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1.
J Natl Compr Canc Netw ; 22(4)2024 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-38688308

RESUMO

BACKGROUND: For elderly patients with high-grade gliomas, 3-week hypofractionated radiotherapy (HFRT) is noninferior to standard long-course radiotherapy (LCRT). We analyzed real-world utilization of HFRT with and without systemic therapy in Medicare beneficiaries treated with RT for primary central nervous system (CNS) tumors using Centers for Medicare & Medicaid Services data. METHODS: Radiation modality, year, age (65-74, 75-84, or ≥85 years), and site of care (freestanding vs hospital-affiliated) were evaluated. Utilization of HFRT (11-20 fractions) versus LCRT (21-30 or 31-40 fractions) and systemic therapy was evaluated by multivariable logistic regression. Medicare spending over the 90-day episode after RT planning initiation was analyzed using multivariable linear regression. RESULTS: From 2015 to 2019, a total of 10,702 RT courses (ie, episodes) were included (28% HFRT; 65% of patients aged 65-74 years). A considerable minority died within 90 days of RT planning initiation (n=1,251; 12%), and 765 (61%) of those received HFRT. HFRT utilization increased (24% in 2015 to 31% in 2019; odds ratio [OR], 1.2 per year; 95% CI, 1.1-1.2) and was associated with older age (≥85 vs 65-74 years; OR, 6.8; 95% CI, 5.5-8.4), death within 90 days of RT planning initiation (OR, 5.0; 95% CI, 4.4-5.8), hospital-affiliated sites (OR, 1.4; 95% CI, 1.3-1.6), conventional external-beam RT (vs intensity-modulated RT; OR, 2.7; 95% CI, 2.3-3.1), and no systemic therapy (OR, 1.2; 95% CI, 1.1-1.3; P<.001 for all). Increasing use of HFRT was concentrated in hospital-affiliated sites (P=.002 for interaction). Most patients (69%) received systemic therapy with no differences by site of care (P=.12). Systemic therapy utilization increased (67% in 2015 to 71% in 2019; OR, 1.1 per year; 95% CI, 1.0-1.1) and was less likely for older patients, patients who died within 90 days of RT planning initiation, those who received conventional external-beam RT, and those who received HFRT. HFRT significantly reduced spending compared with LCRT (adjusted ß for LCRT = +$8,649; 95% CI, $8,544-$8,755), whereas spending modestly increased with systemic therapy (adjusted ß for systemic therapy = +$270; 95% CI, $176-$365). CONCLUSIONS: Although most Medicare beneficiaries received LCRT for primary brain tumors, HFRT utilization increased in hospital-affiliated centers. Despite high-level evidence for elderly patients, discrepancy in HFRT implementation by site of care persists. Further investigation is needed to understand why patients with short survival may still receive LCRT, because this has major quality-of-life and Medicare spending implications.


Assuntos
Neoplasias do Sistema Nervoso Central , Medicare , Hipofracionamento da Dose de Radiação , Humanos , Idoso , Estados Unidos , Medicare/economia , Medicare/estatística & dados numéricos , Idoso de 80 Anos ou mais , Masculino , Feminino , Neoplasias do Sistema Nervoso Central/radioterapia , Neoplasias do Sistema Nervoso Central/economia , Neoplasias do Sistema Nervoso Central/mortalidade , Gastos em Saúde/estatística & dados numéricos
2.
Int J Radiat Oncol Biol Phys ; 116(3): 617-626, 2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-36586492

