The diagnosis of indeterminate mediastinal lymph nodes, masses, and peripheral pulmonary nodules constitutes a significant challenge. Options for tissue diagnoses include computed tomography-guided percutaneous biopsy, transbronchial fine-needle aspiration, mediastinoscopy, left anterior mediastinotomy, or video-assisted thoracoscopic surgery; however, these approaches have both advantages and limitations in terms of tissue yield, safety profile, and cost. Endobronchial ultrasound (EBUS) is a new minimally invasive technique that expands the view of the bronchoscopist beyond the lumen of the airway. There are two EBUS systems currently available. The radial probe EBUS allows for evaluation of central airways, accurate definition of airway invasion, and facilitates the diagnosis of peripheral lung lesions. Linear EBUS guides transbronchial needle aspiration of hilar and mediastinal lymph nodes, improving diagnostic yield. This article will review the principles and clinical applications of EBUS, and will highlight the role of this new technology in the diagnosis and staging of lung cancer.

A ppropriate staging of lung cancer is critical, as it predicts prognosis and dictates treatment. Radiographic staging with CT scan and PET scan can offer clues to the extent of disease, but pathologic confi rmation of malignancy and determination of the TNM stage for non-small cell lung cancer (NSCLC) dictates the treatment choice. 1 In practice, mediastinal lymph node involvement most often differentiates those who are surgical candidates from those who are not. 2 The current methods available to adequately stage the mediastinum include mediastinoscopy, videoassisted thoracoscopy, endoscopic ultrasound (EUS), endobronchial ultrasound (EBUS), transthoracic needle aspiration, and transbronchial needle aspiration. The American College of Chest Physicians practice guidelines state that "tissue should be obtained by whatever method is easiest to perform" depending on the size and location of the lymph node, the availability of the technology, and expertise in the local facility. 1 EBUS and EUS have gained acceptance as dependable procedures to stage lung cancer with comparable accuracy to surgical methods. 1,[3][4][5] The use of ultrasound facilitates the direct visualization of the lymph node during biopsy and may offer information regarding nodal characteristics of malignant nodes.Purpose: Reliable staging of the mediastinum determines TNM classifi cation and directs therapy for non-small cell lung cancer (NSCLC). Our aim was to evaluate predictors of mediastinal lymph node metastasis in patients undergoing endobronchial ultrasound (EBUS). Methods: Patients with known or suspected lung cancer undergoing EBUS for staging were included. Lymph node radiographic characteristics on chest CT/PET scan and ultrasound characteristics of size, shape, border, echogenicity, and number were correlated with rapid on-site evaluation (ROSE) and fi nal pathology. Logistic regression (estimated with generalized estimating equations to account for correlation across nodes within patients) was used with cancer (vs normal pathology) as the outcome. ORs compare risks across groups, and testing was performed with two-sided a of 0.05. Results: Two hundred twenty-seven distinct lymph nodes (22.5% positive for malignancy) were evaluated in 100 patients. Lymph node size, by CT scan and EBUS measurements, and round and oval shape were predictive of mediastinal metastasis. Increasing size of lymph nodes on EBUS was associated with increasing malignancy risk ( P 5 .0002). When adjusted for CT scan size, hypermetabolic lymph nodes on PET scan did not predict malignancy. Echogenicity and border contour on EBUS and site of biopsy were not signifi cantly associated with cancer. In 94.8% of lymph nodes with a clear diagnosis, the ROSE of the fi rst pass correlated with subsequent passes. Conclusions: Lymph node size on CT scan and EBUS and round or oval shape by EBUS are predictors of malignancy, but no single characteristic can exclude a visualized lymph node from biopsy. Further, increasing the number of samples taken is unlikely to signifi cant...

