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1.
J Clin Densitom ; 19(3): 266-9, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26670626

RESUMO

Both radiologists as well as nonimaging physicians perform dual-energy X-ray absorptiometry (DXA) imaging in the United States. This study aims to compare provider distribution between these physician groups on the Medicare population, which is the predominant age group of patients evaluated by this imaging procedure. Using the 2 relevant Current Procedural Terminology, Fourth Edition codes for DXA scans, source data were obtained from the CMS Physician Supplier Procedure Summary Master Files from 2003 through 2013. DXA scan procedure volumes for radiologists and nonradiologists on Medicare patients were tabulated. Utilization rates were calculated. From 2003 to 2013, the total number of DXA scans performed on Medicare patients decreased by 2%. However, over the same period, the number of scans performed by radiologists had increased by 25% over nonimaging specialists, whose utilization had declined by approximately the same amount. From 2003 to 2013, the rate of utilization of DXA scans in the Medicare fee-for-service population declined somewhat. However, radiologists continue to gain market share from other specialists and now predominate in this type of imaging by a substantial margin.


Assuntos
Absorciometria de Fóton/tendências , Osteoporose/diagnóstico por imagem , Padrões de Prática Médica/tendências , Radiologistas/tendências , Absorciometria de Fóton/estatística & dados numéricos , Humanos , Medicare , Médicos/tendências , Estados Unidos
2.
J Nucl Med ; 63(12): 1887-1890, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35552246

RESUMO

To our knowledge, no prior multicenter clinical trial has reported interobserver agreement of 18F-FDG PET/CT scans for staging of clinical N0 neck in head and neck cancer. Methods: A total of 287 participants were recruited. For visual analysis, positive nodal uptake of 18F-FDG was defined as uptake visually greater than activity seen in the blood pool. Results: The negative predictive value of the 18F-FDG PET/CT for N0 clinical neck was 86% or above for visual assessment (95% CI, 86%-88%) for the 2 central readers and above 90% (95% CI, 90%-95%) for SUVmax for central reads and site reads dichotomized at the optimal cutoff value of 1.8 and the prespecified cutoff value of 3.5, respectively. The κ coefficients between the 2 expert readers and between central reads and site reads varied between 0.53 and 0.78. Conclusion: The NPV of the 18F-FDG PET/CT for N0 clinical neck was 86% or above for visual assessment and above 90% for SUVmax cut points of 1.8 and 3.5 with moderate to substantial agreements.


Assuntos
Fluordesoxiglucose F18 , Neoplasias de Cabeça e Pescoço , Humanos , Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Estadiamento de Neoplasias , Variações Dependentes do Observador , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Compostos Radiofarmacêuticos , Tomografia Computadorizada por Raios X/métodos
3.
Radiographics ; 29(4): 1125-35, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19605661

RESUMO

Lymphoscintigraphy has become part of the standard of care for patients with a new or recurrent diagnosis of melanoma, in helping determine the status of regional lymph nodes. Correct identification of sentinel lymph nodes enables the surgeon to further delineate the extent of malignancy by allowing sampling of the appropriate nodal group. Performing the lymphoscintigraphy prior to the planned operation allows limited surgery with less extensive postoperative morbidity. For this reason, a thorough knowledge of the lymph node drainage patterns from the different primary tumor locations, as well as of proper lymphoscintigraphic techniques and radiopharmaceuticals, constitutes an important armamentarium in the hands of surgeons, radiologists, and nuclear medicine physicians.


Assuntos
Linfonodos/diagnóstico por imagem , Melanoma/diagnóstico por imagem , Melanoma/secundário , Biópsia de Linfonodo Sentinela/métodos , Neoplasias Cutâneas/diagnóstico por imagem , Tomografia Computadorizada de Emissão/métodos , Imagem Corporal Total/métodos , Humanos , Linfonodos/patologia , Melanoma/patologia , Modelos Anatômicos , Neoplasias Cutâneas/patologia
4.
J Am Coll Radiol ; 16(8): 1013-1017, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31092340

