordesoxiglucose F18 , Humanos , Linfonodos/patologia , Metástase Linfática , Pessoa de Meia-Idade , Terapia Neoadjuvante , Estadiamento de Neoplasias , Paclitaxel/administração & dosagem , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Prognóstico , Compostos Radiofarmacêuticos , Trastuzumab/administração & dosagem , Adulto Jovem
10.
Eur J Surg Oncol ; 42(4): 497-503, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26847531

RESUMO

INTRODUCTION: Lymphoscintigraphy with planar imaging is considered a helpful tool to depict lymph node drainage in patients with invasive breast cancer. Single Photon Emission Computed Tomography with integrated CT (SPECT/CT) is usually performed to detect sentinel nodes (SN)s in breast cancer patients showing non-visualisation on lymphoscintigraphy. Incorporation of new SN indications (recurrent surgery, previous radiotherapy, or neo-adjuvant chemotherapy) has led to an increase of non-visualisation rates. The present study evaluates the contribution of SPECT/CT and tracer reinjection for SN-visualisation in breast cancer patients without drainage on lymphoscintigraphy. METHODS: Between 1st of July 2008 and 6th of November 2014 in total 1968 patients underwent a SN breast procedure, using intra-tumoural tracer administration. SPECT/CT was performed in 284 breast cancer patients with non-visualisation of SNs on lymphoscintigraphy. If SN non-visualisation persisted, a second radiotracer injection with repeated imaging was performed when logistics allowed this. Univariate analysis was applied to evaluate SPECT/CT visualisation rates in specific subgroups. RESULTS: The SPECT/CT visualisation rate was 23.2% (66/284). Univariate analysis revealed no significant subgroups influencing SPECT/CT visualisation. In patients receiving reinjection after persistent SPECT/CT non-visualisation the SN-visualisation rate reached 62.1% (36/58). Intraoperatively, the SN-identification rate using a gamma probe and blue dye was 87.9% (175/199) and 32.9% (28/85) for, respectively, primary and recurrent surgery after non-visualisation on lymphoscintigraphy. CONCLUSION: In this evaluation including new breast cancer SN indications, SPECT/CT scored lower than reinjection to visualise SNs in patients with non-visualisation on lymphoscintigraphy. Consequently, our institutional protocol has been readjusted.


Assuntos
Neoplasias da Mama/diagnóstico , Meios de Contraste/administração & dosagem , Biópsia de Linfonodo Sentinela , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Tomografia Computadorizada por Raios X/métodos , Neoplasias da Mama/secundário , Feminino , Seguimentos , Humanos , Injeções Intralesionais , Metástase Linfática , Pessoa de Meia-Idade , Estudos Retrospectivos
11.
Eur J Endocrinol ; 164(4): 475-83, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21257726

RESUMO

OBJECTIVE: To establish the prevalence of osteoporosis, vertebral fractures (VFs), and non-VFs in acromegaly patients with long-term controlled disease and factors potentially influencing fracture risk. DESIGN: Case-control study. Patients and measurements Eighty-nine patients (46% male, mean age: 58 years) were included. We studied VFs and non-VFs, bone mineral density (BMD), and markers of bone turnover. In 48 patients, BMD assessment was also obtained 7 years prior to the current study. To compare VF prevalence, data from a sample of the Dutch population (n=3469) were used. RESULTS: VF prevalence was 59% (men 64% and women 54%), significantly increased when compared with controls (odds ratio up to 6.5), and independent of the duration of disease control, BMD, markers of bone turnover, and acromegalic disease characteristics. Mean number of VFs per patient was 3.4±0.3 (range 1-8). There was no relationship between the number and severity of fractures, parameters of bone turnover, and follow-up BMD measurements. BMD did not change during prolongation of follow-up by 7 years of controlled acromegaly. CONCLUSION: There is a very high prevalence of VFs in acromegaly patients with long-term controlled disease, independently of BMD. In view of the significant morbidity and mortality associated with VFs in general and the inability of BMD to predict fracture risk in acromegalic patients, we propose to include VF assessment, for example by lateral conventional radiographs of the spine in the screening of patients with acromegaly, both at diagnosis and during follow-up after establishment of disease control.


