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PURPOSE: Identifying gastroduodenal uptake of (99m)Tc-macroaggregated albumin (MAA), which is associated with an increased risk of ulcer disease, is a crucial part of the therapeutic management of patients undergoing radioembolization for liver tumours. Given this context, the use of MAA single photon emission computed tomography (SPECT)/CT may be essential, but the procedure has still not been thoroughly evaluated. The aim of this retrospective study was to determine the effectiveness of MAA SPECT/CT in identifying digestive extrahepatic uptake, while determining potential diagnostic pitfalls. METHODS: Overall, 139 MAA SPECT/CT scans were performed on 103 patients with different hepatic tumour types. Patients were followed up for at least 6 months according to standard requirements. RESULTS: Digestive, or digestive-like, uptake other than free pertechnetate was identified in 5.7% of cases using planar imaging and in 36.6% of cases using SPECT/CT. Uptake sites identified by SPECT/CT included the gastroduodenal region (3.6%), gall bladder (12.2%), portal vein thrombosis (6.5%), hepatic artery (6.5%), coil embolization site (2.1%) as well as falciform artery (5.0%). For 2.1% of explorations, a coregistration error between SPECT and CT imaging could have led to a false diagnosis by erroneously attributing an uptake site to the stomach or gall bladder, when the uptake actually occurred in the liver. CONCLUSION: SPECT/CT is more efficacious than planar imaging in identifying digestive extrahepatic uptake sites, with extrahepatic uptake observed in one third of scans using the former procedure. However, more than half of the uptake sites in our study were vascular in nature, without therapeutic implications. The risk of coregistration errors must also be kept in mind.
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Sistema Digestório/metabolismo , Embolização Terapêutica , Neoplasias Hepáticas/radioterapia , Imagem Multimodal , Tomografia por Emissão de Pósitrons , Planejamento da Radioterapia Assistida por Computador/métodos , Compostos de Sulfidrila/metabolismo , Agregado de Albumina Marcado com Tecnécio Tc 99m/metabolismo , Tomografia Computadorizada por Raios X , Idoso , Transporte Biológico , Embolização Terapêutica/efeitos adversos , Reações Falso-Positivas , Feminino , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/metabolismo , Masculino , Estudos Retrospectivos , Compostos de Sulfidrila/efeitos adversos , Agregado de Albumina Marcado com Tecnécio Tc 99m/efeitos adversos , Úlcera/etiologia , Úlcera/metabolismoRESUMO
Background: The American Thyroid Association (ATA), the European Association of Nuclear Medicine, the European Thyroid Association, and the Society of Nuclear Medicine and Molecular Imaging have established an intersocietal working group to address the current controversies and evolving concepts in thyroid cancer management and therapy. The working group annually identifies topics that may significantly impact clinical practice and publishes expert opinion articles reflecting intersocietal collaboration, consensus, and suggestions for further research to address these important management issues. Summary: In 2019, the intersocietal working group identified the following topics for review and interdisciplinary discussion: (i) perioperative risk stratification, (ii) the role of diagnostic radioactive iodine (RAI) imaging in initial staging, and (iii) indicators of response to RAI therapy. Conclusions: The intersocietal working group agreed that (i) initial patient management decisions should be guided by perioperative risk stratification that should include the eighth edition American Joint Committee on Cancer staging system to predict disease specific mortality, the modified 2009 ATA risk stratification system to estimate structural disease recurrence, with judicious incorporation of molecular theranostics to further refine management recommendations; (ii) diagnostic RAI scanning in ATA intermediate risk patients should be utilized selectively rather than being considered mandatory or not necessary for all patients in this category; and (iii) a consistent semiquantitative reporting system should be used for response evaluations after RAI therapy until a reproducible and clinically practical quantitative system is validated.