RESUMO

PURPOSE: The aim of this study was to analyze the utilization of elective stress nuclear myocardial perfusion imaging (MPI) in the Medicare population. METHODS: Nationwide Medicare Part B fee-for-service databases for 2004 to 2016 were reviewed. Current Procedural Terminology codes for stress MPI were selected: standard planar and single-photon emission computed tomography (STD) and PET. Utilization rates per 1,000 Medicare beneficiaries were calculated. Elective examinations were identified using place-of-service codes for private offices and hospital outpatient departments (HOPDs). Medicare physician specialty codes identified the performing physician. Because Medicare Part B databases are complete population counts, sample statistics were not required. RESULTS: Elective STD MPI utilization peaked in 2006 at 74 studies/1,000 and had declined by 36% by 2016. Cardiologists' share of STD MPI grew from 79% to 87% between 2004 and 2016. Cardiologists perform STD MPI primarily in private offices, where utilization peaked in 2008 and then demonstrated an absolute decline of 28 studies/1,000 by 2016. During this same time period, cardiologists' use of STD MPI in HOPDs demonstrated an absolute increase of 8.1 studies/1,000. From 2004 to 2016, STD MPI use by radiologists declined by 58%. Elective PET MPI maintained an upward trend, reflecting increasing use by cardiologists in private offices. CONCLUSIONS: Elective STD MPI use is declining, but cardiologists are performing an increasing share in outpatient settings. The drop in private office STD MPI among cardiologists was far greater than the corresponding increase in its use in HOPDs, suggesting that many studies previously performed in private offices were unindicated. Self-referred PET MPI utilization has rapidly grown in cardiology private offices.


Assuntos
Imagem de Perfusão do Miocárdio/tendências , Padrões de Prática Médica/tendências , Revisão da Utilização de Recursos de Saúde , Idoso , Current Procedural Terminology , Planos de Pagamento por Serviço Prestado , Pesquisa sobre Serviços de Saúde , Humanos , Medicare , Medicare Part B , Estados Unidos
5.
Nucl Med Commun ; 40(5): 455-460, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30855542

RESUMO

BACKGROUND: Radioactive iodine-131 (RAI) is an established treatment for patients with Graves' hyperthyroidism. RAI is reported to be associated with a 20-30% incidence of development or exacerbation of Graves' ophthalmopathy (GO). This study compares the progression of GO in patients who had evidence or no evidence of GO before RAI therapy. PATIENTS AND METHODS: Forty-eight patients were studied. One group had no evidence whereas the other group had evidence of GO before RAI treatment. All underwent RAI therapy. Group A (27 patients, 18 women, nine men, age: 19-68 with a mean of 49 years) had pre-existing exophthalmos. Group B consisted of 21 patients (13 women, eight men, age: 30-63 with a mean of 43 years) developed exophthalmos after treatment. All patients underwent RAI therapy and followed by ophthalmologists. RESULTS: The average administered dose in group A was 24.3 mCi (range: 10-36.2 mCi) compared with group B: 25.4 mCi (range: 13-35.9 mCi), P=0.60. Ten (37%) of the 27 patients in group A experienced worsening of symptoms post-treatment. There was no significant difference between the administered dose of RAI in patients with worsening symptoms, 25.1 mCi versus patients with stable symptoms, 24.5 mCi (P=0.82). However, group A developed GO symptoms earlier than group B (4.5 vs. 9.5 months), P=0.02. CONCLUSION: RAI is known to exacerbate ophthalmopathy. Our study showed it was not dose-dependent. Patients without a previous history of GO were observed to have a significantly delayed period for the development of symptoms.


Assuntos
Oftalmopatia de Graves/etiologia , Radioisótopos do Iodo/efeitos adversos , Adulto , Idoso , Relação Dose-Resposta à Radiação , Feminino , Humanos , Hipertireoidismo/radioterapia , Incidência , Radioisótopos do Iodo/uso terapêutico , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
6.
Eur J Surg Oncol ; 45(11): 2090-2095, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31253543

