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PubMed | University of Belgrade, Ascend Technologies Ltd and Institute of Nuclear Medicine with Center
Type: Journal Article | Journal: Asia Oceania journal of nuclear medicine & biology | Year: 2016

The objectives of this work was to assess the benefits of the application of Physiologically Based Pharmacokinetic (PBPK) models in patients with different neuroendocrine tumours (NET) who were treated with Lu-177 DOTATATE. The model utilises clinical data on biodistribution of radiolabeled peptides (RLPs) obtained by whole body scintigraphy (WBS) of the patients.The blood flow restricted (perfusion rate limited) type of the PBPK model for biodistribution of radiolabeled peptides (RLPs) in individual human organs is based on the multi-compartment approach, which takes into account the main physiological processes in the organism: absorption, distribution, metabolism and excretion (ADME). The approach calibrates the PBPK model for each patient in order to increase the accuracy of the dose estimation. Datasets obtained using WBS in four patients have been used to obtain the unknown model parameters. The scintigraphic data were acquired using a double head gamma camera in patients with different neuroendocrine tumours who were treated with Lu-177 DOTATATE. The activity administered to each patient was 7400 MBq.Satisfactory agreement of the model predictions with the data obtained from the WBS for each patient has been achieved.The study indicates that the PBPK model can be used for more accurate calculation of biodistribution and absorbed doses in patients. This approach is the first attempt of utilizing scintigraphic data in PBPK models, which was obtained during Lu-177 peptide therapy of patients with NET.


Grubmuller B.,Medical University of Vienna | Baum R.P.,Center for Molecular Radiotherapy and Molecular Imaging | Capasso E.,Regional Oncological Hospital | Singh A.,Center for Molecular Radiotherapy and Molecular Imaging | And 9 more authors.
Cancer Biotherapy and Radiopharmaceuticals | Year: 2016

Aim: The prostate-specific membrane antigen (PSMA) is a cell surface protein, which is overexpressed in nearly all cases of prostate cancer (PCa). PET imaging with 68Ga-PSMA-HBED-CC has recently found widespread application in the diagnosis of recurrent PCa. In this study, the diagnostic potential of 64Cu-labeled PSMA ligand (PSMA-617) PET in patients with PCa has been investigated. Materials and Methods: The study was conducted simultaneously at two nuclear medicine centers, Austria (Vienna, Center 1) and Germany (Bad Berka, Center 2). The patients (n = 29) included in this study were referred for PET (Center 1, 21 patients) or PET/CT (Center 2, 8 patients) imaging with either a high suspicion of recurrent disease or for possible surgical or PSMA radioligand therapy planning. PET images of the whole body were performed at 1 hour p.i. and additional images of the pelvis at 2 hours p.i. Results: In 23 of 29 patients, at least one focus of pathological tracer uptake suspicious for primary disease in the prostate lobe or recurrent disease was detected. Among healthy organs, the salivary glands, kidneys, and liver showed the highest radiotracer uptake. Lesions suspicious for PCa were detected with excellent contrast as early as 1 hour p.i. with high detection rates even at low prostate-specific antigen (PSA) levels. Conclusion: The preliminary results of this study demonstrate the high potential of 64Cu-PSMA ligand PET/CT imaging in patients with recurrent disease and in the primary staging of selected patients with progressive local disease. The acquired PET images showed an excellent resolution of the detected lesions with very high lesion-to-background contrast. Furthermore, the long half-life of 64Cu allows distribution of the tracer to clinical PET centers that lack radiochemistry facilities for the preparation of 68Ga-PSMA ligand (satellite concept). © 2016 Mary Ann Liebert, Inc.


Pestitschek M.,Institute of Nuclear Medicine with Center | Pestitschek M.,University of Vienna | Sonneck-Koenne C.,Institute of Nuclear Medicine with Center | Zakavi S.R.,Mashhad University of Medical Sciences | And 3 more authors.
Wiener Klinische Wochenschrift | Year: 2013

The present study was undertaken to estimate the selenium intake of thyroid patients and investigate the possible relation between thyroid abnormalities and the selenium intake. Methods The selenium intake through foods and the nutritional habits of thyroid patients in general were analyzed. Total 212 subjects from thyroid outpatient clinic of two state hospitals were interviewed. Among 212 subjects, 21 had no thyroid abnormality and served as controls. A food frequency questionnaire (FFQ) was developed to define the individual selenium intakes. From five different food groups, a total of 15 selenium-rich foods were selected, which are obtainable in Austria. The clinical and nutritional data were analyzed. Results Animal products such as milk and meat (pork, beef and poultry) played the most important role for the selenium supply in the Austrian diet. The intake of selenium in 86 % of the total study population was below the estimated average requirement (EAR). The selenium level was higher in euthyroid people compared with hypothyroid patients. Conclusions The developed FFQ is a tool to estimate the selenium intake in individuals, as it could be shown in this study. A significant positive correlation between selenium intake and blood selenium level was noted. These results must be confirmed by further studies in larger patient population.