Assuntos
Acromegalia/complicações , Densidade Óssea/fisiologia , Fraturas da Coluna Vertebral/epidemiologia , Fraturas da Coluna Vertebral/etiologia , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
12.
J Nucl Cardiol ; 17(2): 207-15, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20035391

RESUMO

BACKGROUND: Elevated transient ischemic dilatation (TID) ratio during myocardial perfusion imaging (MPI) is described as a marker of severe CAD, even in acquisitions with normal perfusion. This was initiated to explore the effects of stressor type on the TID. Additionally the relation between the TID and other functional parameters, such as end diastolic volume (EDV), end systolic volume (ESV), and left ventricle ejection fraction (LVEF), heart rate (HR), and severity of ischemia, was evaluated. METHOD: A total of 299 consecutive patients referred for a 2-day stress/rest MPI protocol were included. Patients were stressed with either adenosine (n = 164) or exercise (n = 135). MPI data were analyzed with an automated software tool to determine TID, EDV, ESV, LVEF, SSS, and SDS. The SDS was used to quantify the degree of ischemia, with a SDS > or = 3 considered ischemic. RESULTS: Comparison of the adenosine and exercise stressed population revealed significant differences, especially in parameters derived from the poststress acquisition. Within the exercise stressed population, TID was proportional with the SDS (R(2) = .12); whereas the adenosine population did not show such a relation (R(2) = .001). Difference in HR between rest and poststress acquisitions showed high levels of linear regression with TID values of both the adenosine (R(2) = .41) and exercise (R(2) = .29) stressed population. CONCLUSION: In an exercise stressed population, TID is determined by both the degree of ischemia and the heart-rate difference between the two acquisition moments. TID within the adenosine population was found to be highly proportional with the HR, rather than with the degree of ischemia.


Assuntos
Coração/diagnóstico por imagem , Isquemia Miocárdica , Cintilografia/métodos , Adenosina/metabolismo , Idoso , Automação , Doença da Artéria Coronariana/diagnóstico por imagem , Exercício Físico , Feminino , Frequência Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade , Compostos Organofosforados/química , Compostos de Organotecnécio/química , Perfusão , Estudos Retrospectivos , Função Ventricular Esquerda
13.
Eur J Endocrinol ; 161(5): 771-7, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19671708

RESUMO

BACKGROUND: Despite the long experience with radioiodine for hyperthyroidism, controversy remains regarding the optimal method to determine the activity that is required to achieve long-term euthyroidism. OBJECTIVES: To compare the effect of estimated versus calculated activity of radioiodine in hyperthyroidism. Design Systematic review and meta-analysis. METHODS: We searched the databases Medline, EMBASE, Web of Science, and Cochrane Library for randomized and nonrandomized studies, comparing the effect of activity estimation methods with dosimetry for hyperthyroidism. The main outcome measure was the frequency of treatment success, defined as persistent euthyroidism after radioiodine treatment at the end of follow-up in the dose estimated and calculated dosimetry group. Furthermore, we assessed the cure rates of hyperthyroidism. RESULTS: Three randomized and five nonrandomized studies, comparing the effect of estimated versus calculated activity of radioiodine on clinical outcomes for the treatment of hyperthyroidism, were included. The weighted mean relative frequency of successful treatment outcome (euthyroidism) was 1.03 (95% confidence interval (CI) 0.91-1.16) for estimated versus calculated activity; the weighted mean relative frequency of cure of hyperthyroidism (eu- or hypothyroidism) was 1.03 (95% CI 0.96-1.10). Subgroup analysis showed a relative frequency of euthyroidism of 1.03 (95% CI 0.84-1.26) for Graves' disease and of 1.05 (95% CI 0.91-1.19) for toxic multinodular goiter. CONCLUSION: The two main methods used to determine the activity in the treatment of hyperthyroidism with radioiodine, estimated and calculated, resulted in an equally successful treatment outcome. However, the heterogeneity of the included studies is a strong limitation that prevents a definitive conclusion from this meta-analysis.