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Radioisótopos do Iodo , Medicina de Precisão , Neoplasias da Glândula Tireoide/diagnóstico , Neoplasias da Glândula Tireoide/terapia , Consenso , Humanos , Medição de RiscoRESUMO
OBJECTIVES: We report a first experience involving the use of (90)Y radiolabelled microspheres (TheraSphere) for the treatment of mainly primary hepatic tumours. MATERIALS AND METHODS: Treatment using TheraSphere microspheres was planned in 15 patients (13 with hepatocellular carcinoma, 2 with neuroendocrine tumour metastases). The treatment was preceded by a first angiography aimed at embolizing the vascularizing arterial branches of other structures outside the liver and evaluating the percentage of pulmonary shunt by scintiscanning after perfusion with (99m)Tc-MAA. The objective of the treatment carried out during a second angiography was to deliver a dose of 120+/-20 Gy (mean+/-SD) to the target hepatic volume. RESULTS: Technical difficulties were encountered in embolizing gastroduodenal or gastric branches in two patients and in one patient these led to cancellation of the treatment. A total of 14 patients were treated with an average activity of 3.18 GBq. In one patient, the injection was defective (stagnation of microspheres at the outlet of the catheter). SPECT/CT acquisitions provided important information in four patients (visualization of the gallbladder in three; visualization of the stomach in one, leading to a new coiling). The average exposure of the nuclear medicine physician carrying out the injections was 64+/-80 microSv at the fingers. A partial response was seen in six patients, stabilization in five and progression in three. One patient presented with a gastric ulcer and two showed an increase in their hepatocellular insufficiency. CONCLUSION: Although sometimes technically difficult, the use of TheraSphere microspheres is a worthwhile therapeutic approach because of the low level exposure of operators and the encouraging rate of response or stabilization. The use of SPECT/CT contributes greatly to helping therapeutic planning, especially in the learning curve or when the angiographic procedure is difficult.
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Embolização Terapêutica/métodos , Neoplasias Hepáticas/terapia , Microesferas , Radioisótopos de Ítrio/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/terapia , Feminino , Humanos , Injeções , Neoplasias Hepáticas/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Exposição Ocupacional , Médicos , Estudos Retrospectivos , Tomografia Computadorizada de Emissão de Fóton Único , Tomografia Computadorizada por Raios X , Radioisótopos de Ítrio/administração & dosagem , Radioisótopos de Ítrio/químicaRESUMO
AIM: 18F-Choline (FCH) uptake parameters are strong indicators of aggressive disease in prostate cancer. Functional parameters derived by magnetic resonance imaging (MRI) are also correlated to aggressive disease. The aim of this work was to evaluate the relationship between metabolic parameters derived by FCH PET/CT and functional parameters derived by MRI. MATERIALS AND METHODS: Fourteen patients with proven prostate cancer who underwent FCH PET/CT and multiparametric MRI were enrolled. FCH PET/CT consisted in a dual phase: early pelvic list-mode acquisition and late whole-body acquisition. FCH PET/CT and multiparametric MRI examinations were registered and tumoral volume-of-interest were drawn on the largest lesion visualized on the apparent diffusion coefficient (ADC) map and projected onto the different multiparametric MR images and FCH PET/CT images. Concerning the FCH uptake, kinetic parameters were extracted with the best model selected using the Akaike information criterion between the one- and two-tissue compartment models with an imaging-derived plasma input function. Other FCH uptake parameters (early SUVmean and late SUVmean) were extracted. Concerning functional parameters derived by MRI scan, cell density (ADC from diffusion weighting imaging) and vessel permeability (Ktrans and Ve using the Tofts pharmakinetic model from dynamic contrast-enhanced imaging) parameters were extracted. Spearman's correlation coefficients were calculated to compare parameters. RESULTS: The one-tissue compartment model for kinetic analysis of PET images was selected. Concerning correlation analysis between PET parameters, K1 was highly correlated with early SUVmean (r = 0.83, p < 0.001) and moderately correlated with late SUVmean (r = 0.66, p = 0.010) and early SUVmean was highly correlated with late SUVmean (r = 0.90, p < 0.001). No significant correlation was found between functional MRI parameters. Concerning correlation analysis between PET and functional MRI parameters, K1 (from FCH PET/CT imaging) was moderately correlated with Ktrans (from perfusion MR imaging) (r = 0.55, p = 0.041). CONCLUSIONS: No significant correlation was found between FCH PET/CT and multiparametric MRI metrics except FCH influx which is moderately linked to the vessel permeability in prostate cancer.
