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1.
BMC Cancer ; 22(1): 415, 2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35428207

RESUMO

BACKGROUND: Several bone-seeking radionuclides have been developed for palliation of metastatic bone pain since 1956, however, so far radium-223 dichloride is the first and only Food and Drug Administration (FDA) approved targeted alpha therapy for metastatic castration-resistant prostate cancer (mCRPC) based on ALSYMPCA phase 3 study. While radium-223 does improve pain and overall survival outcomes, the improvement can come at the expense of side effects such as bone marrow toxicity. The development of new and better treatment with long-standing pain relief is clearly an unmet medical need. METHODS: The study is a non-randomized phase II study. The study population consists of 25 patients with CRPC who had progressed on any lines of prior therapies and whose serum testosterone level is less than 50 ng/dl and have metastatic lesions to at least two bone sites, with at least one site that has clinically meaningful pain at baseline (≥ 4 on an 11-point intensity scale). Eligible patients will be given two cycles of Sn-117 m-DTPA every 8 weeks or 56 days. Treatment will be administered by slow IV injection over 5-10 min. Retreatment after two cycles is allowed if patients meet the following retreatment criteria. The primary objective is to evaluate the efficacy of Sn-117 m-DTPA on sustained pain response in patients with CRPC metastatic to at least two bone sites and at least one with clinically meaningful pain at baseline (≥ 4 on an 11-point pain intensity scale). Sustained pain response is defined as: 1) achieving pain index ≤ 3 within a 12-week period and 2) maintaining pain index ≤ 3 over a 16-week period. The secondary objectives are: safety and tolerability, measurement of Sn-117 m-DTPA activity by gamma-camera dosimetry scans, therapeutic efficacy, time to the first symptomatic skeletal event, duration of pain response, changes in PSA and ALP levels, patient-reported outcomes and progression free survival and overall survival. DISCUSSION: Sn-117 m-DTPA is a unique bone-targeting theranostic radiopharmaceutical agent that selectively binds most heavily to bone metastases sites. This study will be the first prospective phase II trial to assess the pain efficacy and anti-tumor activity of Sn-117 m-DTPA in mCRPC with at least one clinically meaningful pain at baseline. TRIAL REGISTRATION: ClincialTrials.gov Identifier: NCT04616547.


Assuntos
Neoplasias Ósseas , Dor do Câncer , Neoplasias de Próstata Resistentes à Castração , Rádio (Elemento) , Neoplasias Ósseas/secundário , Dor do Câncer/tratamento farmacológico , Dor do Câncer/etiologia , Humanos , Masculino , Ácido Pentético , Estudos Prospectivos , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Rádio (Elemento)/efeitos adversos
3.
Radiology ; 272(1): 79-90, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24620911

RESUMO

PURPOSE: To evaluate the effects of breast compression on breast cancer masses, contrast material enhancement of glandular tissue, and quality of magnetic resonance (MR) images in the identification and characterization of breast lesions. MATERIALS AND METHODS: This was a HIPAA-compliant, institutional review board-approved retrospective study, with waiver of informed consent. Images from 300 MR imaging examinations in 149 women (mean age ± standard deviation, 51.5 years ± 10.9; age range, 22-76 years) were evaluated. The women underwent diagnostic MR imaging (no compression) and MR-guided biopsy (with compression) between June 2008 and February 2013. Breast compression was expressed as a percentage relative to the noncompressed breast. Percentage enhancement difference was calculated between noncompressed- and compressed-breast images obtained in early and delayed contrast-enhanced phases. Breast density, lesion type (mass vs non-masslike enhancement [NMLE]), lesion size, percentage compression, and kinetic curve type were evaluated. Linear regression, receiver operating characteristic (ROC) curve analysis, and κ test were performed. RESULTS: Mean percentage compression was 31.3% ± 9.2 (range, 5.8%-53.2%). Percentage enhancement was higher in noncompressed- versus compressed-breast studies in early (146% ± 66 vs 107% ± 42, respectively; P < .001) and delayed (158% ± 68 vs 107% ± 42, respectively; P = .1) phases. Among breast lesions, 12% (seven of 59) were significantly smaller when compressed, which led to underestimation of TNM classification (P < .001). Breast masses (n = 35) showed significantly higher early percentage enhancement (157% ± 71) than lesions with NMLE (n = 15, 120% ± 40; P = .02) and a percentage enhancement difference (47.5% ± 64 vs 17% ± 28, respectively; P = .023). Kinetic curve performance for identifying invasive cancer decreased after compression (area under ROC curve = 0.53 vs 0.71, respectively; P = .02). Breast compression resulted in complete loss of enhancement of nine of 210 lesions (4%). CONCLUSION: Breast compression during biopsy affected breast lesion detection, lesion size, and dynamic contrast-enhanced MR imaging interpretation and performance. Limiting the application of breast compression is recommended, except when clinically necessary.