RESUMO

PURPOSE: The optimal management of early-stage, low-risk, hormone-positive breast cancer in older women remains controversial. Recent trials have shown that 5-fraction ultrahypofractionated whole-breast irradiation (U-WBI) has similar outcomes to longer courses, reducing the cost and inconvenience of treatment. We performed a cost-utility analysis to compare U-WBI to hormone therapy alone or their combination. METHODS AND MATERIALS: We simulated 3 different treatment approaches for women age 65 years or older with pT1-2N0 ER-positive invasive ductal carcinoma treated with lumpectomy with negative margins using a Markov microsimulation model. The strategies were U-WBI performed with a 3-dimensional conformal technique over 5 fractions without a boost ("radiation therapy [RT] alone"), adjuvant hormone therapy (anastrozole for 5 years) without RT ("aromatase-inhibitor [AI] alone"), or the combination of the 2. The combination strategy was calibrated to match trial results, and the relative effectiveness of the RT alone and AI alone strategies were inferred from previous randomized trials. The primary endpoint was the cost-effectiveness of the 3 strategies over a lifetime horizon as measured by the incremental cost-effectiveness ratio (ICER), with a value of $100,000/quality-adjusted life-year deemed "cost-effective." RESULTS: The model results compared with the prespecified target outcomes. On average, RT alone was the least expensive strategy ($14,775), with AI alone slightly more ($14,998), and combination therapy the costliest ($19,802). RT alone dominated AI alone (the incremental cost-effectiveness ratio [ICER] -$5089). Combination therapy, compared with RT alone, was slightly more expensive than our definition of cost-effective (ICER $113,468) but was cost-effective compared with AI alone (ICER $54,451). Probabilistic sensitivity analysis demonstrated RT alone to be cost-effective in 50% of trials, with combination therapy in 36% and AI alone in 14%. CONCLUSIONS: U-WBI alone appears the more cost-effective de-escalation strategy for these low-risk patients, compared with AI alone. Combining U-WBI and AI appears more costly but may be preferred by some patients.


Assuntos
Neoplasias da Mama , Feminino , Humanos , Idoso , Neoplasias da Mama/radioterapia , Neoplasias da Mama/patologia , Análise de Custo-Efetividade , Anastrozol , Mama/patologia , Inibidores da Aromatase , Análise Custo-Benefício , Hormônios
3.
Environ Sci Pollut Res Int ; 29(43): 65334-65352, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35488148

RESUMO

The issue of examining the stationarity of per capita energy consumption (PCEC) series is central in energy literature. Most of the existing studies examine this issue by employing unit root tests based on the time domain only providing a partial picture of the problem at hand due to not including the information related to the frequency domain. In contrast to existing studies, the present study uses a recently projected wavelet-based unit root testing scheme-Fourier wavelet KSS (FWKSS) introduced by Aydin and Pata. Energy 207:118245 (2020) which has several advantages over the existing wavelet unit root tests such as the ones proposed by Fan and Gençay (2010). Specifically, the FWKSS takes care of any possible smooth structural break in the data series under examination. This study re-examines the stationarity of PCEC across the globe covering for the first time a total of 133 countries and including all income groups constituting 49 high-, 76 middle- and 8 low-income countries. The selection of countries is made based on the availability of at least 25 years of annual time series data. The empirical results based on latest available data reveal that among 133 chosen countries, 67 countries are found to have non-stationary PCEC including 20 high-, 43 middle- and 4 low-income countries while the remaining 66 countries are found to have stationary PCEC including 29 high-, 33 middle- and 4 low-income countries. PCEC is found to be stationary in 79 of them including 35 high-, 40 middle- and 4 low-income countries. Some relevant policy implications are discussed as well.


Assuntos
Dióxido de Carbono , Desenvolvimento Econômico , Produto Interno Bruto , Renda
4.
Spine (Phila Pa 1976) ; 47(5): E187-E195, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-34224512

RESUMO

STUDY DESIGN: Retrospective, randomized, radiographic study assessing age-related changes (ARCs) on lumbar magnetic resonance imaging (MRI) using an ensemble method. OBJECTIVES: This study proposed to develop a novel reporting method to calculate a predicted "age estimate" for the ARC seen on lumbar MRI. SUMMARY OF BACKGROUND DATA: Lumbar MRI reports include pathological findings but usually not the prevalence data of common findings which has been shown to decrease the need for narcotics in the management of non-specific lower back pain (NSLBP). Comparing the normal age estimation for lumbar spine degenerative changes/ARC on MRI and comparing this to the patient's real age may improve patient outcome in the management of NSLBP. METHODS: A total of 60 lumbar MRI were taken from patients aged between 0 and 100 years. Lumbar MRI features reported as associated with age on review of the literature were measured on each MRI and statistically evaluated for correlation with age. Factors found to be associated were then entered into an ensemble model consisting of several machine learning techniques. The resulting ensemble model was then tested to predict age for a further 10 random lumbar MRI scans. One further lumbar MRI was then assessed for observer variability. RESULTS: Features that correlated with age were disc signal intensity, the appearance of paravertebral and psoas muscle, disc height, facet joint size, ligamentum flavum thickness, Schmorl nodes, Modic changes, vertebral osteophytes, and high-intensity zones. With the ensemble model, 80% of estimated spinal age were within 11 years of the subjects' physical age. CONCLUSION: It would appear that the intervertebral discs, and many other structures that are subjected to loading in and around the lumbar spine change their lumbar MRI appearance in a predictable way with increasing age. ARC on lumbar MRI can be assessed to predict an "expected age" for the subject.Level of Evidence: 2.


