Preparation for radioiodine therapy: How to increase therapeutic efficacy and accelerate unbound radioiodine excretion

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Comparison of thyroglobulin concentrations measured by two immunoradiometric assay

© 2020, University of Kragujevac, Faculty of Science. All rights reserved. Circulating thyroglobulin measurements is a highly specific test in the management of patients affected by differentiated thyroid cancer after total thyroidectomy, followed by radioiodine ablation. The aim of our study was to com-pare two thyroglobulinimmunoradiometric assays (INEP, Serbia and Cisbio Bioassays, France). Study included 42 patients of both genders with DTC. The subjects were on suppres¬sive doses of levothyroxine and followed up. Results showed concordance between the two assay methods for determining serum thyroglobulin for 39 (92.85%) pa-tients. Statistical analysis showed that there was a direct correlation between two IRMA tests, with a positive correlation coefficient r=0.613 (p 0.05). We concluded that there is good agreement between the two thyroglobulin assays compared in this study

Redox Parameters in Blood of Thyroid Cancer Patients After the Radioiodine Ablation

The radioactive iodine (I-131) ablation is a well-accepted treatment modality for differentiated thyroid cancer patients. Unfortunately, the radiation induces the oxidative stress and damages cells and tissues, simultaneously activating the mechanisms of antioxidative defense. Since the mechanisms of those processes are not completely known, we wanted to examine the changes in the most important reactive oxygen species and antioxidative components, as well as their correlation and significance for lipid peroxidation. Our results showed that the level of thiobarbituric acid reactive substances was increased during the first 30 days after the radiotherapy. Among antioxidant components, superoxide dismutase was increased in the 3rd and 30th day; catalase in 7th and reduced glutathione in 3rd and 7th day after the radiotherapy. As regards the prooxidants, the reduction of hydrogen peroxide (H2O2) was recorded in 7th and 30th day, and superoxide anion radical (O-2(center dot-)) was unchanged after the exposure to I-131. These results indicate that differentiated thyroid cancer patients are under constant oxidative stress despite the observed increase in antioxidative and reduction in prooxidative parameters. The understanding of these early processes is important since their progress determines the latter effects of I-131 therapy

Diagnostic nuclear medicine in pediatric oncology-what we should know before scanning?

Cancer is second only to trauma as a cause of death in children, accounting for approximately 10% of all childhood deaths. The application of radioisotopes in the treatment of malignant diseases in children consists of detecting and estimating the degree of tumour spread by application of tumour-specific and non-specific radiopharmaceuticals, as well as the treatment of some malignant diseases. Paramount to any successful nuclear medicine examination is the establishment of acquisition protocols that allow high quality images to be obtained while ALARA principles are followed. Pediatric-specific issues should be anticipated and addressed in the planning of the studies to maximize the utility of the technique in this challenging group of patients, so the goal of this article is to summarize general prerequisites for the application of nuclear medicine diagnostic procedures in pediatric oncology patients. © 2012, Oncology Institute of Vojvodina, Sremska Kamenica

Diagnostic nuclear medicine in pediatric oncology-what we should know before scanning?

Cancer is second only to trauma as a cause of death in children, accounting for approximately 10% of all childhood deaths. The application of radioisotopes in the treatment of malignant diseases in children consists of detecting and estimating the degree of tumour spread by application of tumour-specific and non-specific radiopharmaceuticals, as well as the treatment of some malignant diseases. Paramount to any successful nuclear medicine examination is the establishment of acquisition protocols that allow high quality images to be obtained while ALARA principles are followed. Pediatric-specific issues should be anticipated and addressed in the planning of the studies to maximize the utility of the technique in this challenging group of patients, so the goal of this article is to summarize general prerequisites for the application of nuclear medicine diagnostic procedures in pediatric oncology patients.</jats:p

Composition of essential oils from three classes of juniper fruit from Serbia

Juniperus communis L. (Cupressaceae) is widely distributed in the forest region of Serbia. This refers especially to degraded and devastated forests and abandoned farmlands. In addition to ecological significance as a pioneer species in forest regeneration, it is also of high economic interest. Its fruit (Juniperi fructi) produces a valuable essential oil (Juniperi aetherolium). Samples of J. communis fruits were collected from different places in Serbia and the content of essential oil was determined. Mature fruits were analyzed, with the content of unripe fruits up to 5%. The content of essential oils ranged between 2.30 and 2.66%. © 2011 Academic Journals

Online remote monitoring of patients with differentiated thyroid carcinomas and neuroendocrine tumors treated with high doses of radionuclides