Assuntos
Neoplasias da Mama/diagnóstico , Imageamento por Ressonância Magnética/métodos , Adulto , Idoso , Biópsia , Neoplasias da Mama/patologia , Força Compressiva , Meios de Contraste , Feminino , Humanos , Meglumina/análogos & derivados , Pessoa de Meia-Idade , Compostos Organometálicos , Pressão , Estudos Retrospectivos
4.
J Comput Assist Tomogr ; 38(6): 941-8, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24983436

RESUMO

OBJECTIVE: This study optimizes use of 3-T magnetic resonance imaging (MRI) to delineate coronary venous anatomy and compares 3-T MRI with multidetector computed tomography (MDCT) measurements. METHODS: The study population included 37 consecutive subjects (22 men, 19-71 years old). Whole-heart contrast-enhanced MRI images at 3 T were acquired using segmented k-space gradient echo with inversion recovery prepared technique. The MDCT images were obtained using nonionic iodinated contrast. RESULTS: The coronary sinus and great cardiac, posterior interventricular, and anterior interventricular veins were visualized in 100% of cases by both MRI and MDCT. Detection of the posterior vein of the left ventricle and the left marginal vein by MRI was 97% and 81%, respectively. Bland-Altman plots showed agreement in ostial diameter measured by both modalities with correlation coefficients ranging from 0.5 to 0.76. Vein length and distances also agreed closely. CONCLUSIONS: Free-breathing whole-heart 3-dimensional MRI at 3 T provides high-spatial-resolution images and could offer an alternative imaging technique instead of MDCT scans.


Assuntos
Técnicas de Imagem Cardíaca , Vasos Coronários/anatomia & histologia , Vasos Coronários/diagnóstico por imagem , Imageamento Tridimensional , Imageamento por Ressonância Magnética , Tomografia Computadorizada Multidetectores , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Respiração , Adulto Jovem
5.
Health Phys ; 125(4): 316-319, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37548565

RESUMO

ABSTRACT: Many parenteral radiopharmaceuticals available as anticancer therapy are filtered by the kidneys and excreted in the urine. Here, physician leaders of radiation medicine, nuclear medicine/molecular imaging, and the radiotheranostics programs as well as radiation safety officers, collaborated to develop a decision-making guideline for the administration of therapeutic radiopharmaceuticals in patients with pretherapy or day-of-treatment incontinence. We discussed challenges and opportunities in the screening of patients in urine collection strategies according to grade of urinary incontinence and in subsequent coordination of care. Lutetium-177 ( 177 Lu)-based radiopharmaceutical therapies provided clinical examples of how our procedures were operationalized. Our key management issues of urinary incontinence were cutaneous radiation injury and redness, infection, or pain. In response, we developed clinical practice guidelines for the recognition and management of incontinence-related adverse events. Common adverse events of urinary incontinence were noted in this study. Our how-to guideline for the safe administration of therapeutic radiopharmaceuticals for patients with urinary incontinence warrants further investigation and should continue to be evaluated across all radiopharmaceutical therapy agents.


Assuntos
Medicina Nuclear , Incontinência Urinária , Humanos , Compostos Radiofarmacêuticos/efeitos adversos , Incontinência Urinária/etiologia , Incontinência Urinária/terapia , Incontinência Urinária/diagnóstico
6.
Brain Sci ; 13(2)2023 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-36831761

RESUMO

Co-occurrence of beta amyloid (Aß) and white matter hyperintensities (WMHs) increase the risk of dementia and both are considered biomarkers of preclinical dementia. Moderation and mediation modeling were used to define the interplay between global and regional Aß and WMHs measures in relation to executive function (EF) and memory composite scores outcomes at baseline and after approximately 2 years across a sample of 714 clinically normal participants from the Alzheimer's Disease Neuroimaging Initiative (ADNI 2). The moderation regression analysis showed additive effects of Aß and WMHs over baseline memory and EF scores (p = 0.401 and 0.061, respectively) and synergistic effects over follow-up EF (p < 0.05). Through mediation analysis, the data presented demonstrate that WMHs effects, mediated by global and regional amyloid burden, are responsible for baseline cognitive performance deficits in memory and EF. These findings suggest that Aß and WMHs contribute to baseline cognition independently while WMHs volumes exert effects on baseline cognitive performance directly and through influences on Aß accumulation.

