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1.
J Am Coll Cardiol ; 82(19): 1828-1838, 2023 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-37914512

RESUMO

BACKGROUND: GadaCAD2 was 1 of 2 international, multicenter, prospective, Phase 3 clinical trials that led to U.S. Food and Drug Administration approval of gadobutrol to assess myocardial perfusion and late gadolinium enhancement (LGE) in adults with known or suspected coronary artery disease (CAD). OBJECTIVES: A prespecified secondary objective was to determine if stress perfusion cardiovascular magnetic resonance (CMR) was noninferior to single-photon emission computed tomography (SPECT) for detecting significant CAD and for excluding significant CAD. METHODS: Participants with known or suspected CAD underwent a research rest and stress perfusion CMR that was compared with a gated SPECT performed using standard clinical protocols. For CMR, adenosine or regadenoson served as vasodilators. The total dose of gadobutrol was 0.1 mmol/kg body weight. The standard of reference was a 70% stenosis defined by quantitative coronary angiography (QCA). A negative coronary computed tomography angiography could exclude CAD. Analysis was per patient. CMR, SPECT, and QCA were evaluated by independent central core lab readers blinded to clinical information. RESULTS: Participants were predominantly male (61.4% male; mean age 58.9 ± 10.2 years) and were recruited from the United States (75.0%), Australia (14.7%), Singapore (5.7%), and Canada (4.6%). The prevalence of significant CAD was 24.5% (n = 72 of 294). Stress perfusion CMR was statistically superior to gated SPECT for specificity (P = 0.002), area under the receiver operating characteristic curve (P < 0.001), accuracy (P = 0.003), positive predictive value (P < 0.001), and negative predictive value (P = 0.041). The sensitivity of CMR for a 70% QCA stenosis was noninferior and nonsuperior to gated SPECT. CONCLUSIONS: Vasodilator stress perfusion CMR, as performed with gadobutrol 0.1 mmol/kg body weight, had superior diagnostic accuracy for diagnosis and exclusion of significant CAD vs gated SPECT.


Assuntos
Doença da Artéria Coronariana , Imagem de Perfusão do Miocárdio , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Peso Corporal , Constrição Patológica , Meios de Contraste , Angiografia Coronária/métodos , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/patologia , Gadolínio , Imageamento por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética , Imagem de Perfusão do Miocárdio/métodos , Perfusão , Valor Preditivo dos Testes , Estudos Prospectivos , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Vasodilatadores
2.
Breast Cancer (Auckl) ; 16: 11782234221092155, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35462754

RESUMO

Background: The impact of certain tumor parameters on the sensitivity of imaging tools is unknown. The purpose was to study the impact of breast cancer histology, tumor grading, single receptor status, and molecular subtype on the sensitivity of contrast-enhanced breast magnetic resonance imaging (CE-BMRI) vs X-ray mammography (XRM) to detect breast cancer. Materials and Methods: We ran a supplemental analysis of 2 global Phase III studies which recruited patients with histologically proven breast cancers. The sensitivity of CE-BMRI vs XRM to detect cancer lesions with different histologies, tumor grading, single receptor status, and molecular subtype was compared. Six blinded readers for each study evaluated the images. Results were summarized as the "Mean Reader." For each reader, sensitivity was defined as the proportion of detected lesions vs the total number of lesions identified by the standard of reference. Two-sided 95% confidence intervals were calculated for within-group proportions, and for the difference between CE-BMRI and XRM, using a normal approximation to the binomial distribution. Results: In 778 patients, 1273 cancer lesions were detected. A total of 435 patients had 1 lesion, 254 had 2 lesions, and 77 had 3 or more lesions. The sensitivity of CE-BMRI was significantly higher compared with XRM irrespective of the histology. The largest difference was seen for invasive lobular carcinoma (22.3%) and ductal carcinoma in situ (19%). Across all 3 tumor grades, the sensitivity advantage of CE-BMRI over XRM ranged from 15.7% to 18.5%. Contrast-enhanced breast magnetic resonance imaging showed higher sensitivity compared with XRM irrespective of single receptor expressions (15.3%-19.4%). The sensitivities for both imaging methods were numerically higher for the more aggressive ER- (estrogen receptor), PR- (progesterone receptor), and HER2+ (human epidermal growth factor receptor 2) tumors. Irrespective of molecular subtype, sensitivity of CE-BMRI was 14.8% to 18.9% higher compared with XRM. Conclusions: Contrast-enhanced breast magnetic resonance imaging showed significantly higher sensitivity compared with XRM independent of tumor histology, tumor grading, single receptor status, and molecular subtype.Trial Registration: ClinicalTrials.gov: NCT01067976 and NCT01104584.