Background: Telemedicine could be very useful for patients in remote areas experiencing adverse drug reactions or being in need of sophisticated diagnostic or therapeutic procedures. The aim of this article is to show the experience of our Department of Nuclear Medicine (DNM) in telemonitoring patients with differentiated thyroid carcinomas and neuroendocrine tumors. Subjects and Methods: The DNM at the Clinical Center Kragujevac, Serbia, uses continuous remote monitoring of patients' vital functions, including heart rate, electrocardiogram, respiration rate, blood pressure, and oxygen saturation, as well as video surveillance of the physical isolation area for patients with neuroendocrine tumors (NETs) and some patients with differentiated thyroid carcinomas (DTCs), during administration of radionuclide therapy and for the days following treatment. Results: The DNM used a telemonitoring system for 156 patients with either DTC or NET who received radionuclide therapy during the last 3 years. There were 32 interventions on patients in the physical isolation area based on changes of the patients' vital functions detected by the telemonitoring system. Twenty-five patients (78%) experienced symptoms, whereas the other seven patients (22%) were symptomless. A responsible physician intervened with treatment of tachycardia (18 cases), hypertension (10 cases), hypotension (2 cases), ventricular extrasystoles (1 case), and ST-segment depression (1 case). After administration of the treatment the health status of the patients was normalized. Conclusion: From our experience gained over the past 3 years, this model of organization and supervision with a telemonitoring system of patients receiving radionuclide therapy ensures a high level of safety for the patient, with significant reduction of staff costs. © Copyright 2012, Mary Ann Liebert, Inc

Somatostatin receptor molecular imaging in a misdiagnosed gastrinoma case

AbstractGastrin-secreting tumors, hypergastrinemia and severe ulcer disease form the trademarks of Zollinger-Ellison syndrome (ZES). We report a case of gastrinoma, in a patient who was misdiagnosed for almost five years. The case emphsizes the the special role of functional imaging in the personalized approach to the patient with suggestive symptomatology for NETs. Taking into account that in 80 to 100% of cases of gastroenteropancreatic (GEP) NETs are expressing somatostatin receptors, the functional imaging with radiolabeled somatostatin analogues can be used in order to improve its diagnosis, respectively the treatment of GEP NETs. In the approach to the patient with tremendous digestive symptomatology, physicians from different specialties should evaluate NETs specific markers and then insist on structural-functional complementarity, avoiding the waste of time and high cost of repeated structural investigations. The conclusion of our study is that functional imaging is mandatory in the diagnostic algorithm of gastrinoma.</jats:p

A five-compartment biokinetic model for ⁹⁰Y-DOTATOC therapy

© 2018 American Association of Physicists in Medicine Purpose: Neuroendocrine tumors (NETs) are now routinely treated by radiopeptide targeted therapy using somatostatin receptor-binding peptides such as 90Y- and 177Lu-DOTATOC. The objective of this work was to develop a biokinetics model of 90Y labelled DOTATOC, which is applied in the therapy of NETs to estimate doses in kidney and tumor. Methods: A multi-compartment model described by two sets of differential equations, one set for the actual 30-min infusion and the other set for the post-infusion period was developed and activities were measured by liquid scintillation counting in blood (compartment 1) and the urine (compartment 3). The inter-compartment transfer coefficients, λij, were varied to yield the best fit of the calculated to the measured time-activity data and the 90Y-DOTATOC time-activity data in the five-compartments comprising the human body were thus determined. The resulting time-activity curves were integrated over the interval from 0 to 72 h post administration to obtain the number of radioactive decays in each compartment and, in case of the kidneys and tumor, then multiplied by the self-dose 90Y beta particle absorbed fraction, determined by Monte Carlo (MC) simulation, the kidney and tumor absorbed doses. Results: Transfer coefficients λij, were determined for five-compartments for all patients. Time- activity curves of 90Y-DOTATOC in 14 patients were determined, and two typical ones are shown graphically. Absorbed doses in the tumor and kidneys, obtained by the developed method, were determined. The mean absorbed dose in a kidney per unit of administered activity is 1.43 mGy/MBq (range 0.73–2.42 mGy/MBq). The tumor dose was determined as 30.94 mGy/MBq (range 20.05–42.31 mGy/MBq). Conclusion: Analytical solution of a biokinetic model for 90Y-DOTATOC therapy enabled determination of the transfer coefficients and derivation of time-activity curves and kidney and tumor absorbed doses for 14 treated patients. The model can be applied to other radionuclides where elimination is predominantly through urine, which is often the case in radiopharmaceuticals