7.
Brain Behav ; 13(10): e3209, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37534614

RESUMO

BACKGROUND AND PURPOSE: Cerebral small vessel disease (SVD) has been suggested to contribute to the pathogenesis of Alzheimer's disease (AD). Yet, the role of SVD in potentially contributing to AD pathology is unclear. The main objective of this study was to test the hypothesis that WMHs influence amyloid ß (Aß) levels within connected default mode network (DMN) tracts and cortical regions in cognitively unimpaired older adults. METHODS: Regional standard uptake value ratios (SUVr) from Aß-PET and white matter hyperintensity (WMH) volumes from three-dimensional magnetic resonance imaging FLAIR images were analyzed across a sample of 72 clinically unimpaired (mini-mental state examination ≥26), older adults (mean age 74.96 and standard deviation 8.13) from the Alzheimer's Disease Neuroimaging Initiative (ADNI3). The association of WMH volumes in major fiber tracts projecting from cortical DMN regions and Aß-PET SUVr in the connected cortical DMN regions was analyzed using linear regression models adjusted for age, sex, ApoE, and total brain volumes. RESULTS: The regression analyses demonstrate that increased WMH volumes in the superior longitudinal fasciculus were associated with increased regional SUVr in the inferior parietal lobule (p = .011). CONCLUSION: The findings suggest that the relation between Aß in parietal cortex is associated with SVD in downstream white matter (WM) pathways in preclinical AD. The biological relationships and interplay between Aß and WM microstructure alterations that precede overt WMH development across the continuum of AD progression warrant further study.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Substância Branca , Humanos , Idoso , Peptídeos beta-Amiloides/metabolismo , Doença de Alzheimer/patologia , Substância Branca/patologia , Rede de Modo Padrão/metabolismo , Rede de Modo Padrão/patologia , Encéfalo/patologia , Imageamento por Ressonância Magnética , Disfunção Cognitiva/patologia
8.
Med Phys ; 39(12): 7710-8, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23231318

RESUMO

PURPOSE: To evaluate the feasibility of using strain-encoded (SENC) breast magnetic resonance images (MRI) for breast cancer detection by examining the compression and relaxation response properties in phantoms and ex vivo breast samples. METHODS: A tissue phantom was constructed to mimic different sizes of breast masses and tissue stiffness. In addition, five human ex vivo whole breast specimens with and without masses were studied. MR data was acquired on a 3T scanner consisting of T(1)-weighted, fat suppressed spin echo T(2)-weighted, and SENC breast images. Mechanical tissue characteristics (strain) of the phantoms and breast tissue samples were measured using SENC imaging in both compression and relaxation modes. The breast tissue specimens were sectioned and stained in the same plane as the MRI for histological evaluation. RESULTS: For the phantom, SENC images showed soft masses with quantitative strain values between 35% and 50%, while harder masses had strain values between 0% and 20%. Combined compression (CMP) and relaxation (REX) breast SENC images separately categorized all masses into three different groups. For breast SENC, the signal intensities between ex vivo breast mass and breast glandular tissue were significantly different (-7.6 ± 2.6 verses -20.6 ± 5.4 for SENC-CMP, and 4.2 ± 1.5 verses 22.6 ± 5 for SENC-REX, p < 0.05). CONCLUSIONS: We have demonstrated that SENC breast MRI can be used to obtain mechanical tissue properties and give quantitative estimates of strain in tumors. This feasibility study provides the basis for future clinical studies.