Assuntos
Degeneração do Disco Intervertebral , Região Lombossacral , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento , Criança , Pré-Escolar , Humanos , Lactente , Recém-Nascido , Degeneração do Disco Intervertebral/diagnóstico por imagem , Vértebras Lombares/diagnóstico por imagem , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
5.
JCO Oncol Pract ; 17(8): e1055-e1074, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33970684

RESUMO

PURPOSE: Adjuvant therapy in patients with ductal carcinoma in situ who undergo partial mastectomy remains controversial, particularly for low-risk patients (60 years or older, estrogen-positive, tumor extent < 2.5 cm, grade 1 or 2, and margins ≥ 3 mm). We performed a cost-effectiveness analysis comparing three strategies: no adjuvant treatment after surgery, a five-fraction course of accelerated partial breast irradiation using intensity-modulated radiation therapy (accelerated partial breast irradiation [APBI]-alone), or APBI plus an aromatase inhibitor for 5 years. MATERIALS AND METHODS: Outcomes including local recurrence, distant metastases, and survival as well as toxicity data were modeled by a patient-level Markov microsimulation model, which were validated against trial data. Costs of treatment and possible adverse events were included from the societal perspective over a lifetime horizon, adjusted to 2019 US dollars and extracted from Medicare reimbursement data. Quality-adjusted life-years (QALYs) were calculated based on utilities extracted from the literature. RESULTS: No adjuvant therapy was the least costly approach ($5,744), followed by APBI-alone ($11,070); combined therapy was costliest ($16,052). Adjuvant therapy resulted in slightly higher QALYs (no adjuvant, 11.320; APBI-alone, 11.343; and combination, 11.381). In the base case, no treatment was the cost-effective strategy, with an incremental cost-effectiveness ratio of $239,109/QALY for APBI-alone and $171,718/QALY for combined therapy. The incremental cost-effectiveness ratio for combined therapy compared with APBI-alone was $131,949. Probabilistic sensitivity analyses found that no therapy was cost effective (defined as $100,000/QALY of lower) in 63% of trials, APBI-alone in 19%, and the combination in 18%. CONCLUSION: No adjuvant therapy represents the most cost-effective approach for postmenopausal women 60 years or older who receive partial mastectomy for low-risk ductal carcinoma in situ.


Assuntos
Neoplasias da Mama , Carcinoma Intraductal não Infiltrante , Idoso , Neoplasias da Mama/radioterapia , Carcinoma Intraductal não Infiltrante/radioterapia , Análise Custo-Benefício , Feminino , Humanos , Mastectomia , Medicare , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Estados Unidos
6.
J Healthc Eng ; 2020: 8824907, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33354309

RESUMO

There is a need to develop an effective data preservation scheme with minimal information loss when the patient's data are shared in public interest for different research activities. Prior studies have devised different approaches for data preservation in healthcare domains; however, there is still room for improvement in the design of an elegant data preservation approach. With that motivation behind, this study has proposed a medical healthcare-IoTs-based infrastructure with restricted access. The infrastructure comprises two algorithms. The first algorithm protects the sensitivity information of a patient with quantifying minimum information loss during the anonymization process. The algorithm has also designed the access polices comprising the public access, doctor access, and the nurse access, to access the sensitivity information of a patient based on the clustering concept. The second suggested algorithm is K-anonymity privacy preservation based on local coding, which is based on cell suppression. This algorithm utilizes a mapping method to classify the data into different regions in such a manner that the data of the same group are placed in the same region. The benefit of using local coding is to restrict third-party users, such as doctors and nurses, when trying to insert incorrect values in order to access real patient data. Efficiency of the proposed algorithm is evaluated against the state-of-the-art algorithm by performing extensive simulations. Simulation results demonstrate benefits of the proposed algorithms in terms of efficient cluster formation in minimum time, minimum information loss, and execution time for data dissemination.


