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1.
Crit Rev Oncol Hematol ; 138: 29-37, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31092382

RESUMO

BACKGROUND: Androgen Deprivation Therapy (ADT) is the primary treatment for patients suffering from relapsing or advanced prostate cancer (PC). Hormone therapy generally guarantees adequate clinical control of the disease for some years, even in those patients affected by widespread skeletal and soft tissue metastases. Despite ADT, however, most patients treated with hormones eventually progress to castration-resistant prostate cancer (CRPC), for which there are no effective treatments. This clinical reality is an open challenge to the oncologist because of those neoplasms which elaborate neuroendocrine differentiation (NED). METHODS: An online search of current and past literature on NED in CRPC was performed. Relevant articles dealing with the biological and pathological basis of NED, with nuclear medicine imaging in CRPC and somatostatin treatment in NED were analyzed. EVIDENCE FROM THE LITERATURE: NED may arise in prostate cancer patients in the late stages of ADT. The onset of NED offers prognostic insight because it reflects a dramatic increase in the aggressive nature of the neoplasm. Several genetic, molecular, cytological and immunohistochemical markers are associated with this transformation. Among these, overexpression of somatostatin receptors, seen through Nuclear Medicine testing, is one of the most studied. CONCLUSIONS: Preliminary studies show that the overexpression of somatostatin receptors related to NED in CRPC may easily be studied in vivo with PET/CT. This finding offers a potentially useful objective for targeted therapy in CRPC. If the overexpression of SSTRs is shown to afflict a significant segment of patients with CRPC, this will open further study of possible therapeutic options based on this marker.


Assuntos
Biomarcadores Tumorais/análise , Carcinoma Neuroendócrino/diagnóstico por imagem , Carcinoma Neuroendócrino/patologia , Neoplasias de Próstata Resistentes à Castração/diagnóstico por imagem , Neoplasias de Próstata Resistentes à Castração/patologia , Humanos , Masculino , Medicina Nuclear/métodos , Tomografia Computadorizada com Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos , Receptores de Somatostatina/análise
3.
Rev. esp. med. nucl. imagen mol. (Ed. impr.) ; 38(2): 123-135, mar.-abr. 2019. ilus, tab
Artigo em Espanhol | IBECS | ID: ibc-182400

RESUMO

El hiperparatiroidismo primario es una de las enfermedades endocrinas más frecuentes. Su diagnóstico es bioquímico. Las pruebas de imagen no tienen utilidad para el diagnóstico de esta afección, únicamente son pruebas localizadoras prequirúrgicas. En esta formación continuada analizaremos las diferentes modalidades de imagen empleadas en esta indicación, centrándonos en la Medicina Nuclear. La técnica de imagen más empleada en este contexto es la gammagrafía de paratiroides, en la actualidad la técnica de doble fase con 99mTc-MIBI y la de doble trazador 99mTc-MIBI/99mTc-pertecnetato, asociada en el primer caso a una SPECT o SPECT/TC, en tiempo precoz o tardío. La PET/TC con diferentes trazadores está demostrando buenos resultados, aplicada fundamentalmente en los casos de fallo de localización prequirúrgica de la gammagrafía. Exponemos, asimismo, los resultados de las técnicas de imagen morfológicas, y la utilidad de la combinación de técnicas


Primary hyperparathyroidism is one of the most frequent endocrine disorders. Its diagnosis is biochemical. Imaging techniques are not useful for the diagnosis of this pathology; they are just tools for pre-surgical localization. In this continuing education, we will analyze the different imaging modalities used in this indication, focusing on Nuclear Medicine. The most commonly used imaging technique in this context is the parathyroid scintigraphy, nowadays double phase protocol with 99mTc-MIBI and the double tracer with 99mTc-MIBI/99mTc-pertechnetate, associated in the first case to SPECT or SPECT/CT, in an early or late phase. The PET/CT with different tracers is showing good results, especially applied to cases of failure in the pre-surgical scintigraphic localization. We expose the results of the morphological imaging techniques as well as the usefulness of combining techniques


Assuntos
Humanos , Hiperparatireoidismo Primário/diagnóstico por imagem , Cintilografia/métodos , Tomografia Computadorizada com Tomografia por Emissão de Pósitrons/métodos , Cuidados Pré-Operatórios/métodos , Medicina Nuclear/métodos , Glândulas Paratireoides/diagnóstico por imagem , Compostos Radiofarmacêuticos/uso terapêutico
4.
Hell J Nucl Med ; 22(1): 2-3, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30843001