3.
Acta Radiol ; 62(5): 586-593, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-32678675

RESUMO

BACKGROUND: Detection of breast cancer in women with high breast densities is a clinical challenge. PURPOSE: To study the influence of different degrees of breast density on the sensitivity of contrast-enhanced breast magnetic resonance imaging (CE-BMRI) versus X-ray mammography (XRM). MATERIAL AND METHODS: We performed an additional analysis of two large Phase III clinical trials (G1; G2) which included women with histologically proven breast cancers, called "index cancers." Additional cancers were detected during image reading. We compared the sensitivity of CE-BMRI and XRM in women with different breast densities (ACR A→D; Version 5). For each study, six blinded readers evaluated the images. Results are given as the "Median Reader." RESULTS: A total of 774 patients were included, 169 had additional cancers. While sensitivity of CE-BMRI for detecting all index cancers was independent of breast density (ACR A→D) (G1: 83%→83%; G2: 91%→91%) the sensitivity of XRM declined (ACR A→D) (G1: 79%→62%; G2: 82%→64%). Thus, the sensitivity difference between both imaging modalities in ACR A breasts of 3% (G1) and 9% (G2) increased to 21% (G1) and 26% (G2) in ACR D breasts. Sensitivity of CE-BMRI for detecting at least one additional cancer increased with increasing breast density (ACR A→D) (G1: 50%→73%, G2: 57%→81%). XRM's sensitivity decreased (G1: 34%→20%) or remained stable (G2: 24%→25%). CONCLUSION: CE-BMRI showed significantly higher sensitivity compared to XRM.


Assuntos
Densidade da Mama , Neoplasias da Mama/diagnóstico por imagem , Imageamento por Ressonância Magnética , Mamografia , Idoso , Meios de Contraste , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Pessoa de Meia-Idade , Sensibilidade e Especificidade
4.
J Magn Reson Imaging ; 47(2): 572-581, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28574637

RESUMO

PURPOSE: To compare the performance of magnetic resonance angiography (MRA) with 1M gadobutrol, a high relaxivity macrocyclic contrast agent, to 2D time-of-flight MRA (ToF-MRA) using computed tomographic angiography (CTA) as the standard of reference. Primary objectives were evaluation for superiority of structural delineation and noninferiority for detection and exclusion of clinically significant disease. MATERIALS AND METHODS: In all, 315 subjects underwent unenhanced and contrast-enhanced MRA with 1M gadobutrol (CE-MRA) and were scanned with 1.5T MRI equipped with an at least 6-element body coil. Evaluations were based on both centralized blinded read (BR) performed by six readers as well as investigator site interpretations for the 292 subjects who completed the study. Quantitative evaluations including percent stenosis and normal vessel measurements were also performed. Secondary endpoints included identification of accessory renal arteries, diagnosis of fibromuscular dysplasia (FMD), diagnostic confidence, and need for additional imaging. RESULTS: A total of 292 patients suspected of renal artery disease completed the study. CE-MRA demonstrated statistically significant improvement in assessability of vascular segments compared to ToF: 95.9% vs. 77.6% (P < 0.0001). In the BR, the sensitivity and specificity of CE-MRA were noninferior to ToF-MRA (53.4% vs. 46.6% and 95.1% vs. 85.7%, respectively). There was less error in the CE-MRA stenosis measurements (0.15 mm gadobutrol vs. 0.41 mm ToF, P < 0.05). FMD was correctly diagnosed more frequently, 10% more accessory renal arteries were identified (P < 0.01), diagnostic confidence increased (P < 0.01), and fewer additional imaging studies were recommended (P < 0.01). CONCLUSION: Gadobutrol-enhanced MRA of the renal arteries has superior visualization, more accurate vessel measurements, and may serve as a CTA alternative without any ionizing radiation. LEVEL OF EVIDENCE: 1 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2018;47:572-581.


Assuntos
Meios de Contraste , Aumento da Imagem/métodos , Angiografia por Ressonância Magnética/métodos , Compostos Organometálicos , Artéria Renal/diagnóstico por imagem , Doenças Vasculares/diagnóstico por imagem , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Método Simples-Cego , Adulto Jovem
5.
Invest Radiol ; 51(7): 454-61, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26840494