Assuntos
Confidencialidade , Privacidade , Algoritmos , Análise por Conglomerados , Atenção à Saúde , Humanos
7.
Breast Cancer Res Treat ; 182(2): 355-365, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32468336

RESUMO

PURPOSE: We performed a cost-effectiveness analysis of three strategies for the adjuvant treatment of early breast cancer in women age 70 years or older: an aromatase inhibitor (AI-alone) for 5 years, a 5-fraction course of accelerated partial-breast irradiation using intensity-modulated radiation therapy (APBI-alone), or their combination. METHODS: We constructed a patient-level Markov microsimulation from the societal perspective. Effectiveness data (local recurrence, distant metastases, survival), and toxicity data were obtained from randomized trials when possible. Costs of side effects were included. Costs were adjusted to 2019 US dollars and extracted from Medicare reimbursement data. Quality-adjusted life-years (QALY) were calculated using utilities extracted from the literature. RESULTS: The strategy of AI-alone ($12,637) was cheaper than both APBI-alone ($13,799) and combination therapy ($18,012) in the base case. All approaches resulted in similar QALY outcomes (AI-alone 7.775; APBI-alone 7.768; combination 7.807). In the base case, AI-alone was the cost-effective strategy and dominated APBI-alone, while combined therapy was not cost-effective when compared to AI-alone ($171,451/QALY) or APBI-alone ($107,932/QALY). In probabilistic sensitivity analyses, AI-alone was cost-effective at $100,000/QALY in 50% of trials, APBI-alone in 28% and the combination in 22%. Scenario analysis demonstrated that APBI-alone was more effective than AI-alone when AI compliance was lower than 26% at 5 years. CONCLUSIONS: Based on a Markov microsimulation analysis, both AI-alone and APBI-alone are appropriate options for patients 70 years or older with early breast cancer with small cost differences noted. A prospective trial comparing the approaches is warranted.


Assuntos
Inibidores da Aromatase/economia , Neoplasias da Mama/terapia , Análise Custo-Benefício/métodos , Recidiva Local de Neoplasia/epidemiologia , Radioterapia de Intensidade Modulada/economia , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Inibidores da Aromatase/administração & dosagem , Inibidores da Aromatase/efeitos adversos , Neoplasias da Mama/economia , Neoplasias da Mama/mortalidade , Quimiorradioterapia Adjuvante/efeitos adversos , Quimiorradioterapia Adjuvante/economia , Quimiorradioterapia Adjuvante/métodos , Fracionamento da Dose de Radiação , Feminino , Humanos , Cadeias de Markov , Medicare/economia , Medicare/estatística & dados numéricos , Modelos Econômicos , Recidiva Local de Neoplasia/prevenção & controle , Cooperação do Paciente/estatística & dados numéricos , Estudos Prospectivos , Anos de Vida Ajustados por Qualidade de Vida , Radioterapia de Intensidade Modulada/efeitos adversos , Ensaios Clínicos Controlados Aleatórios como Assunto , Estados Unidos/epidemiologia
8.
J Healthc Eng ; 2020: 6680002, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33489060

RESUMO

In the recent era, a liver syndrome that causes any damage in life capacity is exceptionally normal everywhere throughout the world. It has been found that liver disease is exposed more in young people as a comparison with other aged people. At the point when liver capacity ends up, life endures just up to 1 or 2 days scarcely, and it is very hard to predict such illness in the early stage. Researchers are trying to project a model for early prediction of liver disease utilizing various machine learning approaches. However, this study compares ten classifiers including A1DE, NB, MLP, SVM, KNN, CHIRP, CDT, Forest-PA, J48, and RF to find the optimal solution for early and accurate prediction of liver disease. The datasets utilized in this study are taken from the UCI ML repository and the GitHub repository. The outcomes are assessed via RMSE, RRSE, recall, specificity, precision, G-measure, F-measure, MCC, and accuracy. The exploratory outcomes show a better consequence of RF utilizing the UCI dataset. Assessing RF using RMSE and RRSE, the outcomes are 0.4328 and 87.6766, while the accuracy of RF is 72.1739% that is also better than other employed classifiers. However, utilizing the GitHub dataset, SVM beats other employed techniques in terms of increasing accuracy up to 71.3551%. Moreover, the comprehensive outcomes of this exploration can be utilized as a reference point for further research studies that slight assertion concerning the enhancement in extrapolation through any new technique, model, or framework can be benchmarked and confirmed.