RESUMO

Sickle cell disease (SCD) is the best known haemoglobinopathy, caused by a mutation substituting valina for glutamic acid at position 6 of the beta-globin chain of adult hemoglobin A, resulting in hemoglobin S (HbS). The homozygous HbS disease (HbSS), an autosomal recessive disorder, is the most common form and the Mediterranean area, along with sub-Saharian African and India, have the highest prevalence (1%-15%). In particular, Sicily with a prevalence of 2%-5%, is among the most interested regions. However, migratory flows have led to a wider diffusion of the disease no longer confined to endemic areas. In Europe, the yearly estimate of affected births are 1,300 but more than 90% of children with SCD survive into adulthood thanks to screening programs and early available care; however, their lifespan remains shortened by two or three decades compared to general population. In Greece, the number of affected births surpassing 100,000 yearly and the total number of newborns carrying two deleterious genes, if no prevention measures are taken, is estimated to be about 120-130/year. Diagnosis of SCD is based on analysis of haemoglobin through protein electrophoresis or chromatography, that are cheap and widely available techniques, even if haemoglobin mass spectrometry and DNA analysis are techniques with high-throughput testing. Prenatal diagnosis is used in many European countries, so the number of affected newborns has significantly decreased during the last 3 years. Over the course of SCD, sickling process may cause acute and chronic abdominal pain due to vaso-occlusive crisis, bone pain often in long bones due to bone marrow infarction, chronic hemolytic anemia, splenic sequestration with rapid enlargement of the spleen, delayed sexual maturation and cholelithiasis, with important inter-indivuidual variability. Sickle hepatopathy reflects liver sickling process within hepatic sinusoids and includes gallstone disease, hepatic sequestration, hepatic sideroris, acute sickle cell hepatic crises (ASHC) and sickle cell intrahepatic cholestasis (SCIC). Clinically, it appears with fever, right upper quadrant pain, jaundice and increased serum liver function tests. These patients are repeatedly esposed to trasfused red cells that contributes to iron overload and may contribute to hepatic haemosiderosis. Increased bone turnover and resorption by osteoclasts and by marrow expansion due to activation of hematopoiesis. The hematopoietic system may expand physiologically. Computed tomography (CT) is an easily reproducible imaging method that allows the morphologic whole-body evaluation although with a high dose of radiation exposure and possible side effects from intravenous contrast media. Magnetic resonance cholangiopancreatography (MRCP) is a noninvasive technique without radiation chosen to image cholangiopathy and may be followed by the execution of endoscopic retrograde cholangiopancreatography (ERCP) in case of gallstone disease. Otherwise it can be helpful in identifying extramedullary hematopoiesis sites. Dual-energy X-rays absorptiometry (DEXA) is performed to evaluate deficit of bone mineral density (BMD), in which reduction of osteoblastic activity, high risk for necrosis may induce to fragility fractures. We recently had the experience of a typical case of a 56 years old Albanian woman with SCD, with jaundice after a long history of recurrent vaso-occlusive crisis. She was submitted to splenectomy and cholecystectomy 5 years before and since then she was treated with hydroxyurea. Hemocromatosis was excluded by genetic analysis. Hepatic biopsy (Pearl's stain) showed sinusoidal dilatation and diffuse iron accumulation in hepatocytes and Kupffer cells. Endo-hepatic jaundice was observed in MRCP images. It was interesting that DEXA examination was within normal range in both right proximal femur. This may probably be due to the presence of sclerotic lesions in the vertebrae, as was seen in the CT images. Technetium-99m-methylen bisphosphonate (99mTc-MDP) skeletal scintigraphy is a higly sensitive whole-body diagnostic nuclear medicine technique able to evaluate early bone metabolic changes. Multimodality SPET/CT allows to correlate scintigraphic findings with anatomical images with higher sensitivity and specificity. The higher uptake of 99mTc-MDP in SCD patients is due to the activation of hematopoetic system and relies on the osteoblastic response to bone resorption as in our patient. The 99mTc-MDP scan may be better than fluorine-18-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) to show sclerotic lesions. Technetium-99m nanocolloids bone marrow scintigraphy (BMS) provides information about the assessment of the reticulum-endothelial system (RES), the whole-body distribution of functional red bone marrow and the presence and the extent of extramedullary hematopoiesis, especially in liver, spleen and bone marrow. Fluorine-18-FDG PET/CT completes the whole-body assessment with an integrated multimodal approach with high spatial resolution that evaluates the metabolic activity and the standardized uptake value (SUV) in SCD patients. Modern genetic diagnosis and gene treatment give promise for having fewer cases of SCD in the future.