Assuntos
Algoritmos , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/fisiopatologia , Técnicas de Imagem por Elasticidade/métodos , Interpretação de Imagem Assistida por Computador/métodos , Reconhecimento Automatizado de Padrão/métodos , Técnicas de Imagem por Elasticidade/instrumentação , Feminino , Humanos , Aumento da Imagem/métodos , Imagens de Fantasmas , Projetos Piloto , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
9.
Acad Radiol ; 29(1): 95-106, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34756348

RESUMO

RATIONALE AND OBJECTIVES: Standardized Uptake Value (SUV) is an important semiquantitative measurement used in the clinical and research domains to assess radiopharmaceutical concentration in tumors versus normal organs, but is susceptible to many factors beyond the tumor biological environment. So, the aim of this study is to identify the optimum internal reference among organs with physiological uptake in 68Ga-DOTATATE PET/CT (DOTA PET/CT) scans. MATERIALS AND METHODS: This HIPAA-compliant, IRB-approved study with waiver of consent included retrospective imaging review of 180 consecutive patients with neuroendocrine tumors presenting for DOTA PET/CT image acquisition: Ga-68 DOTATATE dose was reported as (0.054 mCi/Kg) scans between September 2018 and May 2019. Mean value of body weight normalized SUV (SUVbw) and lean body mass normalized SUV (SUL) of liver and spleen were measured. Information about the patients and scan characteristics were collected. The paired Grambsch test was used to compare variance among the measured SUVs. Spearman's rank correlation coefficient was used to assess correlation between SUVs and potential patient- and scan-specific confounding factors. RESULTS: Variance of SUL was significantly lower than variance of SUVbw in both liver and spleen (p-value < 0.0001). Variances of liver SUVbw and SUL were significantly lower than the corresponding spleen SUVs. Liver SUL showed the lowest variance (3.69% ± 1.25%) among all measured SUVs. CONCLUSION: SUL is a more reproducible, less variable, and therefore more reliable quantitative measure in DOTA PET/CT scans, compared SUVbw. Among the available organs with physiological uptake, liver SUL is the optimum internal reference given the liver's larger size and uniform SUL values resulting in lower variability and better reproducibility.


Assuntos
Compostos Organometálicos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Radioisótopos de Gálio , Humanos , Tomografia por Emissão de Pósitrons , Cintilografia , Compostos Radiofarmacêuticos , Reprodutibilidade dos Testes , Estudos Retrospectivos
10.
J Alzheimers Dis ; 88(3): 1127-1135, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35754276

RESUMO

BACKGROUND: Global amyloid-ß (Aß) deposition in the brain can be quantified by Aß-PET scans to support or refute a diagnosis of preclinical Alzheimer's disease (pAD). Yet, Aß-PET scans enable quantitative evaluation of regional Aß elevations in pAD, potentially allowing even earlier detection of pAD, long before global positivity is achieved. It remains unclear as to whether such regional changes are clinically meaningful. OBJECTIVE: Test the hypothesis that early focal regional amyloid deposition in the brain is associated with cognitive performance in specific cognitive domain scores in pAD. METHODS: Global and regional standardized uptake value ratios (SUVr) from 18F-florbetapir PET/CT scanning were determined using the Siemens Syngo.via® Neurology software package across a sample of 99 clinically normal participants with Montreal Cognitive Assessment (MoCA) scores≥23. Relationships between regional SUVr and cognitive test scores were analyzed using linear regression models adjusted for age, sex, and education. Participants were divided into two groups based on SUVr in the posterior cingulate and precuneus gyri (SUVR≥1.17). Between group differences in cognitive test scores were analyzed using ANCOVA models. RESULTS: Executive function performance was associated with increased regional SUVr in the precuneus and posterior cingulate regions only (p < 0.05). There were no significant associations between memory and Aß-PET SUVr in any regions of the brain. CONCLUSION: These data demonstrate that increased Aß deposition in the precuneus and posterior cingulate (the earliest brain regions affected with Aß pathology) is associated with changes in executive function that may precede memory decline in pAD.


Assuntos
Doença de Alzheimer , Amiloidose , Disfunção Cognitiva , Doença de Alzheimer/patologia , Amiloide/metabolismo , Peptídeos beta-Amiloides/metabolismo , Amiloidose/patologia , Compostos de Anilina , Encéfalo/patologia , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/patologia , Função Executiva , Giro do Cíngulo/metabolismo , Humanos , Lobo Parietal/patologia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Tomografia por Emissão de Pósitrons
11.
BMJ Neurol Open ; 4(2): e000301, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35949912