Mirzaei S.,Institute of Nuclear Medicine with Center | Bastati B.,Institute of Nuclear Medicine with Center | Lipp R.W.,Medical University of Graz | Knoll P.,Institute of Nuclear Medicine with Center | And 2 more authors.
Oncology | Year: 2011

Objective: Peptide receptor-targeted radionuclide therapy (PRRT) of somatostatin receptor (SR)-expressing neuroendocrine tumors (NETs) has become an established therapeutic option in patients with advanced NETs. The aim of this study was to compare the lesion detection rate of 99mTc-EDDA/HYNIC- TOC, a newly developed tracer for NET imaging, with 177Lu-DOTATATE used for PRRT. Methods: 8 patients (4 women, 4 men, age range 46-76 years) with histologically proven NETs, who showed high SR loads by 99mTc-EDDA/ HYNIC-TOC scintigraphy, were treated with 177Lu-DOTATATE. After treatment, all patients were subjected to whole-body scintigraphy with additional low-dose single-photon emission computed tomography (SPECT-CT) of the chest and abdomen. Results: All patients demonstrated 177Lu-DOTATATE accumulation in all lesions previously detected by 99mTc- EDDA/HYNIC-TOC scintigraphy. Three patients showed additional lesions in the liver and lungs. Conclusions: SPECT-CT after 177Lu-DOTATATE therapy may be helpful in detecting additional lesions not seen using 99mTc-EDDA/HYNIC-TOC. This could reflect the broader affinity of 177Lu-DOTATATE for SRs compared with 99mTc-EDDA/HYNIC-TOC. Copyright © 2011 S. Karger AG, Basel.


Ahmadzadehfar H.,Institute of Nuclear Medicine with Center | Rodrigues M.,Institute of Nuclear Medicine with Center | Zakavi R.,Mashhad University of Medical Sciences | Knoll P.,Institute of Nuclear Medicine with Center | Mirzaei S.,Institute of Nuclear Medicine with Center
Medical Oncology | Year: 2011

Metabolic imaging with F-18-fluorodeoxyglucose ( 18F-FDG) positron-emission tomography (PET) is widely used for staging and treatment evaluation of malignant lymphoma. To date, only a few studies have indicated that lower glucose metabolism measured by 18F-FDG PET before or early in the course of treatment of malignant lymphoma is associated with a favorable outcome. The aim of this study was to assess the prognostic capability of the 18F-FDG PET maximum standardized uptake value (SUV max), a semiquantitative measurement of glucose metabolism, at the time of diagnosis of malignant lymphoma. We retrospectively analyzed data from 69 patients (median age: 61 and range 23-80) with malignant lymphoma (22 patients with Hodgkin's disease [HD] and 47 patients with Non-Hodgkin's lymphoma [NHL]) who had not received treatment before 18F-FDG PET imaging. Metabolic remission according to PET results was observed after chemotherapy in 50 patients (72.5%), while progressive disease or relapse was diagnosed in 19 patients (27.5%). Clinical follow-up revealed relapse in 4/50 patients with prior metabolic remission. A significantly lower (P < 0.01) baseline SUV max level (median: 4.6 and range 1.5-12.9) was found in patients with subsequent metabolic and clinical response than in those with progressive or relapsing disease (median SUV max 10.4, range 2.0-17.9). Thirty-seven of thirty-nine patients with baseline SUV max < 7.4 achieved long-lasting remission after completion of chemotherapy (median follow-up: 28 months, range 4-112 months). Within this group with favorable outcome, there were no significant differences between SUV max values in HD and NHL. A heterogeneous outcome was noted in 25 patients with a SUV max ≥ 7.4 and ≤ 12.9 at diagnosis, with 16 patients experiencing disease progression or relapse and nine patients extended remission. The five patients with SUV max > 12.9 showed disease progression at follow-up. Semiquantitative measurement of glucose metabolism (SUV max) by 18F-FDG PET at diagnosis is a predictor of outcome of patients with malignant lymphoma. © 2010 Springer Science+Business Media, LLC.