RESUMO

OBJECTIVES: The aim of this study was to evaluate the diagnostic efficacy of gadobutrol enhanced preoperative breast magnetic resonance imaging (MRI) in 2 prospective studies. MATERIALS AND METHODS: Approval of ethics committees and informed consent from patients were obtained. Both Gadobutrol-Enhanced MR Mammography (GEMMA) trials followed a standardized protocol using 1.5 T scanners. After unenhanced scans, patients received 0.1 mmol/kg of gadobutrol for the dynamic study. Six independent blinded readers, 3 for GEMMA1 and 3 for GEMMA2, assessed unenhanced images and, 2 or more weeks apart, contrast-enhanced plus unenhanced breast MRI images (CE-BMRI), using a standard 5-region scheme. Another 6 independent readers (3 for each study) evaluated mammograms alone. Sensitivity was calculated taking into account the identification of regions harboring malignancies (within-patient sensitivity), whereas specificity was based on cancer-free breasts. The first patient from each center was used for site qualification and blinded reader training and excluded from the efficacy analyses. Reference standard was pathology for regions harboring malignancy and a combination of negative pathology, mammography, and ultrasound for cancer-free regions. RESULTS: Of 906 breast cancer patients enrolled in 13 countries in the 2 studies, 865 received gadobutrol and 787 were evaluated for diagnostic performance (390 in GEMMA1 and 397 in GEMMA2). Within-patient sensitivity, that is, the detection rate of malignant disease extent per patient, ranged from 80% to 89% for CE-BMRI and was significantly superior to unenhanced breast MRI alone (37%-73%) and to mammography alone (68%-73%) for all readers in both trials. Specifity of the CE-BMRI ranged from 83% to 95%. CONCLUSION: In a very large multicenter preoperative setting, gadobutrol-enhanced breast MRI demonstrated high levels of sensitivity and specificity, consistent with published data on breast MRI.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Meios de Contraste , Aumento da Imagem/métodos , Imageamento por Ressonância Magnética/métodos , Compostos Organometálicos , Cuidados Pré-Operatórios/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Mama/diagnóstico por imagem , Feminino , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
6.
Magn Reson Insights ; 8: 1-10, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25922578

RESUMO

PURPOSE: Contrast-enhanced magnetic resonance imaging (MRI) of the central nervous system (CNS) with gadolinium-based contrast agents (GBCAs) is standard of care for CNS imaging and diagnosis because of the visualization of lesions that cause blood-brain barrier breakdown. Gadobutrol is a macrocyclic GBCA with high concentration and high relaxivity. The objective of this study was to compare the safety and efficacy of gadobutrol 1.0 M vs unenhanced imaging and vs the approved macrocyclic agent gadoteridol 0.5 M at a dose of 0.1 mmol/kg bodyweight. MATERIALS AND METHODS: Prospective, multicenter, double-blind, crossover trial in patients who underwent unenhanced MRI followed by enhanced imaging with gadobutrol or gadoteridol. Three blinded readers assessed the magnetic resonance images. The primary efficacy variables included number of lesions detected, degree of lesion contrast-enhancement, lesion border delineation, and lesion internal morphology. RESULTS: Of the 402 treated patients, 390 patients received study drugs. Lesion contrast-enhancement, lesion border delineation, and lesion internal morphology were superior for combined unenhanced/gadobutrol-enhanced imaging vs unenhanced imaging (P < 0.0001 for all). Compared with gadoteridol, gadobutrol was non-inferior for all primary variables and superior for lesion contrast-enhancement, as well as sensitivity and accuracy for detection of malignant disease. The percentage of patients with at least one drug-related adverse event was similar for gadobutrol (10.0%) and gadoteridol (9.7%). CONCLUSION: Gadobutrol is an effective and well-tolerated macrocyclic contrast agent for MRI of the CNS. Gadobutrol demonstrates greater contrast-enhancement and improved sensitivity and accuracy for detection of malignant disease than gadoteridol, likely because of its higher relaxivity.

7.
BJU Int ; 100(1): 51-7, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17552953

RESUMO

OBJECTIVE: To compare the clinical and bacteriological efficacy and the clinical safety of a 1-day with a 3-day regimen of an extended-release formulation of ciprofloxacin (ciprofloxacin XR) given as antimicrobial prophylaxis to men undergoing transrectal needle biopsy of the prostate (TRNBP). PATIENTS AND METHODS: This was a multicentre, prospective, international, double-blind study in patients who required TRNBP. Patients were randomized to receive oral ciprofloxacin XR 1000 mg as either a 1-day or a 3-day regimen. Single doses were given at 24 h before, 2-3 h before, and 24 h after TRNBP. Patients in the 1-day regimen had placebo instead of the first and third doses of ciprofloxacin. RESULTS: Of 497 patients enrolled, 247 were randomized to 1-day ciprofloxacin XR and 250 to the 3-day regimen. In the population valid for microbiological efficacy, the final assessment identified bacteriological success (primary efficacy endpoint) in more patients who had the 3-day regimen (98%) than in those who received the 1-day regimen (94.8%, 95% confidence interval, CI, - 6.1%, 0.8%), although the difference was not statistically significant. In this population, the clinical response at the final visit was 98.5% and 96.7% for patients receiving the 3-day and the 1-day regimens, respectively (95% CI - 5.2%, 0.8%). However, in the clinical efficacy population the clinical success rate was significantly greater for the 3-day (99.0%) than for the 1-day regimen (95.8%; 95% CI - 6.4%, - 0.3%). In a multivariate analysis, patients with diabetes mellitus and patients with a history of prostatitis had higher microbiological and clinical failure rates, respectively, than those without such conditions. For these patients, all failures occurred among those treated with the 1-day regimen. CONCLUSION: As defined by bacteriological success in the population assessed for microbiological efficacy, prophylaxis with one dose of ciprofloxacin XR was statistically no worse than a 3-day regimen. However, in all efficacy analyses, bacteriological and clinical success rates were consistently lower for the 1-day than for the 3-day treatment. Thus, for selected patients undergoing TRNBP, there might be a role for 3-day preventive therapy with ciprofloxacin XR.