RESUMO

Objective: To evaluate the interim feasibility, safety and clinical measures data of direct delivery of regenerating peripheral nerve tissue (PNT) to the substantia nigra (SN) in participants with Parkinson's disease (PD). Methods: Eighteen (13 men/5 women) participants were unilaterally implanted with PNT to the SN, contralateral to the most affected side during the same surgery they were receiving deep brain stimulation (DBS) surgery. Autologous PNT was collected from the sural nerve. Participants were followed for safety and clinical outcomes for 2 years (including off-state Unified Parkinson's Disease Rating Scale (UPDRS) Part III assessments) with study visits every 6 months. Results: All 18 participants scheduled to receive PNT implantation received targeted delivery to the SN in addition to their DBS. All subjects were discharged the following day except for two: post-op day 2; post-op day 3. The most common study-related adverse events were hypoaesthesia and hyperaesthesias to the lateral aspect of the foot and ankle of the biopsied nerve (6 of 18 participants experienced). Clinical measures did not identify any hastening of PD measures providing evidence of safety and tolerability. Off-state UPDRS Part III mean difference scores were reduced at 12 months compared with baseline (difference=-8.1, 95% CI -2.4 to -13.9 points, p=0.005). No complications involving dyskinesias were observed. Conclusions: Targeting the SN for direct delivery of PNT was feasible with no serious adverse events related to the study intervention. Interim clinical outcomes show promising results meriting continued examination of this investigational approach. Trial registration number: NCT02369003.

12.
JCO Precis Oncol ; 6: e2100524, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-36103643

RESUMO

PURPOSE: Multidisciplinary molecular tumor boards (MTBs) interpret next-generation sequencing reports and help oncologists determine best therapeutic options; however, there is a paucity of data regarding their clinical utility. The purpose of this study was to determine if MTB-directed therapy improves progression-free survival (PFS) over immediately prior therapy in patients with advanced cancer. METHODS: This single-arm, prospective phase II clinical trial enrolled patients with advanced cancer with an actionable mutation who received MTB-recommended targeted therapy between January 1, 2017, and October 31, 2020. MTB-recommended both on-label (level 1 evidence) and off-label (evidence levels 2 and 3) therapies. Of the 93 enrolled patients, 43 were treated frontline and 50 received second-line or greater-line therapy. The primary outcome was the probability of patients treated with second-line or greater-line MTB-directed therapy who achieved a PFS ratio ≥ 1.3 (PFS on MTB-directed therapy divided by PFS on the patient's immediately prior therapy). Secondary outcomes included PFS for patients treated frontline and overall survival and adverse effects for the entire study population. RESULTS: The most common disease sites were lung (35 of 93, 38%), gynecologic (17 of 93, 18%), GI (16 of 93, 17%), and head and neck (7 of 93, 8%). The Kaplan-Meier estimate of the probability of PFS ratio ≥ 1.3 was 0.59 (95% CI, 0.47 to 0.75) for patients treated with second-line or greater-line MTB-directed therapy. The median PFS was 449 (range 42-1,125) days for patients treated frontline. The median overall survival was 768 (range 22-1,240) days. There were four nontreatment-related deaths. CONCLUSION: When treated with MTB-directed therapy, most patients experienced improved PFS compared with immediately prior treatment. MTB-directed targeted therapy may be a strategy to improve outcomes for patients with advanced cancer.


Assuntos
Neoplasias , Feminino , Humanos , Estimativa de Kaplan-Meier , Neoplasias/tratamento farmacológico , Intervalo Livre de Progressão , Estudos Prospectivos
13.
Med Phys ; 38(2): 743-53, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21452712

RESUMO

PURPOSE: In this study, the authors aim to develop a physical, tissue-mimicking phantom for quantitative evaluation of breast MRI protocols. The objective of this phantom is to address the need for improved standardization in breast MRI and provide a platform for evaluating the influence of image protocol parameters on lesion detection and discrimination. Quantitative comparisons between patient and phantom image properties are presented. METHODS: The phantom is constructed using a mixture of lard and egg whites, resulting in a random structure with separate adipose- and glandular-mimicking components. T1 and T2 relaxation times of the lard and egg components of the phantom were estimated at 1.5 T from inversion recovery and spin-echo scans, respectively, using maximum-likelihood methods. The image structure was examined quantitatively by calculating and comparing spatial covariance matrices of phantom and patient images. A static, enhancing lesion was introduced by creating a hollow mold with stereolithography and filling it with a gadolinium-doped water solution. RESULTS: Measured phantom relaxation values fall within 2 standard errors of human values from the literature and are reasonably stable over 9 months of testing. Comparison of the covariance matrices of phantom and patient data demonstrates that the phantom and patient data have similar image structure. Their covariance matrices are the same to within error bars in the anterior-posterior direction and to within about two error bars in the right-left direction. The signal from the phantom's adipose-mimicking material can be suppressed using active fat-suppression protocols. A static, enhancing lesion can also be included with the ability to change morphology and contrast agent concentration. CONCLUSIONS: The authors have constructed a phantom and demonstrated its ability to mimic human breast images in terms of key physical properties that are relevant to breast MRI. This phantom provides a platform for the optimization and standardization of breast MRI imaging protocols for lesion detection and characterization.