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Colina , Radioisótopos de Flúor , Imageamento por Ressonância Magnética , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Neoplasias da Próstata/diagnóstico por imagem , Idoso , Humanos , Processamento de Imagem Assistida por Computador , Cinética , Masculino , Pessoa de Meia-IdadeRESUMO
BACKGROUND: Publication of the 2015 American Thyroid Association (ATA) management guidelines for adult patients with thyroid nodules and differentiated thyroid cancer was met with disagreement by the extended nuclear medicine community with regard to some of the recommendations related to the diagnostic and therapeutic use of radioiodine (131I). Because of these concerns, the European Association of Nuclear Medicine and the Society of Nuclear Medicine and Molecular Imaging declined to endorse the ATA guidelines. As a result of these differences in opinion, patients and clinicians risk receiving conflicting advice with regard to several key thyroid cancer management issues. SUMMARY: To address some of the differences in opinion and controversies associated with the therapeutic uses of 131I in differentiated thyroid cancer constructively, the ATA, the European Association of Nuclear Medicine, the Society of Nuclear Medicine and Molecular Imaging, and the European Thyroid Association each sent senior leadership and subject-matter experts to a two-day interactive meeting. The goals of this first meeting were to (i) formalize the dialogue and activities between the four societies; (ii) discuss indications for 131I adjuvant treatment; (iii) define the optimal prescribed activity of 131I for adjuvant treatment; and (iv) clarify the definition and classification of 131I-refractory thyroid cancer. CONCLUSION: By fostering an open, productive, and evidence-based discussion, the Martinique meeting restored trust, confidence, and a sense of collegiality between individuals and organizations that are committed to optimal thyroid disease management. The result of this first meeting is a set of nine principles (The Martinique Principles) that (i) describe a commitment to proactive, purposeful, and inclusive interdisciplinary cooperation; (ii) define the goals of 131I therapy as remnant ablation, adjuvant treatment, or treatment of known disease; (iii) describe the importance of evaluating postoperative disease status and multiple other factors beyond clinicopathologic staging in 131I therapy decision making; (iv) recognize that the optimal administered activity of 131I adjuvant treatment cannot be definitely determined from the published literature; and (v) acknowledge that current definitions of 131I-refractory disease are suboptimal and do not represent definitive criteria to mandate whether 131I therapy should be recommended.
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Diferenciação Celular , Radioisótopos do Iodo/uso terapêutico , Radioterapia (Especialidade)/normas , Compostos Radiofarmacêuticos/uso terapêutico , Neoplasias da Glândula Tireoide/radioterapia , Consenso , Medicina Baseada em Evidências/normas , Humanos , Radioisótopos do Iodo/efeitos adversos , Compostos Radiofarmacêuticos/efeitos adversos , Neoplasias da Glândula Tireoide/patologiaRESUMO
OBJECTIVE: Vectorized internal radiation therapy using lipiodol-labelled with iodine-131 (131 I-lipiodol) is an effective treatment for inoperable hepatocellular carcinomas. However, few dosimetric data are available based on this approach. We have developed a dosimetric protocol based on scintiscan imaging and that is designed to calculate the tumoural absorbed dose during the treatment of hepatocarcinoma by 131 I-lipiodol. METHODS: This concept was developed on a gamma-camera coupled to a computed tomography scanner. It integrates corrections for attenuation phenomena, scattering and dead time. The tumoural absorbed dose calculation was carried out according to the Medical Internal Radiation Dose Committee formalism. This protocol was applied to a series of 41 patients in the framework of a retrospective study. RESULTS: The mean tumoural absorbed dose with the first treatment is 248 Gy (+/-176), as opposed to 152 Gy (+/-122) during the second. We highlighted a correlation between the tumoural absorbed dose, calculated in tomographic mode, and the morphological response to the first treatment (P=0.0071). Moreover, a tumoural absorbed dose of 280 Gy seems to be an effective absorbed dose threshold in our population. Above this absorbed dose, 84% of the patients are responders after the first treatment, whereas no responses are recorded below this threshold. CONCLUSION: These results are promising because, for the first time, they allow us to predict the effectiveness of a treatment by 131 I-lipiodol. They are required to be validated on a broader exploratory trial, including a dosimetric study of the critical organs, so an individualized dosimetry can be defined for each patient.
