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1.
Gynecol Oncol ; 163(3): 453-458, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34607711

RESUMO

OBJECTIVE: Uterine serous carcinoma (USC) is an aggressive subtype of endometrial cancer associated with worse survival outcomes in African American (AA) patients. This study evaluated tumor miRNA expression by race, clinical and tumor characteristics, and survival outcomes. METHODS: FFPE tumor tissue from hysterectomy specimens was identified for 29 AA cases. Case matching was performed by computer-based random assignment in a 1:1 ratio with Caucasian controls based on age, stage and histologic subtype (pure vs. mixed). RNA was extracted from 77 specimens (54 tumors and 23 matched normal endometrium). MicroRNA array profiling was performed by microRNA Hi-Power Labeling (Hy3/Hy5) and hybridization to miRCURY LNA microRNA Array 7th Gen. RESULTS: Clinical and treatment characteristics were similar for cases and controls, although use of adjuvant radiation was less common in African Americans (p = 0.03). Of 968 miRNAs analyzed, 649 were differentially expressed in normal endometrium vs. tumor. When compared by race, histologic subtype, stage or presence of LVI, no differentially expressed miRNAs were identified. In patients with disease recurrence at 3 years, the three most upregulated miRNAs were miR-1, miR-21-5p and miR-223. Of these, increased miR-223 expression (>median) was associated with worse OS (p = 0.0496) in an independent dataset (TCGA dataset) comprising of 140 patients with USC (mixed or pure serous). After adjusting for age, ethnicity and BMI, upregulation of miR-223 remained risk factor for death (adjusted HR 2.87, 95% CI 1.00-8.27). CONCLUSIONS: MiRNA profiling did not identify biological differences between AA and Caucasian patients with USC. Upregulation of miR-223 may be a prognostic factor in USC.


Assuntos
Negro ou Afro-Americano/genética , Cistadenocarcinoma Seroso/genética , MicroRNAs/genética , Neoplasias Uterinas/genética , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Estudos de Coortes , Cistadenocarcinoma Seroso/etnologia , Cistadenocarcinoma Seroso/patologia , Cistadenocarcinoma Seroso/terapia , Feminino , Perfilação da Expressão Gênica , Disparidades nos Níveis de Saúde , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Regulação para Cima , Neoplasias Uterinas/etnologia , Neoplasias Uterinas/patologia , Neoplasias Uterinas/terapia
2.
Brachytherapy ; 19(6): 725-731, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33183971

RESUMO

PURPOSE: Brachytherapy is critical for the curative treatment of locally advanced cervical cancer. Although brachytherapy use is declining in the United States (U.S.), novel interstitial or intracavitary applicators and advances in image guidance for applicator placement and treatment planning have allowed for tumor dose escalation while reducing normal tissue toxicity. Recent survey data have suggested insufficient brachytherapy training for radiation oncology trainees in the United States. This study aimed to address these gaps by developing and piloting a simulation-based education (SBE) workshop for MR-guided cervical cancer brachytherapy. METHODS AND MATERIALS: An SBE workshop was developed for graduate medical education (GME) trainees focusing on MR-guided brachytherapy for cervical cancer. Four hands-on stations, simulating aspects of the procedure, were led by a team of gynecological brachytherapy experts. The learners were radiation oncology residents and fellows in a U.S. GME training program. The primary outcome was feasibility, assessed by completion of the workshop within the time constraints of the curriculum. Learners completed preworkshop and postworkshop surveys to provide information on efficacy. RESULTS: The workshop was successfully completed in a 1-h block of GME didactic time. Ten trainees completed all four stations, and all completed preworkshop and postworkshop surveys, which showed improvements in knowledge and technical proficiency. Feedback was positive, and trainees requested additional learning opportunities. CONCLUSIONS: This study showed that GME-focused SBE in MR-guided cervical cancer brachytherapy was feasible. SBE provided a nonclinical environment in which to practice aspects of MR-guided brachytherapy. Ongoing work includes collaboration with other U.S. institutions. Future studies should focus on international adaptation.