Assuntos
Anemia Falciforme/diagnóstico por imagem , Medicina Nuclear/métodos , Humanos
5.
Clin Nucl Med ; 44(5): 399-400, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30829868

RESUMO

A nuclear medicine shunt-o-gram is used to evaluate ventriculoperitoneal shunt patency and dispersion of radiotracer into the peritoneal cavity. A 73-year-old man presented with worsening memory, gait disturbance, and urinary incontinence. Shunt-o-gram revealed antegrade flow through the tubing and spillage into the peritoneal cavity without dispersion. CT confirmed a CSF-oma. Symptoms resolved after CSF-oma resection. Normal passage of radiotracer through the shunt without normal dispersion into the peritoneal cavity along with CT imaging correctly identified a CSF-oma. This is an unexpected complication of a shunt. Correct diagnosis on imaging likely saved this patient from unnecessary complete shunt revision.


Assuntos
Hidrocefalia/diagnóstico por imagem , Tomografia por Emissão de Pósitrons , Complicações Pós-Operatórias/diagnóstico por imagem , Derivação Ventriculoperitoneal/efeitos adversos , Idoso , Falha de Equipamento , Humanos , Hidrocefalia/cirurgia , Masculino , Medicina Nuclear/métodos , Complicações Pós-Operatórias/cirurgia
6.
Molecules ; 24(2)2019 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-30669256

RESUMO

The reliable and efficient production of radioisotopes for diagnosis and therapy is becoming an increasingly important capability, due to their demonstrated utility in Nuclear Medicine applications. Starting from the first processes involving the separation of 99mTc from irradiated materials, several methods and concepts have been developed to selectively extract the radioisotopes of interest. Even though the initial methods were based on liquid-liquid extraction (LLE) approaches, the perceived difficulty in automating such processes has slowly moved the focus towards resin separation methods, whose basic chemical principles are often similar to the LLE ones in terms of chelators and phases. However, the emerging field of flow chemistry allows LLE to be easily automated and operated in a continuous manner, resulting in an even improved efficiency and reliability. In this contribution, we will outline the fundamentals of LLE processes and their translation into flow-based apparatuses; in addition, we will provide examples of radioisotope separations that have been achieved using LLE methods. This article is intended to offer insights about the future potential of LLE to purify medically relevant radioisotopes.


Assuntos
Extração Líquido-Líquido , Radioisótopos/isolamento & purificação , Extração Líquido-Líquido/instrumentação , Extração Líquido-Líquido/métodos , Medicina Nuclear/instrumentação , Medicina Nuclear/métodos
8.
Eur J Nucl Med Mol Imaging ; 46(1): 217-223, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30267115

RESUMO

The aim of the review is to highlight articles published in 2017 in the Annals of Nuclear Medicine, an official peer-reviewed journal of the Japanese Society of Nuclear Medicine. Among all published manuscripts during the past year, we conducted a subjective selection of the most relevant topics. Fourteen fascinating articles are included in this review, ranging in topic from preclinical to clinical arenas.


Assuntos
Medicina Nuclear/métodos , Publicações Periódicas como Assunto , Cintilografia/métodos , Humanos , Japão , Sociedades Médicas , Nanomedicina Teranóstica/métodos
9.
Molecules ; 24(1)2018 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-30577598

RESUMO

The widespread availability of novel radioactive isotopes showing nuclear characteristics suitable for diagnostic and therapeutic applications in nuclear medicine (NM) has experienced a great development in the last years, particularly as a result of key advancements of cyclotron-based radioisotope production technologies. At Legnaro National Laboratories of the National Institute of Nuclear Physics (LNL-INFN), Italy, a 70-MeV high current cyclotron has been recently installed. This cyclotron will be dedicated not only to pursuing fundamental nuclear physics studies, but also to research related to other scientific fields with an emphasis on medical applications. LARAMED project was established a few years ago at LNL-INFN as a new research line aimed at exploiting the scientific power of nuclear physics for developing innovative applications to medicine. The goal of this program is to elect LNL as a worldwide recognized hub for the development of production methods of novel medical radionuclides, still unavailable for the scientific and clinical community. Although the research facility is yet to become fully operative, the LARAMED team has already started working on the cyclotron production of conventional medical radionuclides, such as Tc-99m, and on emerging radionuclides of high potential medical interest, such as Cu-67, Sc-47, and Mn-52.