RESUMO

BACKGROUND: We sought to identify treatment disparities existing prior to publication of the 2015 American Thyroid Association Management Guidelines in order to identify patients with papillary thyroid cancer (PTC) at risk for receiving inadequate treatment. METHODS: Patients diagnosed with PTC from 2011 to 2013 were identified using Surveillance, Epidemiology and End Results database. High-risk disease was defined as T4, N1, or M1. Chi-square tests compared characteristics of patients with and without high-risk disease and characteristics of high-risk patients who did and did not receive radioactive iodine ablation (RAI). Likelihoods of having high-risk disease, of receiving RAI, and of cause-specific death were calculated using regression analyses. RESULTS: Sample included 32,229 individuals; 7894 (24.5%) had high-risk disease. Mean age was 50.0 years, 24,815 (77.0%) were female, and 21,318 (66.2%) were white. Odds of high-risk disease were greater among males (OR:2.04; 95% CI:1.92-2.16), Hispanics (OR:1.67; 95% CI:1.56-1.79) and Asians (OR:1.49; 95% CI:1.37-1.62), and uninsured (OR:1.24; 95% CI:1.07-1.43), and lower among patients ages 45-64 (OR:0.57; 95% CI:0.53-0.60), and ≥65 years (OR:0.54; 95% CI:0.50-0.59), and Blacks (OR:0.46; 95% CI:0.40-0.53). Most (69.3%) high-risk patients received RAI. Odds of receiving RAI were lower among patients age ≥65 years (OR:0.67; 95% CI:0.58-0.77), uninsured (OR:0.52; 95% CI:0.41-0.67), or with Medicaid (OR:0.58; 95% CI:0.50-0.69). RAI use reduced the risk of cause-specific mortality (HR:0.29; 95% CI:0.18-0.47). CONCLUSION: Knowledge of these treatment disparities will allow recognition of groups at risk for high-risk disease and receiving inadequate treatment.


Assuntos
Disparidades em Assistência à Saúde/estatística & dados numéricos , Radioisótopos do Iodo/uso terapêutico , Esvaziamento Cervical , Padrões de Prática Médica/estatística & dados numéricos , Câncer Papilífero da Tireoide/radioterapia , Neoplasias da Glândula Tireoide/radioterapia , Tireoidectomia , Adulto , Negro ou Afro-Americano/estatística & dados numéricos , Fatores Etários , Idoso , Asiático/estatística & dados numéricos , Etnicidade/estatística & dados numéricos , Feminino , Disparidades em Assistência à Saúde/etnologia , Hispânico ou Latino/estatística & dados numéricos , Humanos , Modelos Logísticos , Masculino , Medicaid/estatística & dados numéricos , Pessoas sem Cobertura de Seguro de Saúde/estatística & dados numéricos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Razão de Chances , Modelos de Riscos Proporcionais , Radioterapia Adjuvante/estatística & dados numéricos , Risco , Programa de SEER , Fatores Sexuais , Câncer Papilífero da Tireoide/mortalidade , Câncer Papilífero da Tireoide/patologia , Neoplasias da Glândula Tireoide/mortalidade , Neoplasias da Glândula Tireoide/patologia , Estados Unidos , População Branca/estatística & dados numéricos
7.
Surg Oncol Clin N Am ; 17(1): 197-218, x, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18177807

RESUMO

Survival from differentiated thyroid carcinoma is generally good, but postoperative management plays an important role in minimizing the likelihood of disease recurrence. Postoperative management is generally performed by endocrinologists and nuclear medicine physicians, who exploit thyroid cells' inherent iodineavidity and sensitivity to hormonal manipulation in a unique cancer management paradigm. Endocrinologists manage thyroid hormone replacement/thyroid stimulating hormone suppression and coordinate surveillance. Nuclear physicians administer targeted therapy with radioactive iodine and perform imaging studies to assess disease status. This article provides an overview of the postoperative assessment, treatment, and follow-up of patients who have thyroid carcinoma.


Assuntos
Cuidados Pós-Operatórios , Neoplasias da Glândula Tireoide/cirurgia , Humanos , Compostos de Iodo , Recidiva Local de Neoplasia , Radioisótopos , Radioterapia , Medição de Risco , Neoplasias da Glândula Tireoide/diagnóstico , Neoplasias da Glândula Tireoide/patologia
8.
J Nucl Med Technol ; 46(2): 144-146, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29438010

RESUMO

The Internet is a major source of health care information for patients. The American Medical Association and the National Institutes of Health recommend that consumer health care websites be written at a third- to seventh-grade level. The purpose of this study was to evaluate the level of readability of patient education websites pertaining to nuclear medicine. Methods: We searched for 10 terms on Google, collected the top 10 links for each term, and analyzed their level of readability using 10 well-established readability scales. Results: Collectively, the 99 articles were written at a grade level of 11.8 (SD, 3.4). Only 5 of the 99 articles were written at the third- to seventh-grade level recommended by the National Institutes of Health and the American Medical Association. Conclusion: There is a clear discordance between the readability level of nuclear medicine-related imaging terms and the National Institutes of Health and American Medical Association guidelines. This discordance may have a negative impact on patient understanding, contributing to poor health outcomes.