When faced with a patient with a pulmonary nodule, it is incumbent on the clinician to differentiate benign cases from cancer. Although most clinicians use clinical experience to estimate the probability of malignancy in pulmonary nodules, some rely on one or T he pulmonary nodule is a single, spherical, wellcircumscribed, radiographic opacity that measures , 3 cm in diameter and is completely surrounded by aerated lung. There is no associated atelectasis, hilar enlargement, or pleural effusion. 1 Approximately 150,000 such nodules are identifi ed each year according to dated estimates. 2,3 The incidence is likely much higher than this because of the increasing use of chest CT scan for the evaluation of a myriad of pulmonary symptoms and disorders. The National Lung Screening Trial has shown screening patients with low-dose CT (LDCT) scanning led to a relative risk reduction in death from lung cancer by 20%. 4 Over the 3-year screening period, however, 39.1% of the participants in the LDCT scanning group had a nodule discovered, of which (96.4%) were benign. 4 Currently, 7 million Americans meet the National Lung Screening Trial screening criteria. 4,5 Even if only one-fourth of those eligible are screened, a possible 680,000 new nodules could be discovered over 3 years.Background: An estimated 150,000 pulmonary nodules are identifi ed each year, and the number is likely to increase given the results of the National Lung Screening Trial. Decision tools are needed to help with the management of such pulmonary nodules. We examined whether adding any of three novel functions of nodule volume improves the accuracy of an existing malignancy prediction model of CT scan-detected nodules. Methods: Swensen's 1997 prediction model was used to estimate the probability of malignancy in CT scan-detected nodules identifi ed from a sample of 221 patients at the Medical University of South Carolina between 2006 and 2010. Three multivariate logistic models that included a novel function of nodule volume were used to investigate the added predictive value. Several measures were used to evaluate model classifi cation performance. Results: With use of a 0.5 cutoff associated with predicted probability, the Swensen model correctly classifi ed 67% of nodules. The three novel models suggested that the addition of nodule volume enhances the ability to correctly predict malignancy; 83%, 88%, and 88% of subjects were correctly classifi ed as having malignant or benign nodules, with signifi cant net improved reclassifi cation for each ( P , .0001). All three models also performed well based on Nagelkerke R 2 , discrimination slope, area under the receiver operating characteristic curve, and Hosmer-Lemeshow calibration test. Conclusions:The fi ndings demonstrate that the addition of nodule volume to existing malignancy prediction models increases the proportion of nodules correctly classifi ed. This enhanced tool will help clinicians to risk stratify pulmonary nodules more effectively.CHEST 2014; 145(3):464-472

To satisfy human needs and desires, it is necessary to produce goods and services that require the use of some production factors, such as labor, capital, and energy, among others. Nowadays, energy is a key production factor for economic activity in all countries. The main objective of this paper is to analyze the relationship between energy, economic growth, urbanization, and financial development in the country-members of the North American Free Trade Agreement (NAFTA) during the period of 1971-2015. Panel data Econometric methods are applied in this research, namely cross-section dependence (Pesaran test), unit root (Cross-sectional Augmented Dickey Fuller and Cross-sectional Im, Pesaran, and Shin tests), cointegration (Kao and Fisher-Johansen tests), and heterogeneous causality (Hurlin and Dumitrescu test). The results achieved in this research demonstrate that the variables of this model are characterized by a cross-section dependence, and they are integrated in order one. An equilibrium or long-term relationship between them exists. By means of the Fully Modified OLS and Dynamic OLS estimators it this demonstrated that there is a positive relationship between GDP and EC, while there is a negative relationship between FD, CPI, URB, and TO and EC. The economic policy recommendations drawn from this investigation are that financial development promotion, urbanization, and trade openness may contribute to reducing energy consumption in these countries. Appl. Sci. 2019, 9, 302 2 of 11 transparency among borrowers and lenders, fosters greater flows of financial capital and investment, and facilitates access to more efficient energy products, among other things, which can affect the demand for energy by increasing consumption and business investments [3,4]. Financial development affects the demand for energy through the following: (a) it allows consumers to access easier and cheaper loans of money to buy durable goods, such as cars, houses, refrigerators, washing machines, etc., which are large energy consumers that can affect the total energy demand of a country; (b) it allows businesses to access easier and less expensive financial capital, which can help create a new business or expand existing ones, such as buying or building more plants, employing more workers, and buying machinery and equipment [3,4].The economy, energy, and the environment are three important elements for the development of nations because the use of energy is vital to the world economy in the present and in the future. However, an increase in energy use generates increases in carbon dioxide (CO 2 ) emissions, which cause environmental problems [5]. It would be expected that greater economic growth and economic development are related to higher levels of electricity and energy consumption in general; moreover, a greater amount of CO 2 emissions and resources from financial markets are required to fund economic development [6]. However, there are also authors who argue that financial development facilitates the reduction of energy consump...

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