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Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/radioterapia , Radioisótopos do Iodo/farmacologia , Óleo Iodado/farmacologia , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/radioterapia , Radiometria/instrumentação , Idoso , Idoso de 80 Anos ou mais , Calibragem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Radiometria/métodos , Cintilografia , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodos , Resultado do TratamentoRESUMO
BACKGROUND: Suboptimal temporal sampling of time-activity curves (TAC) from dynamic 18F-fluoromethylcholine (FCH) PET images may introduce bias in quantification of FCH uptake in prostate cancer assessment. We sought to define an optimal temporal sampling protocol for dynamic FCH PET imaging. Seven different time samplings were tested: 5 × 60â³, 10 × 30â³, 15 × 15â³-1 × 75â³, 6 × 10â³-8 × 30â³, 12 × 5â³-8 × 30â³; 10 × 5â³-4 × 10â³-3 × 20â³-5 × 30â³, and 8 × 3â³-8 × 12â³-6 × 30â³. First, the irreversible and reversible one-tissue compartment model with blood volume parameter (VB) (respectively, 1T1K+VB and 1T2k+VB, with K1 = transfer coefficient from the arterial blood to the tissue compartment and k2 = transfer coefficient from the tissue compartment to the arterial blood) were compared for 37 lesions from 32 patients who underwent FCH PET imaging for initial or recurrence assessment of prostate cancer, and the model was selected using the Akaike information criterion. To determine the optimal time sampling, K1 values extracted from 1000 noisy-simulated TAC using Monte Carlo method from the seven different time samplings were compared to a target K1 value which is the average of the K1 values extracted from the 37 lesions using an imaging-derived input function for each patient. K1 values extracted with the optimal time sampling for each tumoral lesion were compared to K1 values extracted from each of the other time samplings for the 37 lesions. RESULTS: The 1T2k + VB model was selected. The target K1 value as the objective was 0.506 mL/ccm/min (range 0.216-1.246). Results showed a significant difference between K1 values from the simulated TAC with the seven different time samplings analyzed. The closest K1 value from the simulated TAC to the target K1 value was obtained by the 12 × 5â³-8 × 30â³ time sampling. Concerning the clinical validation, K1 values extracted from the optimal time sampling (12 × 5â³-8 × 30â³) were significantly different with K1 values extracted from the other time samplings, except for the comparison with K1 values extracted from the 10 × 5â³-4 × 10â³-3 × 20â³-5 × 30â³ time sampling. CONCLUSIONS: A two-phase framing of dynamic PET reconstruction with frame durations of 5 s (blood phase) and 30 s (tissue phase) could be used to sample the TAC for uptake quantification in prostate cancer assessment.
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AIM: The aim of the study was to compare the kinetic analysis of 18F-labeled choline (FCH) uptake with static analysis and clinicopathological parameters in patients with newly diagnosed prostate cancer (PC). MATERIALS AND METHODS: Sixty-one patients were included. PSA was performed few days before FCH PET/CT. Gleason scoring (GS) was collected from systematic sextant biopsies. FCH PET/CT consisted in a dual phase: early pelvic list-mode acquisition (from 0 to10 min post-injection) and late whole-body acquisition (60 min post-injection). PC volume of interest was drawn using an adaptative thresholding (40% of the maximal uptake) on the late acquisition and projected onto an early static frame of 10 min and each of the 20 reconstructed frames of 30 s. Kinetic analysis was performed using an imaging-derived plasma input function. Early kinetic parameter (K1 as influx) and static parameters (early SUVmean, late SUVmean, and retention index) were extracted and compared to clinicopathological parameters. RESULTS: K1 was significantly, but moderately correlated with early SUVmean (r = 0.57, p < 0.001) and late SUVmean (r = 0.43, p < 0.001). K1, early SUVmean, and late SUVmean were moderately correlated with PSA level (respectively, r = 0.36, p = 0.004; r = 0.67, p < 0.001; r = 0.51, p < 0.001). Concerning GS, K1 was higher for patients with GS ≥ 4 + 3 than for patients with GS < 4 + 3 (median value 0.409 vs 0.272 min- 1, p < 0.001). No significant difference was observed for static parameters. CONCLUSIONS: FCH influx index K1 seems to be related to GS and could be a non-invasive tool to gain further information concerning tumor aggressiveness.