Assuntos
Medicina Nuclear/educação , Sistemas On-Line , Educação de Pacientes como Assunto/métodos , Humanos
9.
Radiographics ; 27(5): 1355-69, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17848696

RESUMO

Radionuclide imaging is often used in the diagnosis and work-up of a wide range of neoplasms, on the basis of the biologic behavior of the tumor. Neuroendocrine tumors are a subgroup of neoplasms that are generally small and slow growing, and consequently their identification with conventional anatomic imaging can be difficult. Depending on the physiologic properties of the tumor, functional images obtained with radionuclides are often complementary to anatomic images, not only in the localization of the tumor and its metastases, but also in the assessment of prognosis and response to therapy. Familiarity with the choice of the appropriate radiopharmaceutical, proper imaging protocols, and the wide range of imaging patterns will enable the radiologist to guide the clinician in case management.


Assuntos
Tumores Neuroendócrinos/diagnóstico por imagem , Tomografia Computadorizada de Emissão/métodos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Guias de Prática Clínica como Assunto , Padrões de Prática Médica
10.
Ultrasound Q ; 22(4): 231-8; discussion 239-40, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17146329

RESUMO

The Society of Radiologists in Ultrasound convened a panel of specialists from a variety of medical disciplines to come to a consensus on the management of thyroid nodules identified with thyroid ultrasonography (US), with particular focus on which nodules should be subjected to US-guided fine needle aspiration and which thyroid nodules need not be subjected to fine-needle aspiration. The panel met in Washington, DC, October 26-27, 2004, and created this consensus statement. The recommendations in this consensus statement, which are based on analysis of the current literature and common practice strategies, are thought to represent a reasonable approach to thyroid nodular disease.

11.
Clin Nucl Med ; 31(11): 673-8, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17053382

RESUMO

The lungs are among the most common sites for metastases from a multitude of cancers. The majority of pulmonary metastases appear nodular on radiologic images. Interstitial spread of tumor through pulmonary lymphatics, also known as pulmonary lymphangitic carcinomatosis (PLC), is not uncommon and constitutes approximately 7% of pulmonary metastases. PLC is most often seen with adenocarcinoma of a variety of histologies such as thyroid carcinoma, and melanoma. It is usually noted in late stages of malignancy and therefore is indicative of a poor prognosis. Diagnosis of PLC is usually based on a combination of clinical and radiologic findings. However, the diagnosis is difficult when patients have limited clinical findings or have a history of or the possibility of other interstitial lung diseases. High-resolution computed tomography (HRCT) has been the modality of choice in the radiologic diagnosis of PLC. Imaging features of PLC on HRCT include thickening of interlobular septa, fissures, and bronchovascular bundles. Distribution of PLC may be focal or diffuse, unilateral or bilateral, and symmetric or asymmetric. Although FDG-PET has been extensively used in primary or secondary lung malignancies, its role and appearance in PLC have not been well determined in the literature. In this communication, we describe a spectrum of FDG-PET and CT findings in 5 cases with PLC. Similar to CT, the distribution of PLC can be extensive or limited on the FDG-PET. Diffuse, lobar, or segmental FDG uptake in the lungs is seen in extensive PLC. In limited PLC, a linear or a hazy area of FDG uptake extending from the tumor can be seen. Recognition of various patterns related to PLC on FDG-PET may allow accurate diagnosis of disease and could potentially influence the management of these patients.


Assuntos
Carcinoma/diagnóstico por imagem , Carcinoma/secundário , Fluordesoxiglucose F18 , Aumento da Imagem/métodos , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/secundário , Pulmão/diagnóstico por imagem , Linfonodos/diagnóstico por imagem , Tomografia por Emissão de Pósitrons/métodos , Idoso , Feminino , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Compostos Radiofarmacêuticos
12.
Case Rep Pancreat Cancer ; 2(1): 36-39, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-30631813

RESUMO

Background: In the literature, pancreatic cancer is not frequently acknowledged among the tumors that are considered a part of Lynch Syndrome. Case Presentation: Our case is one of a young man who was found, very early in life, to have pancreatic cancer. His tumor demonstrated germline microsatellite instability, and hence by definition the patient has Lynch syndrome. He responded well to treatment, which included surgery and adjuvant chemotherapy. To date he remains in remission from pancreatic cancer. Conclusion: The rare instances in this case report include: (a) The patient had pancreatic cancer that fulfilled the histopathological and clinical criteria for Lynch syndrome. (b) Pancreatic cancer was diagnosed earlier in our patient than is expected in patients who suffer from pancreatic cancer as a part of Lynch syndrome. (c) Our patient had an excellent response to chemotherapy. He remains in remission to date from pancreatic cancer and is 5 years since his last treatment for this disease.