Assuntos
Hipertireoidismo/radioterapia , Radioisótopos do Iodo/administração & dosagem , Relação Dose-Resposta à Radiação , Humanos , Dosagem Radioterapêutica , Resultado do Tratamento
14.
Nuklearmedizin ; 48(4): 138-42; quiz N19-20, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19384451

RESUMO

OBJECTIVE: Dosimetry studies have shown that activities of 131I as small as 10-20 MBq may cause a stunning effect. A result of this stunning effect may be a lower success rate of the ablative 131I therapy for differentiated thyroid carcinoma (DTC). The aim of this study was to determine whether pre-therapeutic uptake measurement with 40 MBq 131I causes a lower success rate of ablation. DESIGN: retrospective chart review study. PATIENTS, METHODS: In two hospitals the ablation protocols differed in one respect only: in the one hospital no diagnostic 131I was applied before ablation (group 1, n = 48), whereas in the other hospital a 24-h uptake-measurement with 40 MBq 131I was performed (group 2, n = 51). Included were all DTC patients without distant metastases who had undergone 131I ablation between July 2002 and December 2005, and who had returned for 131I follow-up. Successful ablation was defined as absence of pathological 131I uptake on diagnostic whole-body scintigraphy and undetectable thyroglobulin-levels under TSH stimulation. RESULTS: Overall, ablation was successful in 31/48 patients (65%) in group 1 and in 17/51 patients (33%) in group 2 (p=0.002). Multivariate analysis showed that pre-therapeutic uptake measurement using 40 MBq 131I was an independent determinant for success of ablation (p = 0.002). CONCLUSIONS: After applying a diagnostic activity of 40 MBq 131I before ablation, the success rate of ablation is severely reduced. Consequently, the routine application of 131I for diagnostic scintigraphy or uptake measurement prior to 131I ablation is best avoided.


Assuntos
Radioisótopos do Iodo/uso terapêutico , Neoplasias da Glândula Tireoide/radioterapia , Feminino , Seguimentos , Humanos , Metástase Linfática , Masculino , Invasividade Neoplásica , Compostos Radiofarmacêuticos/uso terapêutico , Dosagem Radioterapêutica , Neoplasias da Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/cirurgia , Tireoidectomia , Resultado do Tratamento
16.
Ned Tijdschr Geneeskd ; 150(27): 1523-7, 2006 Jul 08.
Artigo em Holandês | MEDLINE | ID: mdl-16892617

RESUMO

For a 74-year-old man with angina pectoris and demonstrated myocardial ischaemia, optimal medical treatment was insufficient. He was ineligible for coronary revascularization. To improve myocardial perfusion, autologous bone-marrow stem cells were injected into the ischaemic myocardium. During the months following the injection, the frequency of angina attacks decreased and myocardial perfusion and cardiac function improved.


Assuntos
Angina Pectoris/terapia , Transplante de Medula Óssea , Isquemia Miocárdica/terapia , Idoso , Circulação Coronária/fisiologia , Humanos , Masculino , Transplante Autólogo , Resultado do Tratamento
17.
Clin Endocrinol (Oxf) ; 64(6): 617-24, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16712662