Assuntos
Braquiterapia , Bolsas de Estudo/métodos , Internato e Residência/métodos , Radioterapia (Especialidade)/educação , Treinamento por Simulação , Neoplasias do Colo do Útero/radioterapia , Braquiterapia/métodos , Competência Clínica , Feminino , Humanos , Imageamento por Ressonância Magnética , Projetos Piloto , Dosagem Radioterapêutica , Inquéritos e Questionários , Neoplasias do Colo do Útero/diagnóstico por imagem , Neoplasias do Colo do Útero/patologia
3.
J Clin Oncol ; 34(9): 902-9, 2016 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-26351332

RESUMO

PURPOSE: The Clinical Evaluation of Pertuzumab and Trastuzumab (CLEOPATRA) study showed a 15.7-month survival benefit with the addition of pertuzumab to docetaxel and trastuzumab (THP) as first-line treatment for patients with human epidermal growth factor receptor 2 (HER2) -overexpressing metastatic breast cancer. We performed a cost-effectiveness analysis to assess the value of adding pertuzumab. PATIENT AND METHODS: We developed a decision-analytic Markov model to evaluate the cost effectiveness of docetaxel plus trastuzumab (TH) with or without pertuzumab in US patients with metastatic breast cancer. The model followed patients weekly over their remaining lifetimes. Health states included stable disease, progressing disease, hospice, and death. Transition probabilities were based on the CLEOPATRA study. Costs reflected the 2014 Medicare rates. Health state utilities were the same as those used in other recent cost-effectiveness studies of trastuzumab and pertuzumab. Outcomes included health benefits expressed as discounted quality-adjusted life-years (QALYs), costs in US dollars, and cost effectiveness expressed as an incremental cost-effectiveness ratio. One- and multiway deterministic and probabilistic sensitivity analyses explored the effects of specific assumptions. RESULTS: Modeled median survival was 39.4 months for TH and 56.9 months for THP. The addition of pertuzumab resulted in an additional 1.81 life-years gained, or 0.62 QALYs, at a cost of $472,668 per QALY gained. Deterministic sensitivity analysis showed that THP is unlikely to be cost effective even under the most favorable assumptions, and probabilistic sensitivity analysis predicted 0% chance of cost effectiveness at a willingness to pay of $100,000 per QALY gained. CONCLUSION: THP in patients with metastatic HER2-positive breast cancer is unlikely to be cost effective in the United States.


Assuntos
Anticorpos Monoclonais Humanizados/administração & dosagem , Anticorpos Monoclonais Humanizados/economia , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/economia , Neoplasias da Mama/tratamento farmacológico , Idoso , Neoplasias da Mama/economia , Neoplasias da Mama/enzimologia , Neoplasias da Mama/patologia , Análise Custo-Benefício , Técnicas de Apoio para a Decisão , Docetaxel , Feminino , Humanos , Cadeias de Markov , Pessoa de Meia-Idade , Modelos Econômicos , Invasividade Neoplásica , Receptor ErbB-2/biossíntese , Taxoides/administração & dosagem , Taxoides/economia , Trastuzumab/administração & dosagem , Trastuzumab/economia , Estados Unidos
4.
J Invest Surg ; 20(2): 121-33, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17454397

RESUMO

Magnetic resonance imaging (MRI) and magnetic resonance (MR) relaxometry were used to assess noninvasively the tissue response of a new uncoated hybrid braided suture made from a combination of ultra-high-molecular-weight polyethylene (UHMWPE) and polyester (polyethylene terephthalate) (PET) yarns in comparison to a silicone impregnated braided 100% polyester (PET) control suture (Ticron). Both biomaterials were monitored for a period of 30 days following implantation in both incised and nonincised paravertebral rabbit muscles. In all cases, MR images and relaxometry demonstrated that the hybrid suture elicited either a milder or a similar tissue and cellular response compared to the control suture. These findings were confirmed by conventional histological analysis of the surrounding tissues. They also demonstrated that the hybrid suture promoted faster healing in terms of collagen infiltration between the yarns and individual filaments. This milder inflammatory reaction and improved biocompatibility represent a real advantage in the healing performance of sutures for cardiac and vascular surgery, and support the need for continued research and development of hybrid structures. This study also demonstrated the ability of MRI techniques to noninvasively evaluate the biocompatibility of biomaterials. By extending the capacity of MR diagnostic tools from patients to experimental animals, it is now possible to validate the healing performance of foreign materials with statistical reliability and fewer animals.