13.
PLoS One ; 11(6): e0157602, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27309537

RESUMO

BACKGOUND: The purpose of this study was to assess the biological and clinical effects of n-acetyl-cysteine (NAC) in Parkinson's disease (PD). METHODS: The overarching goal of this pilot study was to generate additional data about potentially protective properties of NAC in PD, using an in vitro and in vivo approach. In preparation for the clinical study we performed a cell tissue culture study with human embryonic stem cell (hESC)-derived midbrain dopamine (mDA) neurons that were treated with rotenone as a model for PD. The primary outcome in the cell tissue cultures was the number of cells that survived the insult with the neurotoxin rotenone. In the clinical study, patients continued their standard of care and were randomized to receive either daily NAC or were a waitlist control. Patients were evaluated before and after 3 months of receiving the NAC with DaTscan to measure dopamine transporter (DAT) binding and the Unified Parkinson's Disease Rating Scale (UPDRS) to measure clinical symptoms. RESULTS: The cell line study showed that NAC exposure resulted in significantly more mDA neurons surviving after exposure to rotenone compared to no NAC, consistent with the protective effects of NAC previously observed. The clinical study showed significantly increased DAT binding in the caudate and putamen (mean increase ranging from 4.4% to 7.8%; p<0.05 for all values) in the PD group treated with NAC, and no measurable changes in the control group. UPDRS scores were also significantly improved in the NAC group (mean improvement of 12.9%, p = 0.01). CONCLUSIONS: The results of this preliminary study demonstrate for the first time a potential direct effect of NAC on the dopamine system in PD patients, and this observation may be associated with positive clinical effects. A large-scale clinical trial to test the therapeutic efficacy of NAC in this population and to better elucidate the mechanism of action is warranted. TRIAL REGISTRATION: ClinicalTrials.gov NCT02445651.


Assuntos
Acetilcisteína/uso terapêutico , Antioxidantes/uso terapêutico , Fármacos Neuroprotetores/uso terapêutico , Neurotoxinas/antagonistas & inibidores , Doença de Parkinson/tratamento farmacológico , Rotenona/antagonistas & inibidores , Idoso , Núcleo Caudado/diagnóstico por imagem , Núcleo Caudado/efeitos dos fármacos , Núcleo Caudado/metabolismo , Núcleo Caudado/patologia , Diferenciação Celular , Sobrevivência Celular/efeitos dos fármacos , Dopamina/metabolismo , Proteínas da Membrana Plasmática de Transporte de Dopamina/metabolismo , Neurônios Dopaminérgicos/citologia , Neurônios Dopaminérgicos/efeitos dos fármacos , Neurônios Dopaminérgicos/metabolismo , Feminino , Células-Tronco Embrionárias Humanas/citologia , Células-Tronco Embrionárias Humanas/metabolismo , Humanos , Masculino , Mesencéfalo/diagnóstico por imagem , Mesencéfalo/efeitos dos fármacos , Mesencéfalo/metabolismo , Mesencéfalo/patologia , Pessoa de Meia-Idade , Neurotoxinas/toxicidade , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/metabolismo , Doença de Parkinson/patologia , Projetos Piloto , Putamen/diagnóstico por imagem , Putamen/efeitos dos fármacos , Putamen/metabolismo , Putamen/patologia , Rotenona/toxicidade , Tomografia Computadorizada com Tomografia Computadorizada de Emissão de Fóton Único , Técnicas de Cultura de Tecidos
14.
Semin Nucl Med ; 35(4): 257-65, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16150246

RESUMO

The management of patients with differentiated thyroid cancer has changed significantly over the last few decades. Mortality has decreased as the result of earlier detection, refined surgical approaches, subsequent radioiodine ablation, and the development of more sensitive methods for detecting and monitoring disease recurrence. The latter has been facilitated by serum thyroglobulin measurements, the use of recombinant human thyrotropin, and the use of 18F-deoxyglucose/positron emission tomography in selected instances where radioiodine imaging fails to locate known or suspected recurrent or metastatic disease.