Assuntos
Algoritmos , Aprendizado de Máquina , Adolescente , Idoso , Humanos , Fígado
9.
Int J Radiat Oncol Biol Phys ; 105(2): 296-306, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31212043

RESUMO

PURPOSE: Hormone therapy without radiation therapy is considered appropriate for women age 70 or above with low-risk, hormone-positive breast cancer after partial mastectomy. However, some patients may prefer radiation without hormone therapy, for which there is minimal modern data. We modeled the comparative efficacy of aromatase inhibition alone without radiation versus radiation alone without hormone therapy. METHODS AND MATERIALS: We constructed a patient-level Markov model and compared 5 years of anastrozole to a 15-fraction course of radiation without boost or anastrozole. The relative effectiveness between treatments was based on the National Surgical Adjuvant Breast and Bowel Project B-21 trial, which was further adjusted such that the endocrine-alone arm matched the Cancer and Leukemia Group B 9343 and PRIME II trials. Common or severe side effects were considered. Eight survival metrics were assessed and validated against clinical trial data. The cost-efficacy of each strategy was considered using the quality-adjusted life year and incremental cost-effectiveness ratio (ICER). RESULTS: The model's predicted outcomes matched those demonstrated by modern trials. Aromatase inhibitors were superior in preventing contralateral cancers, with a small impact on the risk of distant metastatic disease. Radiation was superior in preventing ipsilateral breast tumor recurrence with a small impact on regional failure. No clinically significant differences were seen in the other 4 oncologic endpoints. Differences in quality-adjusted life years were small, but radiation therapy was $3809 more expensive over the average lifetime. The ICER suggested anastrozole was cost-effective in 62% of probabilistic simulations. However, the ICER was unstable owing to a denominator that approached zero. CONCLUSIONS: Women age 70 or above with low-risk early breast cancer who are reluctant or unable to pursue adjuvant aromatase inhibition can safely pursue adjuvant radiation alone with limited differences in outcome and a modest increase in costs.


Assuntos
Anastrozol/uso terapêutico , Antineoplásicos Hormonais/uso terapêutico , Inibidores da Aromatase/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/radioterapia , Cadeias de Markov , Idoso , Idoso de 80 Anos ou mais , Anastrozol/economia , Antineoplásicos Hormonais/economia , Inibidores da Aromatase/economia , Neoplasias da Mama/química , Neoplasias da Mama/prevenção & controle , Ensaios Clínicos como Assunto , Análise Custo-Benefício , Fracionamento da Dose de Radiação , Feminino , Humanos , Mastectomia Segmentar , Metanálise como Assunto , Recidiva Local de Neoplasia/prevenção & controle , Probabilidade , Estudos Prospectivos , Anos de Vida Ajustados por Qualidade de Vida , Radioterapia/economia , Radioterapia Adjuvante , Receptores de Estrogênio , Eficiência Biológica Relativa , Risco , Terapia de Salvação/métodos
10.
Int J Radiat Oncol Biol Phys ; 104(4): 714-723, 2019 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-30557673