PubMed | Institute of Nuclear Medicine with Center
Type: Journal Article | Journal: Wiener klinische Wochenschrift | Year: 2013

The present study was undertaken to estimate the selenium intake of thyroid patients and investigate the possible relation between thyroid abnormalities and the selenium intake.The selenium intake through foods and the nutritional habits of thyroid patients in general were analyzed. Total 212 subjects from thyroid outpatient clinic of two state hospitals were interviewed. Among 212 subjects, 21 had no thyroid abnormality and served as controls. A food frequency questionnaire (FFQ) was developed to define the individual selenium intakes. From five different food groups, a total of 15 selenium-rich foods were selected, which are obtainable in Austria. The clinical and nutritional data were analyzed.Animal products such as milk and meat (pork, beef and poultry) played the most important role for the selenium supply in the Austrian diet. The intake of selenium in 86% of the total study population was below the estimated average requirement (EAR). The selenium level was higher in euthyroid people compared with hypothyroid patients.The developed FFQ is a tool to estimate the selenium intake in individuals, as it could be shown in this study. A significant positive correlation between selenium intake and blood selenium level was noted. These results must be confirmed by further studies in larger patient population.


PubMed | Institute of Nuclear Medicine with Center
Type: Journal Article | Journal: Oncology | Year: 2011

Peptide receptor-targeted radionuclide therapy (PRRT) of somatostatin receptor (SR)-expressing neuroendocrine tumors (NETs) has become an established therapeutic option in patients with advanced NETs. The aim of this study was to compare the lesion detection rate of (99m)Tc-EDDA/HYNIC-TOC, a newly developed tracer for NET imaging, with (177)Lu-DOTATATE used for PRRT.8 patients (4 women, 4 men, age range 46-76 years) with histologically proven NETs, who showed high SR loads by (99m)Tc-EDDA/HYNIC-TOC scintigraphy, were treated with (177)Lu-DOTATATE. After treatment, all patients were subjected to whole-body scintigraphy with additional low-dose single-photon emission computed tomography (SPECT-CT) of the chest and abdomen.All patients demonstrated (177)Lu-DOTATATE accumulation in all lesions previously detected by (99m)Tc- EDDA/HYNIC-TOC scintigraphy. Three patients showed additional lesions in the liver and lungs.SPECT-CT after (177)Lu-DOTATATE therapy may be helpful in detecting additional lesions not seen using (99m)Tc-EDDA/HYNIC-TOC. This could reflect the broader affinity of (177)Lu-DOTATATE for SRs compared with (99m)Tc-EDDA/HYNIC-TOC.


PubMed | Institute of Nuclear Medicine with Center
Type: Journal Article | Journal: Medical oncology (Northwood, London, England) | Year: 2011

Metabolic imaging with F-18-fluorodeoxyglucose (18F-FDG) positron-emission tomography (PET) is widely used for staging and treatment evaluation of malignant lymphoma. To date, only a few studies have indicated that lower glucose metabolism measured by 18F-FDG PET before or early in the course of treatment of malignant lymphoma is associated with a favorable outcome. The aim of this study was to assess the prognostic capability of the 18F-FDG PET maximum standardized uptake value (SUVmax), a semiquantitative measurement of glucose metabolism, at the time of diagnosis of malignant lymphoma. We retrospectively analyzed data from 69 patients (median age: 61 and range 23-80) with malignant lymphoma (22 patients with Hodgkins disease [HD] and 47 patients with Non-Hodgkins lymphoma [NHL]) who had not received treatment before 18F-FDG PET imaging. Metabolic remission according to PET results was observed after chemotherapy in 50 patients (72.5%), while progressive disease or relapse was diagnosed in 19 patients (27.5%). Clinical follow-up revealed relapse in 4/50 patients with prior metabolic remission. A significantly lower (P<0.01) baseline SUVmax level (median: 4.6 and range 1.5-12.9) was found in patients with subsequent metabolic and clinical response than in those with progressive or relapsing disease (median SUVmax 10.4, range 2.0-17.9). Thirty-seven of thirty-nine patients with baseline SUVmax<7.4 achieved long-lasting remission after completion of chemotherapy (median follow-up: 28 months, range 4-112 months). Within this group with favorable outcome, there were no significant differences between SUVmax values in HD and NHL. A heterogeneous outcome was noted in 25 patients with a SUVmax7.4 and 12.9 at diagnosis, with 16 patients experiencing disease progression or relapse and nine patients extended remission. The five patients with SUVmax>12.9 showed disease progression at follow-up. Semiquantitative measurement of glucose metabolism (SUVmax) by 18F-FDG PET at diagnosis is a predictor of outcome of patients with malignant lymphoma.

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