Assuntos
Anti-Infecciosos/administração & dosagem , Infecções Bacterianas/prevenção & controle , Biópsia por Agulha/efeitos adversos , Ciprofloxacina/administração & dosagem , Próstata/patologia , Neoplasias da Próstata/patologia , Idoso , Preparações de Ação Retardada/administração & dosagem , Método Duplo-Cego , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Estudos Prospectivos , Neoplasias da Próstata/complicações , Fatores de Tempo , Resultado do Tratamento
8.
Ann Intern Med ; 137(2): 77-87, 2002 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-12118962

RESUMO

BACKGROUND: Therapy with an aminoglycoside and a beta-lactam remains common empirical therapy for febrile neutropenic patients. Concerns of aminoglycoside-induced ototoxicity and nephrotoxicity have led to studies of alternate regimens. OBJECTIVE: To determine whether ciprofloxacin-piperacillin is equivalent to tobramycin-piperacillin as empirical therapy for neutropenic fever. DESIGN: Randomized, double-blind multicenter trial. SETTING: Seven U.S. university-affiliated hospitals and one private research center. PATIENTS: Febrile (temperature >/= 38 degrees C), neutropenic (neutrophil level < 1 x 10(9) cells/L) hospitalized patients who had leukemia, lymphoma, or solid tumors, or were undergoing bone marrow transplantation. INTERVENTIONS: Patients received piperacillin, 50 mg/kg of body weight intravenously every 4 hours, and ciprofloxacin, 400 mg intravenously every 8 hours, or tobramycin, 2 mg/kg intravenously every 8 hours. MEASUREMENTS: Success was defined as resolution of infection and previously positive cultures without the need to give additional antimicrobial agents. RESULTS: 543 febrile episodes were evaluated, of which 471 were clinically evaluable (234 in the ciprofloxacin-piperacillin group and 237 in the tobramycin-piperacillin group). Success rates in the ciprofloxacin-piperacillin group (63 of 234 febrile episodes) and tobramycin-piperacillin group (52 of 237 episodes) were similar (27% vs. 22%, respectively; difference, 5.0 percentage points [95% CI, -2.3 to 12.8 percentage points]), as was survival (96.2% of patients receiving ciprofloxacin-piperacillin versus 94.1% of patients receiving tobramycin-piperacillin; difference, 2.1 percentage points [CI, -2.2 to 6.4 percentage points]). Additions to the initial antimicrobial regimen were the most common reason for treatment failure in both groups (accounting for 67% of failures in the ciprofloxacin-piperacillin group and 72% in the tobramycin-piperacillin group; difference, 5.0 percentage points [CI, -13.8 to 3.7 percentage points]). Fevers resolved faster in patients receiving ciprofloxacin-piperacillin than in patients receiving tobramycin-piperacillin (mean, 5 vs. 6 days) (P = 0.005). No significant differences in adverse events or toxicity were noted (P = 0.083). CONCLUSION: Ciprofloxacin-piperacillin is as safe and effective as tobramycin-piperacillin for empirical therapy of neutropenic fever.


Assuntos
Ciprofloxacina/uso terapêutico , Quimioterapia Combinada/uso terapêutico , Febre/tratamento farmacológico , Neutropenia/tratamento farmacológico , Piperacilina/uso terapêutico , Tobramicina/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/efeitos adversos , Antibacterianos/uso terapêutico , Anti-Infecciosos/efeitos adversos , Anti-Infecciosos/uso terapêutico , Transplante de Medula Óssea/efeitos adversos , Ciprofloxacina/efeitos adversos , Método Duplo-Cego , Feminino , Febre/etiologia , Humanos , Leucemia/complicações , Linfoma/complicações , Masculino , Pessoa de Meia-Idade , Neutropenia/complicações , Neutropenia/etiologia , Infecções Oportunistas/tratamento farmacológico , Infecções Oportunistas/etiologia , Penicilinas/efeitos adversos , Penicilinas/uso terapêutico , Piperacilina/efeitos adversos , Tobramicina/efeitos adversos
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