RESUMO

PURPOSE: Prior authorization (PA) has been widely implemented for proton beam therapy (PBT). We sought to determine the association between PA determination and patient characteristics, practice guidelines, and potential treatment delays. METHODS AND MATERIALS: A single-institution retrospective analysis was performed of all patients considered for PBT between 2015 and 2018 at a National Cancer Institute-designated Comprehensive Cancer Center. Differences in treatment start times and denial rates over time were compared, and multivariable logistic regression was used to identify predictors of initial denial. RESULTS: A total of 444 patients were considered for PBT, including 396 adult and 48 pediatric patients. The American Society for Radiation Oncology model policy supported PBT coverage for 77% of the cohort. Of adult patients requiring PA, 64% were initially denied and 32% remained denied after appeal. In patients considered for reirradiation or randomized phase 3 trial enrollment, initial denial rates were 57% and 64%, respectively. Insurance coverage was not related to diagnosis, reirradiation, trial enrollment, or the American Society for Radiation Oncology model policy guidelines, but it was related to insurance category on multivariable analysis (P < .001). Over a 3-year timespan, initial denial rates increased from 55% to 74% (P = .034). PA delayed treatment start by an average of 3 weeks (and up to 4 months) for those requiring appeal (P < .001) and resulted in 19% of denied patients abandoning radiation treatment altogether. Of pediatric patients, 9% were initially denied, all of whom were approved after appeal, and PA requirement did not delay treatment start (P = .47). CONCLUSIONS: PA requirements in adults represent a significant burden in initiating PBT and cause significant delays in patient care. Insurance approval is arbitrary and has become more restrictive over time, discordant with national clinical practice guidelines. Payors and providers should seek to streamline coverage policies in alignment with established guidelines to ensure appropriate and timely patient care.


Assuntos
Cobertura do Seguro/estatística & dados numéricos , Reembolso de Seguro de Saúde/estatística & dados numéricos , Neoplasias/radioterapia , Autorização Prévia/estatística & dados numéricos , Terapia com Prótons/economia , Tempo para o Tratamento/estatística & dados numéricos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Feminino , Humanos , Revisão da Utilização de Seguros/estatística & dados numéricos , Masculino , Medicare/estatística & dados numéricos , Pessoa de Meia-Idade , Terapia com Prótons/estatística & dados numéricos , Análise de Regressão , Estudos Retrospectivos , Estados Unidos , Adulto Jovem
11.
Asian Cardiovasc Thorac Ann ; 26(4): 273-276, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29587523

RESUMO

Background Left atrial enlargement is considered to be a robust, strong, and widely acceptable indicator of cardiovascular outcomes. Echocardiography is the gold standard for measurement of left atrial size, but electrocardiography can be simple, cost-effective, and noninvasive in clinical practice. This study was undertaken to assess the diagnostic accuracy of an established electrocardiographic criterion for left atrial enlargement, taking 2-dimensional echocardiography as the gold-standard technique. Methods A cross-sectional study was conducted on 146 consecutively selected patients with the complaints of dyspnea and palpitation and with a murmur detected on clinical examination, from September 10, 2016 to February 10, 2017. Electrocardiography and echocardiography were performed in all patients. Patients with a negative P wave terminal force in lead V1 > 40 ms·mm on electrocardiography or left atrial dimension > 40 mm on echocardiography were classified as having left atrial enlargement. Sensitivity and specificity were calculated to assess the diagnostic accuracy. Results Taking 2-dimensional echocardiography as the gold-standard technique, electrocardiography correctly diagnosed 68 patients as positive for left atrial enlargement and 12 as negative. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of electrocardiography for left atrial enlargement were 54.4%, 57.1%, 88.3%, 17.4%, and 54.8%, respectively. Conclusion The electrocardiogram appears to be a reasonable indicator of left atrial enlargement. In case of nonavailability of echocardiography, electrocardiography can be used for diagnosis of left atrial enlargement.


Assuntos
Função do Átrio Esquerdo , Remodelamento Atrial , Cardiomegalia/diagnóstico , Eletrocardiografia , Átrios do Coração/fisiopatologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Cardiomegalia/diagnóstico por imagem , Cardiomegalia/fisiopatologia , Estudos Transversais , Ecocardiografia , Feminino , Átrios do Coração/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Adulto Jovem
12.
Int J Radiat Oncol Biol Phys ; 97(2): 287-295, 2017 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-27986343