Assuntos
Mama , Imageamento por Ressonância Magnética/instrumentação , Imagens de Fantasmas , Tecido Adiposo/citologia , Tecido Adiposo/patologia , Mama/anatomia & histologia , Mama/citologia , Humanos
14.
AJR Am J Roentgenol ; 197(6): 1498-505, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22109308

RESUMO

OBJECTIVE: The purpose of this article is to evaluate the incremental value of pharmacokinetic analysis of dynamic contrast-enhanced (DCE) MRI compared with conventional breast MRI (morphology plus kinetic curve type analysis) in characterizing breast lesions as malignant or benign. SUBJECTS AND METHODS: Patients underwent 3D high-resolution T1-weighted contrast-enhanced MRI and DCE-MRI at 3 T and had pathology-proven diagnosis (95%) or more than 2 years of follow-up confirming lesion stability (5%). Lesions were identified using the high-spatial-resolution contrast-enhanced MRI. Morphologic features (margin, enhancement, and pattern) and conventional DCE-MRI results (kinetic curve types 1, 2, or 3) or pharmacokinetic parameters (forward volume transfer constant [K(trans)], reverse volume transfer constant [K(ep)], and the extravascular extracellular space volume per unit volume of tissue), were included in multivariate models for prediction of benign versus malignant diagnosis. RESULTS: Ninety-five patients with 101 lesions were included: 52% of patients were premenopausal and 48% were postmenopausal. Sixty-eight lesions (67.3%) were malignant and 33 (32.7%) were benign. There was a significant association between K(trans) and K(ep) and the diagnosis of benign versus malignant (p < 0.001). The area under the curve for morphologic features (lesion margin and enhancement pattern) was 0.85, whereas inclusion of K(trans) or K(ep) in the model showed similar modest improvement in performance (area under the curve, 0.88-0.89). For DCE-MRI, both pharmacokinetic modeling and kinetic curve type analysis improved characterization of malignant and benign breast lesions. A diagnostic model including lesion morphology plus either pharmacokinetic parameters or kinetic curve assessment showed similar diagnostic performance in characterizing breast lesions. CONCLUSION: The use of kinetic curve type assessment or pharmacokinetic modeling in conjunction with high-resolution 3D breast MRI appears to offer similar improvement in diagnostic performance. Although morphologic analysis alone provides good characterization of breast lesions on MRI as benign or malignant, analysis of the lesion perfusion on DCE-MRI using either kinetic curve shape assessment or a pharmacokinetic modeling approach improves diagnostic accuracy.


Assuntos
Neoplasias da Mama/diagnóstico , Meios de Contraste/farmacocinética , Imageamento por Ressonância Magnética/métodos , Meglumina/análogos & derivados , Compostos Organometálicos/farmacocinética , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Imageamento Tridimensional , Modelos Logísticos , Meglumina/farmacocinética , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Curva ROC , Técnica de Subtração
15.
Radiographics ; 31(3): 677-703, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21571651

RESUMO

Prostate cancer is the most frequently diagnosed cancer in males and the second leading cause of cancer-related death in men. Assessment of prostate cancer can be divided into detection, localization, and staging; accurate assessment is a prerequisite for optimal clinical management and therapy selection. Magnetic resonance (MR) imaging has been shown to be of particular help in localization and staging of prostate cancer. Traditional prostate MR imaging has been based on morphologic imaging with standard T1-weighted and T2-weighted sequences, which has limited accuracy. Recent advances include additional functional and physiologic MR imaging techniques (diffusion-weighted imaging, MR spectroscopy, and perfusion imaging), which allow extension of the obtainable information beyond anatomic assessment. Multiparametric MR imaging provides the highest accuracy in diagnosis and staging of prostate cancer. In addition, improvements in MR imaging hardware and software (3-T vs 1.5-T imaging) continue to improve spatial and temporal resolution and the signal-to-noise ratio of MR imaging examinations. Another recent advancement in the field is MR imaging guidance for targeted prostate biopsy, which is an alternative to the current standard of transrectal ultrasonography-guided systematic biopsy.