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Colina/análogos & derivados , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/metabolismo , Idoso , Idoso de 80 Anos ou mais , Transporte Biológico , Colina/metabolismo , Humanos , Cinética , Masculino , Pessoa de Meia-IdadeRESUMO
BACKGROUND AND AIM: It has been shown that the use of a cocktail of isotopes of different ranges of action leads to an increase in the effectiveness of metabolic radiotherapy. The purpose of the present study was to compare with a control group the effectiveness of three different treatments in rats bearing hepatocellular carcinoma (HCC), using (1) a mixture of lipiodol labelled with both I and Re, (2) lipiodol labelled with I alone and (3) lipiodol labelled with Re alone. MATERIAL AND METHODS: Four groups were made up, each containing 14 rats with the N1-S1 tumour cell line. Group 1 received a mixture composed of 22 MBq of Re-SSS lipiodol and 7 MBq I-lipiodol. Group 2 received 14 MBq I-lipiodol. Group 3 received 44 MBq of Re-SSS lipiodol and group 4 acted as the control. The survival of the various groups was compared by a non-parametric test of log-rank, after a follow-up of 60, 180 and 273 days. RESULTS: Compared with the controls, the rats treated with a mixture of Re-SSS lipiodol and I-lipiodol show an increase in survival, but only from day 60 onwards (P=0.05 at day 60 and 0.13 at days 180 and 273). For the rats treated with I-lipiodol, there was a highly significant increase in survival compared with the controls at day 60, day 180 and day 273 (P=0.03, 0.04 and 0.04, respectively). There is no significant increase in survival for the rats treated with Re-SSS lipiodol, irrespective of the follow-up duration (P=0.53 at day 60, 0.48 at day 180, and 0.59 at day 273). CONCLUSIONS: In this study, I-lipiodol is the most effective treatment in HCC-bearing rats, because this is the only method that leads to a prolonged improvement of survival. These results cannot necessarily be extrapolated to humans because of the relatively small size and unifocal nature of the lesions in this study. It appears necessary to carry out a study in humans with larger tumours in order to compare these three treatments, particularly with a view to replacing I-labelled lipiodol by Re-labelled lipiodol. However, this study clearly demonstrated that, for small tumours, as in an adjuvant setting for example, I-labelled lipiodol should be a better option than Re-labelled lipiodol.
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Carcinoma Hepatocelular/radioterapia , Radioisótopos do Iodo/administração & dosagem , Óleo Iodado/administração & dosagem , Neoplasias Hepáticas/radioterapia , Compostos Organometálicos/administração & dosagem , Taxa de Sobrevida , Animais , Combinação de Medicamentos , Feminino , Prognóstico , Compostos Radiofarmacêuticos/administração & dosagem , Ratos , Ratos Sprague-Dawley , Análise de Sobrevida , Resultado do TratamentoRESUMO
UNLABELLED: The aim of this study was to evaluate the diagnostic value of a new somatostatin analog, 99mTc-P829, compared with that of 111In-pentetreotide. METHODS: Forty-three patients (32 men, 11 women; age range, 24-78 y; mean age, 56 y) with biologically or histologically proven neuroendocrine tumors were prospectively included: 11 patients with Zollinger-Ellison syndrome, 16 patients with carcinoid tumors, and 16 patients with other types of functioning (n = 6) or nonfunctioning (n = 10) endocrine tumors. 111In-Pentetreotide planar images (head, chest, abdomen, and pelvis) were obtained 4 and 24 h after injection of 10 microg somatostatin analog labeled with 148 +/- 17 MBq 111In, and SPECT was performed 24 h after injection. Similar (99m)Tc-P829 planar images were obtained at 1, 4-6, and 24 h after injection of 50 microg peptide labeled with 991.6 +/- 187.59 MBq 99mTc. Abdominal SPECT was performed 4-6 h after injection. RESULTS: 111In-Pentetreotide detected 203 tumoral sites in 39 (91%) of 43 patients, whereas 99mTc-P829 detected 77 sites in 28 (65%) of 43 patients (P < 0.005). In the liver, 129 sites (in 24 patients) were detected by 111In-pentetreotide scintigraphy and 34 sites (in 10 patients) were detected by 99mTc-P829 scintigraphy. CONCLUSION: In patients with endocrine tumors, the detection rate of 99mTc-P829 scintigraphy was lower than that of 111In-pentetreotide scintigraphy, which appeared to be more sensitive, especially for liver metastases.