RESUMO

PURPOSE: Hypofractionated whole breast irradiation and accelerated partial breast irradiation (APBI) offer women options for shorter courses of breast radiation therapy. The impact of these shorter schedules on the breast cancer populations of emerging economies with limited radiation therapy resources is unknown. We hypothesized that adoption of these schedules would improve throughput in the system and, by allowing more women access to life-saving treatments, improve patient survival within the system. METHODS AND MATERIALS: We designed a Markov chain model to simulate the different health states that a postlumpectomy or postmastectomy patient could enter over the course of a 20-year follow-up period. Transition rates between health states were adapted from published data on recurrence rates. We used primary data from a tertiary care hospital in Lahore, Pakistan, to populate the model with proportional use of mastectomy versus breast conservation and to estimate the proportion of patients suitable for APBI. Sensitivity analyses on the use of APBI and relative efficacy of APBI were conducted to study the impact on the population. RESULTS: The shorter schedule resulted in more women alive and more women remaining without evidence of disease (NED) compared with the conventional schedule, with an absolute difference of about 4% and 7% at 15 years, respectively. Among women who had lumpectomies, the chance of remaining alive and with an intact breast was 62% in the hypofractionation model and 54% in the conventional fractionation model. CONCLUSIONS: Increasing throughput in the system can result in improved survival, improved chances of remaining without evidence of disease, and improved chances of remaining alive with a breast. These findings are significant and suggest that adoption of hypofractionation in emerging economies is not simply a question of efficiency and cost but one of access to care and patient survivorship.


Assuntos
Neoplasias da Mama/mortalidade , Neoplasias da Mama/radioterapia , Países em Desenvolvimento , Cadeias de Markov , Hipofracionamento da Dose de Radiação , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/cirurgia , Institutos de Câncer/estatística & dados numéricos , Feminino , Seguimentos , Humanos , Mastectomia/mortalidade , Mastectomia/estatística & dados numéricos , Mastectomia Segmentar/mortalidade , Mastectomia Segmentar/estatística & dados numéricos , Pessoa de Meia-Idade , Paquistão/epidemiologia , Período Pós-Operatório , Radioterapia/métodos , Radioterapia/estatística & dados numéricos , Taxa de Sobrevida , Fatores de Tempo , Falha de Tratamento
13.
J Appl Clin Med Phys ; 17(5): 90-98, 2016 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-27685117

RESUMO

This work investigated the possibility of using proton beam for total body irradia-tion (TBI). We hypothesized the broad-slow-rising entrance dose from a monoen-ergetic proton beam can deliver a uniform dose to patient with varied thickness. Comparing to photon-based TBI, it would not require any patient-specific com-pensator or beam spoiler. The hypothesis was first tested by simulating 250 MeV, 275 MeV, and 300 MeV protons irradiating a wedge-shaped water phantom in a paired opposing arrangement using Monte Carlo (MC) method. To allow ± 7.5% dose variation, the maximum water equivalent thickness (WET) of a treatable patient separation was 29 cm for 250 MeV proton, and > 40 cm for 275 MeV and 300 MeV proton. The compared 6 MV photon can only treat patients with up to 15.5 cm water-equivalent separation. In the second step, we simulated the dose deposition from the same beams on a patient's whole-body CT scan. The maximum patient separation in WET was 23 cm. The calculated whole-body dose variations were ± 8.9%, ± 9.0%, ± 9.6%, and ± 14% for 250 MeV proton, 275 MeV proton, 300 MeV proton, and 6 MV photon. At last, we tested the current machine capability to deliver a monoenergetic proton beam with a large uniform field. Experiments were performed on a compact double scattering single-gantry proton system. With its C-shaped gantry design, the source-to-surface distance (SSD) reached 7 m. The measured dose deposition curve had 22 cm relatively flat entrance region. The full width half maximum field size was measured 105 cm. The current scatter filter had to be redesigned to produce a uniform intensity at such treatment distance. In con-clusion, this work demonstrated the possibility of using proton beam for TBI. The current commercially available proton machines would soon be ready for such task.


Assuntos
Neoplasias/radioterapia , Imagens de Fantasmas , Terapia com Prótons , Irradiação Corporal Total/métodos , Humanos , Método de Monte Carlo , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada/métodos , Irradiação Corporal Total/instrumentação
14.
Int J Radiat Oncol Biol Phys ; 95(1): 505-516, 2016 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-27084663