Assuntos
Imageamento por Ressonância Magnética/métodos , Neoplasias da Próstata/diagnóstico , Biomarcadores Tumorais/sangue , Biópsia/métodos , Progressão da Doença , Humanos , Imagem por Ressonância Magnética Intervencionista , Masculino , Estadiamento de Neoplasias , Prognóstico , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/patologia , Neoplasias da Próstata/terapia , Ultrassonografia de Intervenção
16.
Radiographics ; 31(6): 1773-91, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21997994

RESUMO

Diffusion-weighted imaging relies on the detection of the random microscopic motion of free water molecules known as Brownian movement. With the development of new magnetic resonance (MR) imaging technologies and stronger diffusion gradients, recent applications of diffusion-weighted imaging in whole-body imaging have attracted considerable attention, especially in the field of oncology. Diffusion-weighted imaging is being established as a pivotal aspect of MR imaging in the evaluation of specific organs, including the breast, liver, kidney, and those in the pelvis. When used in conjunction with apparent diffusion coefficient mapping, diffusion-weighted imaging provides information about the functional environment of water in tissues, thereby augmenting the morphologic information provided by conventional MR imaging. Detected changes include shifts of water from extracellular to intracellular spaces, restriction of cellular membrane permeability, increased cellular density, and disruption of cellular membrane depolarization. These findings are commonly associated with malignancies; therefore, diffusion-weighted imaging has many applications in oncologic imaging and can aid in tumor detection and characterization and in the prediction and assessment of response to therapy.


Assuntos
Imagem de Difusão por Ressonância Magnética/métodos , Neoplasias/diagnóstico , Artefatos , Meios de Contraste , Humanos , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador , Estadiamento de Neoplasias , Neoplasias/patologia , Neoplasias/terapia , Valor Preditivo dos Testes , Imagem Corporal Total
17.
Clin Imaging ; 75: 27-29, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33486149

RESUMO

Iatrogenic Cushing's syndrome has very well-known stigmata on physical examination but can pose a diagnostic challenge when it rarely presents radiologically. We present a classic albeit rarely encountered imaging appearance of Iatrogenic Cushing's on 18F-FDG-PET/CT, with diffuse subcutaneous white adipose proliferation and metabolic activation in a 7-year old patient one-month after starting a high dose steroid regimen for lymphoma. There was an extreme shift in the expected FDG biodistribution with dominant localization to the subcutaneous adipose tissue. This metabolic shift led to sub-threshold visceral biodistribution, rendering the scan non-diagnostic with regards to assessment of oncologic response. Aside from detailing the characteristic imaging findings of Iatrogenic Cushing's and its clinical importance, we discuss the physiologic basis of this imaging pattern and the rarer differential diagnosis to consider when this pattern of uptake is encountered on 18F-FDG-PET/CT.


Assuntos
Síndrome de Cushing , Fluordesoxiglucose F18 , Criança , Síndrome de Cushing/induzido quimicamente , Síndrome de Cushing/diagnóstico por imagem , Humanos , Doença Iatrogênica , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Distribuição Tecidual
18.
Front Oncol ; 11: 630827, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33747951

RESUMO

Radiopharmaceuticals are reemerging as attractive anticancer agents, but there are no universally adopted guidelines or standardized procedures for evaluating agent validity before early-phase trial implementation. To validate a radiopharmaceutical, it is desirous for the radiopharmaceutical to be specific, selective, and deliverable against tumors of a given, molecularly defined cancer for which it is intended to treat. In this article, we discuss four levels of evidence-target antigen immunohistochemistry, in vitro and in vivo preclinical experiments, animal biodistribution and dosimetry studies, and first-in-human microdose biodistribution studies-that might be used to justify oncology therapeutic radiopharmaceuticals in a drug-development sequence involving early-phase trials. We discuss common practices for validating radiopharmaceuticals for clinical use, everyday pitfalls, and commonplace operationalizing steps for radiopharmaceutical early-phase trials. We anticipate in the near-term that radiopharmaceutical trials will become a larger proportion of the National Cancer Institute Cancer Therapy Evaluation Program (CTEP) portfolio.