Assuntos
Materiais Biocompatíveis/efeitos adversos , Teste de Materiais/métodos , Suturas/efeitos adversos , Animais , Lubrificantes , Imageamento por Ressonância Magnética , Músculo Esquelético , Coelhos , Âncoras de Sutura , Resultado do Tratamento , Cicatrização
5.
Clin Drug Investig ; 27(1): 67-74, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17177581

RESUMO

BACKGROUND AND OBJECTIVE: The choice of initial highly active antiretroviral therapy (HAART) should take into account the need to balance efficacy, adverse event risk, resistance concerns for the treatment of HIV and treatment costs. Increased risk of coronary heart disease (CHD) may be of special concern in the selection of HAART therapy, because differences in potential CHD risk have been reported for different regimens. This study aimed to estimate the long-term combined effects of HIV disease and antiretroviral (ARV)-related risk for CHD on quality-adjusted survival and healthcare costs for ARV-naive patients. METHODS: A previously validated Markov model was updated and supplemented with the Framingham CHD risk equation. In the model, the average patient was male, aged 37 years and had a baseline 10-year CHD risk of 4.6%. Patients started with either lopinavir/ritonavir or unboosted atazanavir as the first protease inhibitor (PI). Clinical trial data were used to estimate the differences between these two therapies. The daily PI costs were $US18.52 for lopinavir/ritonavir and $US22.08 for atazanavir. Other costs were estimated from Medicaid billing databases and average wholesale drug price reports. All model costs were reported as the 2004 present value in US currency. The model's time horizon reflected a patient's lifetime, and the perspective of the analysis was that of the healthcare system and did not include indirect costs in the model cost estimates. Various CHD risk levels were tested in the sensitivity analysis. RESULTS: In the base case, the model predicted a median duration of initial PI regimen of 5.6 years for lopinavir/ritonavir and 3.8 years for atazanavir. Over 10 years, patients who started on atazanavir had 30 additional AIDS events per 100 patients. Only 0.7 additional CHD events per 100 patients occurred for those who started on lopinavir/ritonavir. The model estimated 10-year total healthcare cost savings of $US12,543 per patient in the lopinavir/ritonavir group. The lifetime incremental cost effectiveness of lopinavir/ritonavir versus atazanavir was $US6797 per quality-adjusted life-year gained. CONCLUSION: Lopinavir/ritonavir is a highly cost-effective regimen relative to atazanavir for the treatment of HIV. The effect of lopinavir/ritonavir on long-term CHD risk was minimal compared with the increased risk of AIDS/death projected for a less efficacious first PI regimen. The cost of lipid-lowering drugs and treatment of CHD for patients taking the lopinavir/ritonavir regimen was only 1.2% of the cost of AIDS care per person, which was too small to have a significant effect on the overall cost savings with lopinavir/ritonavir therapy. Thus, a decision to forgo potency and durability in an ARV regimen for an ARV-naive patient in favour of a less potent regimen with an improved lipid profile may prove to be costly over time, in terms of both budget impact and life expectancy.


Assuntos
Doença das Coronárias/economia , Infecções por HIV/economia , Oligopeptídeos/economia , Piridinas/economia , Pirimidinonas/economia , Ritonavir/economia , Terapia Antirretroviral de Alta Atividade/efeitos adversos , Terapia Antirretroviral de Alta Atividade/economia , Terapia Antirretroviral de Alta Atividade/métodos , Sulfato de Atazanavir , Doença das Coronárias/induzido quimicamente , Doença das Coronárias/tratamento farmacológico , Análise Custo-Benefício , Honorários Farmacêuticos/estatística & dados numéricos , Infecções por HIV/tratamento farmacológico , Infecções por HIV/mortalidade , Inibidores da Protease de HIV/efeitos adversos , Inibidores da Protease de HIV/economia , Inibidores da Protease de HIV/uso terapêutico , HIV-1/efeitos dos fármacos , Custos de Cuidados de Saúde , Humanos , Lopinavir , Cadeias de Markov , Modelos Estatísticos , Oligopeptídeos/efeitos adversos , Oligopeptídeos/uso terapêutico , Piridinas/efeitos adversos , Piridinas/uso terapêutico , Pirimidinonas/efeitos adversos , Pirimidinonas/uso terapêutico , Anos de Vida Ajustados por Qualidade de Vida , Ritonavir/efeitos adversos , Ritonavir/uso terapêutico , Análise de Sobrevida , Taxa de Sobrevida , Fatores de Tempo
6.
Med Phys ; 34(12): 4876-89, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18196813