RESUMO

Radiation dose escalation has been shown to improve local control and survival in patients with non-small cell lung cancer in some studies, but randomized data have not supported this premise, possibly owing to adverse effects. Because of the physical characteristics of the Bragg peak, proton therapy (PT) delivers minimal exit dose distal to the target volume, resulting in better sparing of normal tissues in comparison to photon-based radiation therapy. This is particularly important for lung cancer given the proximity of the lung, heart, esophagus, major airways, large blood vessels, and spinal cord. However, PT is associated with more uncertainty because of the finite range of the proton beam and motion for thoracic cancers. PT is more costly than traditional photon therapy but may reduce side effects and toxicity-related hospitalization, which has its own associated cost. The cost of PT is decreasing over time because of reduced prices for the building, machine, maintenance, and overhead, as well as newer, shorter treatment programs. PT is improving rapidly as more research is performed particularly with the implementation of 4-dimensional computed tomography-based motion management and intensity modulated PT. Given these controversies, there is much debate in the oncology community about which patients with lung cancer benefit significantly from PT. The Particle Therapy Co-operative Group (PTCOG) Thoracic Subcommittee task group intends to address the issues of PT indications, advantages and limitations, cost-effectiveness, technology improvement, clinical trials, and future research directions. This consensus report can be used to guide clinical practice and indications for PT, insurance approval, and clinical or translational research directions.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/radioterapia , Consenso , Neoplasias Pulmonares/radioterapia , Terapia com Prótons/métodos , Carcinoma Pulmonar de Células não Pequenas/patologia , Ensaios Clínicos como Assunto , Humanos , Neoplasias Pulmonares/patologia , Movimento , Tratamentos com Preservação do Órgão , Órgãos em Risco/efeitos da radiação , Terapia com Prótons/economia , Lesões por Radiação/prevenção & controle , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada/métodos , Espalhamento de Radiação , Carga Tumoral
15.
Clin Imaging ; 38(3): 259-64, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24559751

RESUMO

OBJECTIVE: To develop a simplified method to quantify liver fat using computed tomography (CT) fat % index (CTFPI) compared to liver spleen method (CTL/S, CTL-S). METHODS: Noncontrast CT of the liver was performed in 89 patients (overweight, obese, severely obese) to quantify fat, using the following: CTFPI=[(65-patient HU)/65]×100, normal live r=65 HU. RESULTS: There was a strong linear correlation between CTFPI and the standard method of assessing liver fat using CTL/S (r=-0.901), CTL-S (r=-0.911). Hepatic HU and CTFPI were significantly different in the severely obese group compared to other two groups (P<.05). CONCLUSION: Significant correlation indicates equal diagnostic accuracy of the two methods in appropriately calibrated scanners.


Assuntos
Gorduras/análise , Fígado Gorduroso/diagnóstico por imagem , Fígado/diagnóstico por imagem , Obesidade/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
16.
Urol Ann ; 5(1): 18-22, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23662003

RESUMO

INTRODUCTION: There is a paucity of a standardized post-operative complications grading system in urology especially in the elderly population. Studies show satisfactory survival and oncological outcomes albeit with a slight increase in post-operative morbidity compared to younger patients. The Clavien-Dindo classification for post-operative complications is established as a valid system worldwide and applicable in many fields of surgery. PURPOSE: Retrospective assessment of post-operative complications in patients >75 years who underwent open/laparoscopic nephrectomy/nephroureterectomy for renal diseases and grading the post-operative complications according to the Clavien-Dindo classification. MATERIALS AND METHODS: Retrospective review of case notes was performed in patients >75 years who underwent a laparoscopic/open nephrectomy/nephroureterectomy between 2000 and 2008. Post-operative complications were graded according to the Clavien-Dindo classification. RESULTS: A total of 54 patients >75 years underwent nephrectomy/nephroureterectomy. 29 patients had laparoscopy and 25 had open surgery. Fifty one patients had a malignancy and 3 had benign diseases. Grade I, II, IIIa, IIIb and IVa were 25.6%, 41.1%, 7.7%, 7.7% and 17.9% respectively. No significant difference was noted in the 2 groups. CONCLUSIONS: We believe that in elderly patients, laparoscopic surgery can be offered safely without significantly increasing the surgical risks. The Clavien-Dindo classification is easy to use and effectively applied to categorize post-operative complications associated with nephrectomy/nephroureterectomy in elderly population. However, this system needs slight modification to incorporate intra-operative complications and large studies are needed to validate and standardize this classification for all urological procedures.

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