Assuntos
Radioisótopos do Iodo/uso terapêutico , Recidiva Local de Neoplasia/diagnóstico , Recidiva Local de Neoplasia/prevenção & controle , Tireoglobulina/sangue , Neoplasias da Glândula Tireoide/diagnóstico , Neoplasias da Glândula Tireoide/terapia , Tireoidectomia/métodos , Humanos , Guias de Prática Clínica como Assunto , Padrões de Prática Médica/tendências , Compostos Radiofarmacêuticos/uso terapêutico , Neoplasias da Glândula Tireoide/sangue , Resultado do Tratamento
15.
Clin Nucl Med ; 30(6): 400-7, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15891292

RESUMO

Chronic pain resulting from complex regional pain syndrome type I (CRPS I), formerly referred to as the reflex sympathetic dystrophy syndrome (RSDS), is a diagnostic challenge to the clinician. It involves multiple organ systems, namely peripheral as well as central nervous, vascular, soft tissue, and skeletal. It usually develops as a consequence of trauma, without nerve injury. Signs and symptoms vary depending on the time since the initiating event, and there is no confirmatory histopathologic diagnosis. This article summarizes the current consensus on the classification, pathophysiology, and diagnostic approaches, emphasizing the role of scintigraphy in the management of this multisystem disorder.


Assuntos
Doenças Ósseas/complicações , Doenças Ósseas/diagnóstico por imagem , Encefalopatias/complicações , Encefalopatias/diagnóstico por imagem , Medicina Nuclear/métodos , Distrofia Simpática Reflexa/diagnóstico por imagem , Distrofia Simpática Reflexa/etiologia , Humanos , Guias de Prática Clínica como Assunto , Padrões de Prática Médica , Cintilografia , Distrofia Simpática Reflexa/terapia , Índice de Gravidade de Doença
16.
Eur J Cancer ; 51(14): 1857-64, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26187510

RESUMO

BACKGROUND: For patients with metastatic pancreatic adenocarcinoma, there are no approved or established treatments beyond the 2nd line. A Phase Ib study of fractionated radioimmunotherapy was undertaken in this setting, administering (90)Y-clivatuzumab tetraxetan (yttrium-90-radiolabelled humanised antibody targeting pancreatic adenocarcinoma mucin) with or without low radiosensitising doses of gemcitabine. METHODS: Fifty-eight patients with three (2-7) median prior treatments were treated on Arm A (N=29, (90)Y-clivatuzumab tetraxetan, weekly 6.5 mCi/m(2)doses×3, plus gemcitabine, weekly 200 mg/m(2) doses×4 starting 1 week earlier) or Arm B (N=29, (90)Y-clivatuzumab tetraxetan alone, weekly 6.5 mCi/m(2)doses×3), repeating cycles after 4-week delays. Safety was the primary endpoint; efficacy was also evaluated. RESULTS: Cytopaenias (predominantly transient thrombocytopenia) were the only significant toxicities. Fifty-three patients (27 Arm A, 26 Arm B, 91% overall) completed ⩾1 full treatment cycles, with 23 (12 Arm A, 11 Arm B; 40%) receiving multiple cycles, including seven (6 Arm A, 1 Arm B; 12%) given 3-9 cycles. Two patients in Arm A had partial responses by RECIST criteria. Kaplan-Meier overall survival (OS) appeared improved in Arm A versus B (hazard ratio [HR] 0.55, 95% CI: 0.29-0.86; P=0.017, log-rank) and the median OS for Arm A versus Arm B increased to 7.9 versus 3.4 months with multiple cycles (HR 0.32, P=0.004), including three patients in Arm A surviving >1 year. CONCLUSIONS: Clinical studies of (90)Y-clivatuzumab tetraxetan combined with low-dose gemcitabine appear feasible in metastatic pancreatic cancer patients beyond 2nd line and a Phase III trial of this combination is now underway in this setting.


Assuntos
Adenocarcinoma/terapia , Anticorpos Monoclonais/uso terapêutico , Antimetabólitos Antineoplásicos/administração & dosagem , Desoxicitidina/análogos & derivados , Neoplasias Pancreáticas/terapia , Radioimunoterapia/métodos , Compostos Radiofarmacêuticos/uso terapêutico , Radioisótopos de Ítrio/uso terapêutico , Adenocarcinoma/imunologia , Adenocarcinoma/mortalidade , Adenocarcinoma/secundário , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais/efeitos adversos , Antimetabólitos Antineoplásicos/efeitos adversos , Quimioterapia Adjuvante , Desoxicitidina/administração & dosagem , Desoxicitidina/efeitos adversos , Progressão da Doença , Estudos de Viabilidade , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Mucinas/imunologia , Neoplasias Pancreáticas/imunologia , Neoplasias Pancreáticas/mortalidade , Neoplasias Pancreáticas/patologia , Radioimunoterapia/efeitos adversos , Radioimunoterapia/mortalidade , Compostos Radiofarmacêuticos/efeitos adversos , Indução de Remissão , Trombocitopenia/induzido quimicamente , Fatores de Tempo , Resultado do Tratamento , Estados Unidos , Radioisótopos de Ítrio/efeitos adversos , Gencitabina
17.
Radiographics ; 23(4): 857-69, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12853661