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Radioisótopos de Índio , Tumores Neuroendócrinos/diagnóstico por imagem , Compostos de Organotecnécio , Peptídeos Cíclicos , Somatostatina , Tumor Carcinoide/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Compostos Radiofarmacêuticos , Somatostatina/análogos & derivados , Tomografia Computadorizada de Emissão de Fóton Único , Síndrome de Zollinger-Ellison/diagnóstico por imagemRESUMO
BACKGROUND: Although intra-arterial radiation therapy with 131I-lipiodol is a useful therapeutic approach to the treatment of hepatocellular carcinoma, various disadvantages limit its use. AIM: To describe the development of a method for the labelling of lipiodol with 188Re-SSS (188Re (S2CPh)(S3CPh)2 complex) and to investigate its biodistribution after injection into the hepatic artery of rats with hepatoma. METHODS: 188Re-SSS lipiodol was obtained after dissolving a chelating agent, previously labelled with 188Re, in cold lipiodol. The radiochemical purity (RCP) of labelling was checked immediately. The 188Re-SSS lipiodol was injected into the hepatic artery of nine rats with a Novikoff hepatoma. They were sacrificed 1, 24 and 48 h after injection, and used for ex vivo counting. RESULTS: Labelling of 188Re-SSS lipiodol was achieved with a yield of 97.3+/-2.1%. The immediate RCP was 94.1+/-1.7%. Ex vivo counting confirmed a predominantly hepatic uptake, with a good tumoral retention of 188Re-SSS lipiodol, a weak pulmonary uptake and a very faint digestive uptake. The 'tumour/non-tumoral liver' ratio was high at 1, 24 and 48 h after injection (2.9+/-1.5, 4.1+/-/4.1 and 4.1+/-0.7, respectively). CONCLUSIONS: Using the method described here, 188Re-SSS lipiodol can be obtained with a very high yield and a satisfactory RCP. The biodistribution in rats with hepatoma indicates a good tumoral retention of 188Re-SSS lipiodol associated with a predominant hepatic uptake, a weak pulmonary uptake and a very faint digestive uptake. This product should be considered for intra-arterial radiation therapy in human hepatoma.
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Carcinoma Hepatocelular/metabolismo , Óleo Iodado/administração & dosagem , Óleo Iodado/farmacocinética , Marcação por Isótopo/métodos , Neoplasias Hepáticas/metabolismo , Compostos Organometálicos/administração & dosagem , Compostos Organometálicos/farmacocinética , Animais , Combinação de Medicamentos , Avaliação Pré-Clínica de Medicamentos , Feminino , Injeções Intra-Arteriais , Taxa de Depuração Metabólica , Especificidade de Órgãos , Compostos Radiofarmacêuticos/administração & dosagem , Compostos Radiofarmacêuticos/síntese química , Compostos Radiofarmacêuticos/farmacocinética , Ratos , Ratos Sprague-Dawley , Distribuição Tecidual , Contagem Corporal TotalRESUMO
BACKGROUND: We develop a method for the radiolabelling of Lipiodol with Tc, using a lipophilic complex, [99mTc-(S2CPh)(S3Ph)2], dissolved in Lipiodol (99mTc-SSS Lipiodol). RESULTS: The labelling yield is high (96 +/- 0.8%), and the radiochemical purity satisfactory (92 +/- 2.6%). This labelling is reproducible and stable for up to 24 h in vitro. Studies carried out after injection into the hepatic artery of the healthy pig show that the biodistribution of 99mTc-SSS Lipiodol is comparable with that observed for 188Re Lipiodol. MATERIALS AND METHODS: The 99mTc-SSS lipiodol was obtained after dissolving a chelating agent, previously labelled with 99mTc, in cold lipiodol. The radiochemical purity (RCP) of the labelling was checked immediately and at 24 h. The 99mTc-SSS lipiodol was injected into the hepatic artery of four healthy pigs for an ex-vivo biodistribution study. An autoradiographic study was performed in two cases. CONCLUSIONS: Apart from the specific interest of a Lipiodol-bearing technetiated agent for carrying out dosimetric studies, the labelling of Lipiodol with 99mTc is a preliminary step towards the use of radiolabelling with the 188Re analogue.