Assuntos
Laboratórios , Medicina Nuclear , Radioisótopos , Compostos Radiofarmacêuticos , Ciclotrons , Instalações de Saúde , Humanos , Medicina Nuclear/métodos , Pesquisa
12.
ABC., imagem cardiovasc ; 31(4)Out.- Dez. 2018. ilus
Artigo em Português | LILACS | ID: biblio-963978
13.
Gac Med Mex ; 154(4): 509-519, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30250318

RESUMO

Los pacientes afectados por el cáncer diferenciado de tiroides habitualmente presentan un curso clínico favorable, ya que la piedra angular del tratamiento es la cirugía; a pesar de esto, algunos pueden desarrollar un ominoso desenlace, debido a las características clinico-patológicas de esta enfermedad. El tratamiento óptimo aún es controvertido, en especial respecto a la extensión de la cirugía, indicaciones de radioyodo y la supresión de la hormona estimulante de la tiroides. La correcta evaluación de los riesgos, antes y después de la cirugía, facilita un selectivo enfoque del tratamiento; destacando la relevancia de revisar el impacto de la medicina nuclear en la correcta evaluación, tratamiento y seguimiento de los pacientes que padecen esta neoplasia.Patients affected by differentiated thyroid cancer usually have a favorable clinical course, since the cornerstone of treatment is surgery; despite this, some patients may develop an ominous outcome, due to the clinical-pathological features of this disease. Optimal treatment remains controversial, especially regarding the extent of surgery, indications for radioiodine and thyroid-stimulating hormone. The correct evaluation of risks before and after surgery facilitates a selective treatment approach; highlighting the importance of reviewing the impact of nuclear medicine on the correct evaluation, treatment and follow-up of patients suffering from this neoplasm.


Assuntos
Radioisótopos do Iodo/administração & dosagem , Compostos Radiofarmacêuticos/administração & dosagem , Neoplasias da Glândula Tireoide/terapia , Humanos , Medicina Nuclear/métodos , Neoplasias da Glândula Tireoide/diagnóstico por imagem
14.
Cancer Biother Radiopharm ; 33(8): 316-329, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30265573

RESUMO

Scandium radionuclides have been identified in the late 1990s as promising for nuclear medicine applications, but have been set aside for about 20 years. Among the different isotopes of scandium, 43Sc and 44Sc are interesting for positron emission tomography imaging, whereas 47Sc is interesting for therapy. The 44Sc/47Sc or 43Sc/47Sc pairs could be thus envisaged as true theranostic pairs. Another interesting aspect of scandium is that its chemistry is governed by the trivalent ion, Sc3+. When combined with its hardness and its size, it gives this element a lanthanide-like behavior. It is then also possible to use it in a theranostic approach in combination with 177Lu or other lanthanides. This article aims to review the progresses that have been made over the last decade on scandium isotope production and coordination chemistry. It also reviews the radiolabeling aspects and the first (pre) clinical studies performed.


Assuntos
Radioisótopos/química , Compostos Radiofarmacêuticos/química , Escândio/química , Lutécio/química , Medicina Nuclear/métodos , Tomografia por Emissão de Pósitrons/métodos , Cintilografia/métodos
15.
J Control Release ; 287: 177-193, 2018 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-30086338

RESUMO

INTRODUCTION: Drug delivery systems are entities designed to alter the biological behaviour of the pharmaceutical active ingredients that they carry in order to afford more beneficial biodistribution and safety profiles. Many problems currently faced by the field of nuclear medicine (e.g. developing new theranostic agents, utilizing multimodal imaging platforms and providing targeted delivery) can be facilitated by applying drug delivery systems to radiopharmaceuticals that have been proven successful in other medical fields. This review describes the advancements being made towards this goal. AREAS COVERED: All aspects of drug delivery systems (liposomes, nanoparticles, microspheres) in the field of nuclear medicine are discussed. Only systems with foreseen or confirmed clinical applications in nuclear medicine are discussed, not instances where nuclear imaging is merely a tool to evaluate the biodistribution of novel delivery technologies. CONCLUSION: Great advancements have been made with the development of novel systems incorporating nuclear entities in drug delivery systems, with the possibility of reshaping the nuclear medicine landscape. Nonetheless, translation from preclinical evaluations to clinical use is lacking and serious investment needs to be made towards this goal.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Compostos Radiofarmacêuticos/administração & dosagem , Compostos Radiofarmacêuticos/farmacocinética , Animais , Portadores de Fármacos/química , Humanos , Lipossomos/química , Nanopartículas/química , Medicina Nuclear/métodos , Nanomedicina Teranóstica/métodos , Distribuição Tecidual
17.
J Nucl Med ; 59(11): 1649-1654, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30072501