RESUMO

The term thyrotoxicosis refers to the clinical syndrome of increased systemic metabolism that results when the serum concentrations of free thyroxine, free triiodothyronine, or both are elevated. The term hyperthyroidism refers to overactivity of the thyroid gland with a resultant increase in thyroid hormone synthesis and release into the systemic circulation. These terms are not interchangeable, since thyrotoxicosis can develop in thyroid conditions that are not associated with increased thyroid function, such as thyroiditis, or in so-called factitious hyperthyroidism. The clinical signs and symptoms of thyrotoxicosis are virtually identical regardless of the cause. However, in a given patient, every attempt should be made to determine the exact cause of the thyrotoxicosis, as this in turn determines the prognosis and treatment. Since thyroid scintigraphy demonstrates the functional state of the thyroid gland, it should be used, in conjunction with determination of radioactive iodine uptake, as the imaging modality of choice for diagnosis of thyrotoxicosis. Although the scintigraphic features of several of the thyroid disorders that cause thyrotoxicosis may overlap, their recognition helps narrow the differential diagnosis, thereby guiding the referring physician in the work-up and management of this disorder.


Assuntos
Cintilografia/métodos , Tireotoxicose/diagnóstico por imagem , Tireotoxicose/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
18.
J Am Coll Radiol ; 10(3): 198-201, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23571060

RESUMO

PURPOSE: The aims of this study were to examine recent trends in the utilization of radionuclide myocardial perfusion imaging (MPI) and to reflect on their causes and their implications for radiologists. METHODS: Nationwide Medicare Part B databases for 2000 through 2010 were used. Codes for primary MPI studies (including PET) were selected. Medicare specialty codes were used to identify MPI examinations done by radiologists, cardiologists, and other physicians. Place-of-service codes were used to identify examinations performed in offices versus hospital settings. Utilization rates per 1,000 fee-for-service beneficiaries were calculated. Trends were assessed by place of service and specialty. RESULTS: The overall MPI utilization rate rose from 2000 through 2004, followed by a period of stabilization from 2005 to 2008. A peak of 88.0 per 1,000 was reached in 2006. In 2009 and 2010, a decline occurred, with the rate dropping by 13% to 76.9. In private offices, cardiologists' utilization grew rapidly from 2000 through 2006, but growth stopped thereafter. Their rate peaked in 2008 at 50.6 but dropped to 44.4 by 2010 (-12%). Radiologists' role in office MPI was minimal. In hospital settings, radiologists predominated in 2000. Their rate remained stable through 2004 but thereafter began to decline steadily, dropping by 35% by 2010. Cardiologists' hospital-based utilization rate rose gradually, then flattened, but began to rise in 2009 and 2010. By 2010, cardiologists performed more hospital MPI examinations than radiologists. CONCLUSIONS: Radiologists' initially predominant role in hospital-based MPI has eroded recently, while that of cardiologists has strengthened. This seems related to a shift among cardiologists away from office practice and into hospital affiliations.


Assuntos
Cardiologia/economia , Medicare Part B/economia , Imagem de Perfusão do Miocárdio/economia , Imagem de Perfusão do Miocárdio/estatística & dados numéricos , Padrões de Prática Médica/economia , Mecanismo de Reembolso/economia , Codificação Clínica , Planos de Pagamento por Serviço Prestado/economia , Humanos , Estados Unidos
19.
Melanoma Res ; 23(1): 33-9, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23164993

RESUMO

As uveal melanoma originates in the neural crest, we aimed to explore whether somatostatin receptor (SSTR) expression is present and plays any role in these patients. Heavily pretreated metastatic uveal melanoma patients were tested with somatostatin receptor scintigraphy (SRS). Planar images of the whole body complemented by single-photon emission computed tomography on suspected sites were acquired between 4 and 24 h after an intravenous administration of 185-222 MBq (5-6 mCi) of indium-octeotride. SSTR expression in metastatic tissues was confirmed by immunohistochemistry. In seven patients, sandostatin LAR was used with therapeutic intention. Thirty white patients were tested. All had extensive metastatic disease and the median number of previous treatments was three. SRS was found to be positive in 14 (46%) of the patients, but was not related to sex, type of previous treatments, tumor site, or histological type. In 10 patients, sufficient tumor specimens were available to perform immunohistochemical staining for SSTR. All cases with positive SSTR-2A staining were also positive by SRS. Two of the seven patients who received sandostatin LAR died within a month after receiving the first dose, whereas another two (28.5%) had stable disease for more than 5 months. The median time to progression after starting sandostatin was 2.1 months (range: 0.2-5.5 months). Approximately 50% of the uveal melanoma patients with extensive metastatic disease were positive for SSR, which was consistent with immunohistochemical staining for SSTR-2A. Therapeutic approaches targeting SSTR might be beneficial in patients with metastatic uveal melanoma.