RESUMO

An automated method for evaluating the image quality of calcified plaques with respect to motion artifacts in noncontrast-enhanced cardiac computed tomography (CT) images is introduced. This method involves using linear regression (LR) and artificial neural network (ANN) regression models for predicting two patient-specific, region-of-interest-specific, reconstruction-specific and temporal phase-specific image quality indices. The first is a plaque motion index, which is derived from the actual trajectory of the calcified plaque and is represented on a continuous scale. The second is an assessability index, which reflects the degree to which a calcified plaque is affected by motion artifacts, and is represented on an ordinal five-point scale. Two sets of assessability indices were provided independently by two radiologists experienced in evaluating cardiac CT images. Inputs for the regression models were selected from 12 features characterizing the dynamic, morphological, and intensity-based properties of the calcified plaques. Whereas LR-velocity (LR-V) used only a single feature (three-dimensional velocity), the LR-multiple (LR-M) and ANN regression models used the same subset of these 12 features selected through stepwise regression. The regression models were parameterized and evaluated using a database of simulated calcified plaque images from the dynamic NCAT phantom involving nine heart rate/multi-sector gating combinations and 40 cardiac phases covering two cardiac cycles. Six calcified plaques were used for the plaque motion indices and three calcified plaques were used for both sets of assessability indices. In one configuration, images from the second cardiac cycle were used for feature selection and regression model parameterization, whereas images from the first cardiac cycle were used for testing. With this configuration, repeated measures concordance correlation coefficients (CCCs) and associated 95% confidence intervals for the LR-V, LR-M, and ANN were 0.817 [0.785, 0.848], 0.894 [0.869, 0.916], and 0.917 [0.892, 0.936] for the plaque motion indices. For the two sets of assess-ability indices, CCC values for the ANN model were 0.843 [0.791, 0.877] and 0.793 [0.747, 0.828]. These two CCC values were statistically greater than the CCC value of 0.689 [0.648, 0.727], which was obtained by comparing the two sets of assessability indices with each other. These preliminary results suggest that the variabilities of assessability indices provided by regression models can lie within the variabilities of the indices assigned by independent observers. Thus, the potential exists for using regression models and assessability indices for determining optimal phases for cardiac CT image interpretation.


Assuntos
Aterosclerose/diagnóstico por imagem , Calcinose/diagnóstico por imagem , Coração/diagnóstico por imagem , Movimento , Tomografia Computadorizada por Raios X , Aceleração , Artefatos , Humanos , Modelos Lineares , Miocárdio/metabolismo , Redes Neurais de Computação
7.
NMR Biomed ; 18(8): 587-94, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16273507

RESUMO

A Bayesian nonlinear hierarchical random coefficients model was used in a reanalysis of a previously published longitudinal study of the extracellular direct current (DC)-potential and apparent diffusion coefficient (ADC) responses to focal ischaemia. The main purpose was to examine the data for evidence of an ADC threshold for anoxic depolarisation. A Markov chain Monte Carlo simulation approach was adopted. The Metropolis algorithm was used to generate three parallel Markov chains and thus obtain a sampled posterior probability distribution for each of the DC-potential and ADC model parameters, together with a number of derived parameters. The latter were used in a subsequent threshold analysis. The analysis provided no evidence indicating a consistent and reproducible ADC threshold for anoxic depolarisation.


Assuntos
Hipóxia-Isquemia Encefálica/metabolismo , Cadeias de Markov , Algoritmos , Animais , Difusão , Método de Monte Carlo , Ratos
8.
J Cereb Blood Flow Metab ; 23(6): 677-88, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12796716

RESUMO

Markov chain Monte Carlo simulation was used in a reanalysis of the longitudinal data obtained by Harris et al. (J Cereb Blood Flow Metab 20:28-36) in a study of the direct current (DC) potential and apparent diffusion coefficient (ADC) responses to focal ischemia. The main purpose was to provide a formal analysis of the temporal relationship between the ADC and DC responses, to explore the possible involvement of a common latent (driving) process. A Bayesian nonlinear hierarchical random coefficients model was adopted. DC and ADC transition parameter posterior probability distributions were generated using three parallel Markov chains created using the Metropolis algorithm. Particular attention was paid to the within-subject differences between the DC and ADC time course characteristics. The results show that the DC response is biphasic, whereas the ADC exhibits monophasic behavior, and that the two DC components are each distinguishable from the ADC response in their time dependencies. The DC and ADC changes are not, therefore, driven by a common latent process. This work demonstrates a general analytical approach to the multivariate, longitudinal data-processing problem that commonly arises in stroke and other biomedical research.


Assuntos
Circulação Cerebrovascular/fisiologia , Ataque Isquêmico Transitório/fisiopatologia , Cadeias de Markov , Modelos Cardiovasculares , Animais , Simulação por Computador , Estudos Longitudinais , Ratos
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