RESUMO

90Y radioembolization is an increasingly used treatment for both primary and metastatic malignancy in the liver. Understanding the biophysical properties, dosing concerns, and imaging appearance of this treatment is important for interventional radiologists and nuclear medicine physicians to provide important therapy. 90Y radioembolization is efficacious and safe, although the possibility of complications does exist. This article provides a comprehensive in-depth discussion about the indications for 90Y radioembolization, reviews the role of preprocedural angiography and 99mTc-macroaggregated albumin scans, illustrates different dosing techniques, compares and contrasts resin and glass microspheres, and describes potential complications.


Assuntos
Carcinoma Hepatocelular/secundário , Carcinoma Hepatocelular/terapia , Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/terapia , Medicina Nuclear/métodos , Angiografia/métodos , Carcinoma Hepatocelular/diagnóstico por imagem , Educação Médica Continuada , Embolização Terapêutica/efeitos adversos , Embolização Terapêutica/métodos , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Microesferas , Medicina Nuclear/educação , Compostos Radiofarmacêuticos/uso terapêutico , Dosagem Radioterapêutica , Tomografia Computadorizada com Tomografia Computadorizada de Emissão de Fóton Único/métodos , Agregado de Albumina Marcado com Tecnécio Tc 99m , Imagem Corporal Total/métodos , Radioisótopos de Ítrio/uso terapêutico
18.
Int J Radiat Oncol Biol Phys ; 102(4): 1117-1142, 2018 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-30064704

RESUMO

Radiomics is a recent area of research in precision medicine and is based on the extraction of a large variety of features from medical images. In the field of radiation oncology, comprehensive image analysis is crucial to personalization of treatments. A better characterization of local heterogeneity and the shape of the tumor, depicting individual cancer aggressiveness, could guide dose planning and suggest volumes in which a higher dose is needed for better tumor control. In addition, noninvasive imaging features that could predict treatment outcome from baseline scans could help the radiation oncologist to determine the best treatment strategies and to stratify patients as at low risk or high risk of recurrence. Nuclear medicine molecular imaging reflects information regarding biological processes in the tumor thanks to a wide range of radiotracers. Many studies involving 18F-fluorodeoxyglucose positron emission tomography suggest an added value of radiomics compared with the use of conventional PET metrics such as standardized uptake value for both tumor diagnosis and prediction of recurrence or treatment outcome. However, these promising results should not hide technical difficulties that still currently prevent the approach from being widely studied or clinically used. These difficulties mostly pertain to the variability of the imaging features as a function of the acquisition device and protocol, the robustness of the models with respect to that variability, and the interpretation of the radiomic models. Addressing the impact of the variability in acquisition and reconstruction protocols is needed, as is harmonizing the radiomic feature calculation methods, to ensure the reproducibility of studies in a multicenter context and their implementation in a clinical workflow. In this review, we explain the potential impact of positron emission tomography radiomics for radiation therapy and underline the various aspects that need to be carefully addressed to make the most of this promising approach.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Medicina Nuclear/métodos , Radioterapia , Humanos , Neoplasias/diagnóstico por imagem , Neoplasias/radioterapia , Tomografia por Emissão de Pósitrons , Resultado do Tratamento
19.
Theranostics ; 8(13): 3559-3570, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30026866

RESUMO

Molecular imaging of the immune checkpoint receptor PD-1 and its ligand PD-L1 is increasingly investigated as a strategy to guide and monitor PD-1:PD-L1-targeted immune checkpoint therapy. We provide an overview of the current state-of-the-art on PD-1- and PD-L1-specific imaging agents for quantitative, real-time assessment of PD-1:PD-L1 expression in the tumor environment and discuss their potential for clinical translation.


Assuntos
Antígeno B7-H1/análise , Imagem Molecular/métodos , Neoplasias/diagnóstico , Medicina Nuclear/métodos , Medicina de Precisão/métodos , Receptor de Morte Celular Programada 1/análise , Humanos
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