19.
Artigo em Inglês | MEDLINE | ID: mdl-34622117

RESUMO

With the introduction of precision medicine, treatment options for non-small-cell lung cancer have improved dramatically; however, underutilization, especially in disadvantaged patients, like those living in rural Appalachian regions, is associated with poorer survival. Molecular tumor boards (MTBs) represent a strategy to increase precision medicine use. UK HealthCare at the University of Kentucky (UK) implemented a statewide MTB in January 2017. We wanted to test the impact of UK MTB review on overall survival in Appalachian and other regions in Kentucky. METHODS: We performed a case-control study of Kentucky patients newly diagnosed with non-small-cell lung cancer between 2017 and 2019. Cases were reviewed by the UK MTB and were compared with controls without UK MTB review. Controls were identified from the Kentucky Cancer Registry and propensity-matched to cases. The primary end point was the association between MTB review and overall patient survival. RESULTS: Overall, 956 patients were included, with 343 (39%) residing in an Appalachian region. Seventy-seven (8.1%) were reviewed by the MTB and classified as cases. Cox regression analysis showed that poorer survival outcome was associated with lack of MTB review (hazard ratio [HR] = 8.61; 95% CI, 3.83 to 19.31; P < .0001) and living in an Appalachian region (hazard ratio = 1.43; 95% CI, 1.17 to 1.75; P = .004). Among individuals with MTB review, survival outcomes were similar regardless of whether they lived in Appalachia or other parts of Kentucky. CONCLUSION: MTB review is an independent positive predictor of overall survival regardless of residence location. MTBs may help overcome some health disparities for disadvantaged populations.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/mortalidade , Medicina de Precisão/métodos , Carcinoma Pulmonar de Células não Pequenas/epidemiologia , Carcinoma Pulmonar de Células não Pequenas/genética , Estudos de Casos e Controles , Feminino , Disparidades nos Níveis de Saúde , Humanos , Kentucky/epidemiologia , Masculino , Pessoa de Meia-Idade , Medicina de Precisão/tendências , Modelos de Riscos Proporcionais , Sistema de Registros/estatística & dados numéricos , População Rural/estatística & dados numéricos , Análise de Sobrevida
20.
JCI Insight ; 6(6)2021 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-33571166

RESUMO

BACKGROUNDBeige and brown adipose tissue (BAT) are associated with improved metabolic homeostasis. We recently reported that the ß3-adrenergic receptor agonist mirabegron induced beige adipose tissue in obese insulin-resistant subjects, and this was accompanied by improved glucose metabolism. Here we evaluated pioglitazone treatment with a combination pioglitazone and mirabegron treatment and compared these with previously published data evaluating mirabegron treatment alone. Both drugs were used at FDA-approved dosages.METHODSWe measured BAT by PET CT scans, measured beige adipose tissue by immunohistochemistry, and comprehensively characterized glucose and lipid homeostasis and insulin sensitivity by euglycemic clamp and oral glucose tolerance tests. Subcutaneous white adipose tissue, muscle fiber type composition and capillary density, lipotoxicity, and systemic inflammation were evaluated by immunohistochemistry, gene expression profiling, mass spectroscopy, and ELISAs.RESULTSTreatment with pioglitazone or the combination of pioglitazone and mirabegron increased beige adipose tissue protein marker expression and improved insulin sensitivity and glucose homeostasis, but neither treatment induced BAT in these obese subjects. When the magnitude of the responses to the treatments was evaluated, mirabegron was found to be the most effective at inducing beige adipose tissue. Although monotherapy with either mirabegron or pioglitazone induced adipose beiging, combination treatment resulted in less beiging than either alone. The 3 treatments also had different effects on muscle fiber type switching and capillary density.CONCLUSIONThe addition of pioglitazone to mirabegron treatment does not enhance beiging or increase BAT in obese insulin-resistant research participants.TRIAL REGISTRATIONClinicalTrials.gov NCT02919176.FUNDINGNIH DK112282 and P20GM103527 and Clinical and Translational Science Awards grant UL1TR001998.


Assuntos
Acetanilidas/farmacologia , Tecido Adiposo Bege/efeitos dos fármacos , Glucose/metabolismo , Hipoglicemiantes/farmacologia , Pioglitazona/farmacologia , Tiazóis/farmacologia , Acetanilidas/administração & dosagem , Sinergismo Farmacológico , Feminino , Teste de Tolerância a Glucose , Humanos , Hipoglicemiantes/administração & dosagem , Resistência à Insulina , Masculino , Pessoa de Meia-Idade , Obesidade/metabolismo , Pioglitazona/administração & dosagem , Tiazóis/administração & dosagem
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