RESUMO

OBJECTIVE: Lithium has been reported to increase radioactive iodine (RaI) doses in benign thyroid disease and in differentiated thyroid carcinoma (DTC). It is not known whether lithium influences the outcome of RaI therapy in DTC. We therefore studied the clinical effects of RaI without and with lithium carbonate in patients with proven metastatic DTC. Controversy also exists on the mechanism by which lithium increases RaI dose in DTC. We performed an in vitro study specifically aimed at examining the effects of lithium on the sodium iodide symporter (NIS). DESIGN: In a clinical study, 12 patients were selected with metastases of DTC who had received previous RaI therapy without lithium (control) that had not influenced tumour progression, despite RaI accumulation in metastases. The patients received 1200 mg lithium carbonate/day followed by 6000 MBq RaI. Outcome parameters were RaI uptake, serum thyroglobulin (Tg) levels and radiological dimensions of metastases compared between RaI with lithium and control. In an in vitro study, iodide uptake was studied in the benign rat thyroid cell line FRTL-5, in the polarized non-thyroid MDCK cell line, stably transfected with human sodium iodide symporter (hNIS) to study the effects of lithium on NIS in a non-thyroid background, and the human follicular thyroid carcinoma cell line FTC133-hNIS to study lithium effects in a background of DTC. Lithium chloride (LiCl) was added in concentrations up to 2 mM for 0-48 h. Both steady-state iodide uptake (30 min) and initial rate (2 min) were studied using a specific activity of 100 mCi/mmol I, the latter experiment to determine lithium effects on substrate dependency. Iodide efflux studies were performed as well. RESULTS: Despite an increased uptake of RaI in seven patients, no beneficial effect of RaI with lithium was observed on the clinical course as assessed by serum Tg measurements and radiographically. In the in vitro studies, no effects of LiCl on iodide uptake or efflux were observed. CONCLUSIONS: The addition of lithium to RaI did not have any beneficial effects on the clinical course in 12 patients with metastatic DTC. No beneficial effects of lithium on iodide uptake were observed in vitro. Therefore, the clinical value of lithium in DTC remains subject to debate.


Assuntos
Antitireóideos/uso terapêutico , Carcinoma Papilar/tratamento farmacológico , Radioisótopos do Iodo/uso terapêutico , Carbonato de Lítio/uso terapêutico , Neoplasias da Glândula Tireoide/tratamento farmacológico , Adjuvantes Farmacêuticos/uso terapêutico , Idoso , Animais , Carcinoma Papilar/metabolismo , Carcinoma Papilar/radioterapia , Carcinoma Papilar, Variante Folicular/tratamento farmacológico , Carcinoma Papilar, Variante Folicular/metabolismo , Carcinoma Papilar, Variante Folicular/radioterapia , Linhagem Celular , Linhagem Celular Tumoral , Feminino , Humanos , Radioisótopos do Iodo/metabolismo , Masculino , Pessoa de Meia-Idade , Ratos , Simportadores/genética , Simportadores/metabolismo , Glândula Tireoide/metabolismo , Neoplasias da Glândula Tireoide/metabolismo , Neoplasias da Glândula Tireoide/radioterapia , Transfecção/métodos , Falha de Tratamento
18.
Q J Nucl Med Mol Imaging ; 50(1): 78-87, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16557207

RESUMO

Well differentiated (follicular and papillary) thyroid cancer (DTC) is characterized by rare occurrence and a good prognosis. However, up to 20% of patients with DTC develop locoregional recurrences, whereas even 8% of patients with such recurrences will eventually die from disease. In some of these patients it is related to incomplete initial treatment, whereas in others it indicates the presence of an aggressive tumor. In this latter case, dedifferentiation may occur with negative I-131 whole body scintigraphy (WBS) results and unreliable Tg measurements. In patients with thyroid cancer metastases that lost the capability of I-131 uptake, other imaging techniques are required to depict the non-functioning metastases, irrespective of the Tg-levels and irrespective of the site of recurrent disease. In this respect, some reports have discussed the value of ultrasonography of the head and neck region with good results for the detection of locoregional disease. We have assessed the role of FDG-PET in patients with I-131 negative WBS and its relation with Tg values and TSH-stimulation based on data that have appeared in the literature. In this review article, a discussion is given on the results published so far.


