Endobronchial Ultrasound Elastography for Evaluation of Intrathoracic Lymph Nodes: A Pilot Study

Abstract

Background: Endobronchial ultrasound (EBUS) elastography is a new imaging procedure for describing the elasticity of intrathoracic lesions and providing important additional diagnostic information. Objectives: The aim of this study was to utilize the feasibility of qualitative and quantitative methods to evaluate the ability of EBUS elastography to differentiate between benign and malignant mediastinal and hilar lymph nodes (LNs) during EBUS-guided transbronchial needle aspiration (EBUS-TBNA). Methods: Patients with enlarged intrathoracic LNs required for EBUS-TBNA examination at a clinical center for thoracic medicine from January 2014 to April 2014 were prospectively enrolled. EBUS sonographic characteristics on B-mode, vascular patterns and elastography, EBUS-TBNA procedures, pathological findings, and microbiological results were recorded. Furthermore, elastographic patterns (qualitative method) and the mean gray value inside the region of interest (quantitative method) were analyzed. Both methods were compared with a definitive diagnosis of the involved LNs. Results: Fifty-six patients including 68 LNs (33 benign and 35 malignant nodes) were prospectively enrolled into this study and retrospectively analyzed. Using qualitative and quantitative methods, we were able to differentiate between benign and malignant LNs with high sensitivity, specificity, positive and negative predictive values, and accuracy (85.71, 81.82, 83.33, 84.38, and 83.82% vs. 91.43, 72.73, 78.05, 88.89, and 82.35%, respectively). Conclusions: EBUS elastography is potentially capable of further differentiating between benign and malignant LNs. These proposed qualitative and quantitative methods might be useful tools for describing EBUS elastography during EBUS-TBNA.

Endobronchial Ultrasound Elastography Differentiates Intrathoracic Lymph Nodes: A Meta-Analysis

“…In the study by He and colleagues [17], the quantitative method of strain ratio showed a better diagnostic yield than the semiquantitative method of the elastography score. However, in the studies by Sun [19] and Huang [21] and their colleagues, the elastography score showed better performance than the quantitative method of mean grey value. In our meta-analysis, the semiquantitative method showed a good specificity compared with the quantitative method, and there was no significant difference for the sensibility between those subgroups.…”

“…Our literature search yielded 36 publications for consideration, 29 of which were excluded for the following reasons: 10 were review articles or comments, two were case reports, three were not written in English, seven were a letter to editor or meeting abstract, and the seven were not specified (Fig 1). The remaining seven publications met all of the inclusion criteria and were included for this meta-analysis [10,11,[17][18][19][20][21].…”

“…Huang and colleagues [21] and Korrungruang and colleagues [20] adopted the similar classification method in their studies. However, He [17] and Sun [19] and their colleagues chose four or five types for classification [17,19]. In contrast to the semiquantitative methods, quantitative methods mostly relied on computer-aided calculation, and thereby overcame the bias of artificial judgments.…”

“…Although their results were similar, the cutoff values for these three studies were 32.07, 8, and 2.5, respectively. Sun and colleagues [19] selected a new method, the "mean grey value," to describe the stiffness of target lesions. A new algorithm in which the image was first quantized and then clustered in the quantized color space in prior segmentation part was introduced by Nakajima and colleagues [10].…”

Diagnostic Accuracy of Interleukin-27 between Tuberculous Pleural Effusion and Malignant Pleural Effusion: A Meta-Analysis

“…After all, except TB, the most likely result is malignancy if a patient with exudative PE has predominantly lymphocytes. Sun et al [23] concluded that endobronchial ultrasound elastography is a promising method that is used for the identification of benign and malignant lymph nodes with high SEN, SPE, and predictive accuracy, which may offer important supplementary information in endobronchial ultrasound-guided transbronchial needle aspiration cases. Karpathiou et al [24] also raise the issue that pleural frozen sections are a valuable and accurate tool in immediately diagnosing malignancy, permitting further operations like pleurodesis in the meantime.…”