Assuntos
Melanoma/diagnóstico por imagem , Melanoma/secundário , Receptores de Somatostatina/metabolismo , Neoplasias Uveais/diagnóstico por imagem , Neoplasias Uveais/patologia , Adulto , Idoso , Antineoplásicos/uso terapêutico , Feminino , Humanos , Radioisótopos de Índio , Masculino , Melanoma/tratamento farmacológico , Pessoa de Meia-Idade , Octreotida/análogos & derivados , Octreotida/uso terapêutico , Tomografia Computadorizada de Emissão de Fóton Único , Resultado do Tratamento , Neoplasias Uveais/tratamento farmacológico , Adulto Jovem
20.
J Nucl Med ; 54(7): 1019-25, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23651947

RESUMO

UNLABELLED: VPAC1 encodes G-protein-coupled receptors expressed on all breast cancer (BC) cells at the onset of the disease, but not on benign lesions. Our extensive preclinical studies have shown that (64)Cu-TP3805 has a high affinity for VPAC1, is stable in vivo, and has the ability to distinguish spontaneously grown malignant BC masses from benign lesions. Our long-term goal is to develop (64)Cu-TP3805 as an agent to perform in vivo histology, to distinguish malignant lesions from benign masses noninvasively and thereby avoid patient morbidity and the excess economic costs of benign biopsies. METHODS: (18)F-FDG obtained commercially served as a control. (64)Cu-TP3805 was prepared using a sterile kit containing 20 µg of TP3805. Radiochemical purity and sterility were examined. Nineteen consenting women with histologically proven BC were given 370 MBq of (18)F-FDG. One hour later, 6 of these patients were imaged with PET/CT and 13 with positron emission mammography (PEM). Two to 7 d later, 6 PET/CT patients received 111 MBq (± 10%) (n = 2), 127 MBq (± 10%) (n = 2), or 148 MBq (± 10%) (n = 2) of (64)Cu-TP3805 and were imaged 2 and 4 h later. Thirteen PEM patients received 148 MBq (± 10%) of (64)Cu-TP3805 and were imaged 15 min, 1 h, 2 h, and 4 h later. Standardized uptake value (SUV) was calculated for PET/CT patients, and PUV/BGV (PEM uptake value/background value) was calculated for PEM patients. Tumor volume was also calculated. RESULTS: The radiochemical purity of (64)Cu-TP3805 was 97% ± 2%, and specific activity was 44.4 GBq (1.2 Ci)/µmol. In 19 patients, a total of 24 lesions were imaged (15 invasive ductal carcinoma, 1 high-grade mammary carcinoma, 3 lobular carcinoma, 1 invasive papilloma, and 4 sentinel lymph nodes). All lesions were unequivocally detected by (64)Cu-TP3805 and by (18)F-FDG. The average tumor volume as determined by PET/CT with (64)Cu-TP3805 was 90.6% ± 16.1% of that with (18)F-FDG PET/CT, and the average SUV was 92% ± 26.4% of that with (18)F-FDG. For PEM, the tumor volume with (64)Cu-TP3805 was 113% ± 37% of that with (18)F-FDG and the PUV/BGV ratio was 97.7% ± 24.5% of that with (18)F-FDG. CONCLUSION: (64)Cu-TP3805 is worthy of further investigation in patients requiring biopsy of suggestive imaging findings, to further evaluate its ability to distinguish malignant lesions from benign masses noninvasively.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/metabolismo , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/farmacocinética , Receptores Tipo I de Polipeptídeo Intestinal Vasoativo/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Radioisótopos de Cobre/farmacocinética , Estudos de Viabilidade , Feminino , Humanos , Pessoa de Meia-Idade , Imagem Molecular/métodos , Cintilografia , Compostos Radiofarmacêuticos/farmacocinética , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
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