Assuntos
Fluordesoxiglucose F18 , Tomografia por Emissão de Pósitrons/métodos , Tomografia por Emissão de Pósitrons/estatística & dados numéricos , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Neoplasias da Glândula Tireoide/epidemiologia , Ensaios Clínicos como Assunto , Humanos , Guias de Prática Clínica como Assunto , Padrões de Prática Médica/estatística & dados numéricos , Compostos Radiofarmacêuticos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
19.
Eur J Endocrinol ; 152(1): 87-94, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15762191

RESUMO

OBJECTIVE: The aim of this study was to identify the prevalence of catecholamine excess and phaeochromocytomas in a well-defined population of people with hereditary head and neck paragangliomas. METHODS: We studied in a prospective follow-up protocol all consecutive patients referred to the Department of Endocrinology, Leiden University Medical Center, Leiden, The Netherlands with documented head and neck paragangliomas and either a positive family history for paragangliomas or a proven SDHD gene mutation. Initial analysis included medical history, physical examination and the measurement of excretion of catecholamines in two 24-h urine collections. In the case of documented catecholamine excess iodinated meta-iodobenzylguanidine (123I-MIBG) scintigraphy and magnetic resonance imaging were done. RESULTS: Between 1988 and 2003, 40 consecutive patients (20 male and 20 female) with documented head and neck paragangliomas were screened. Biochemical screening revealed urinary catecholamine excess in 15 patients (37.5%). In nine of these 15 patients a lesion was found by 123I-MIBG scintigraphy. Exact localization by magnetic resonance imaging revealed phaeochromocytomas in seven of the 15 patients. One of the nine patients had an extra-adrenal paraganglioma. Histopathological examination in a subset of tumors displayed loss of heterozygosity of the wild-type SDHD allele in all cases. CONCLUSIONS: The prevalence of catecholamine excess (37.5%) and phaeochromocytomas (20.0%) is high in patients with familial head and neck paragangliomas. Therefore, patients with hereditary head and neck paragangliomas require lifelong follow up by biochemical testing for catecholamine excess.


Assuntos
Neoplasias das Glândulas Suprarrenais/urina , Catecolaminas/urina , Neoplasias de Cabeça e Pescoço/urina , Proteínas de Membrana/genética , Paraganglioma/urina , Feocromocitoma/urina , Neoplasias das Glândulas Suprarrenais/genética , Neoplasias das Glândulas Suprarrenais/metabolismo , Adulto , Estudos de Coortes , DNA de Neoplasias/genética , Feminino , Mutação em Linhagem Germinativa , Neoplasias de Cabeça e Pescoço/genética , Humanos , Imidazóis , Perda de Heterozigosidade/genética , Masculino , Pessoa de Meia-Idade , Paraganglioma/genética , Feocromocitoma/genética , Estudos Prospectivos , Succinato Desidrogenase
20.
Acta Paediatr ; 93(10): 1403-5, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15499966

RESUMO

UNLABELLED: A male newborn presented with congenital chylous ascites, the treatment of which is difficult and complicated due to persistent loss of chyle. The primary therapeutic goal is to reduce the lymph flow and to allow the leakage to heal naturally. Usually, conservative management--enteric rest with total parental feeding or an enteral diet with medium-chain triglycerides--can achieve this. A new treatment option is the use of octeotride, a somatostatin analogue. Both therapies failed in our patient, and surgical ligation of the leaking lymphatic duct was successful. CONCLUSION: The success of the surgical treatment depends on localizing the leaking lymphatic duct. Lymphatic imaging with lymphoscintigraphy and pre-operative administration of lipophilic dye can assist the surgeon.


Assuntos
Ascite Quilosa/congênito , Ascite Quilosa/terapia , Humanos , Recém-Nascido , Masculino
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