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Artéria Hepática/metabolismo , Óleo Iodado/química , Óleo Iodado/farmacocinética , Marcação por Isótopo/métodos , Tecnécio/química , Tecnécio/farmacocinética , Animais , Estudos de Viabilidade , Artéria Hepática/efeitos dos fármacos , Inativação Metabólica , Injeções Intra-Arteriais , Especificidade de Órgãos , Compostos Radiofarmacêuticos/síntese química , Compostos Radiofarmacêuticos/farmacocinética , Suínos , Distribuição TecidualRESUMO
CONTEXT: The "Standards, Options and Recommendations" (SOR) project, started in 1993, is a collaboration between the Federation of French cancer centers (FNCLCC), the 20 French cancer centers, scientific societies, and specialists from French public universities, general hospitals and private clinics. The main objective is the development of clinical practice guidelines to improve the quality of health care and the outcome of cancer patients. The methodology is based on a literature review and critical appraisal by a multidisciplinary group of experts, with feedback from specialists in cancer care delivery. OBJECTIVES: To develop clinical practice guidelines for the use of positron emission tomography with [18F]-FDG in oncology according to the definitions of the Standards, Options and Recommendations project. METHODS: More than 600 articles were identified by searching Medline, web sites, and using the personal reference lists of members of the expert groups. Once the guidelines were defined, the document was submitted for review to independent reviewers (n = 82). RESULTS: The different steps in patient care are studied in this report: diagnosis of the primary disease, initial and secondary assessment of metastatic extension, evaluation of treatment response and examination for recurrence. The guidelines were developed for each cancer sites: bronchopulmonary and pleural cancers, melanomas, gynaecological cancers, gastrointestinal cancers, head and neck cancers, urological cancers, lymphomas, soft-tissue and bone sarcomas, cancers of the thyroid and carcinomas of unknown primary site. The recommendations were made on the basis of data published up to February 2002. Systematic monitoring of the new scientific data on FDG-PET has been set up by the working group of the FNCLCC, which will ensure dissemination of the updating on its web site: www.fnclcc.fr/sor.htm.
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Fluordesoxiglucose F18 , Neoplasias/diagnóstico por imagem , Guias de Prática Clínica como Assunto , Compostos Radiofarmacêuticos , Tomografia Computadorizada de Emissão/normas , França , Humanos , Sociedades MédicasAssuntos
Fluordesoxiglucose F18 , Neoplasias Renais/diagnóstico por imagem , Tomografia por Emissão de Pósitrons , Neoplasias da Próstata/diagnóstico por imagem , Compostos Radiofarmacêuticos , Neoplasias Testiculares/diagnóstico por imagem , Neoplasias da Bexiga Urinária/diagnóstico por imagem , França , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Ciência de Laboratório MédicoRESUMO
The goal of this study was to assess the use of quantitative single-photon emission computed tomography/computed tomography (SPECT/CT) analysis for vascularized volume measurements in the use of the yttrium-90-radiolabeled microspheres (TheraSphere). A phantom study was conducted for the validation of SPECT/CT volume measurement. SPECT/CT quantitative analysis was used for the measurement of the volume of distribution of the albumin macroaggregates (MAA; i.e., the vascularized volume) in the liver and the tumor, and the total activity contained in the liver and the tumor in four consecutive patients presenting with a complex liver vascularization referred for a treatment with TheraSphere. SPECT/CT volume measurement proved to be accurate (mean error <7%) and reproducible (interobserver concordance 0.99). For eight treatments, in cases of complex hepatic vascularization, the hepatic volumes based on angiography and CT led to a relative overestimation or underestimation of the vascularized hepatic volume by 43.2 ± 32.7% (5-87%) compared with SPECT/CT analyses. The vascularized liver volume taken into account calculated from SPECT/CT data, instead of angiography and CT data, results in modifying the activity injected for three treatments of eight. Moreover, quantitative analysis of SPECT/CT allows us to calculate the absorbed dose in the tumor and in the healthy liver, leading to doubling of the injected activity for one treatment of eight. MAA SPECT/CT is accurate for volume measurements. It provides a valuable contribution to the therapeutic planning of patients presenting with complex hepatic vascularization, in particular for calculating the vascularized liver volume, the activity to be injected and the absorbed doses. Studies should be conducted to assess the role of quantitative MAA/SPECT CT in therapeutic planning.