Diagnostic Value of Elastography and Endobronchial Ultrasound in the Study of Hilar and Mediastinal Lymph Nodes

Abstract

Background: The aim of this study was to explore elastography features and its ability to distinguish between benign and malignant lymph nodes by comparing the results with an anatomopathologic examination used as gold standard. Methods: Patients were randomized in 2 groups [endobronchial ultrasound (EBUS) and EBUS-elastography]. Echographic characteristics of the lymph nodes were collected in both categories. In the EBUS-elastography group, elastographic data were also determined. Results: A total of 100 lymph nodes were evaluated. Group 1 (EBUS) consisted of 57 lymph nodes. Group 2 (EBUS-elastography) included 43 lymph nodes. In group 2, lymph nodes with predominantly blue pattern were associated with a pathologic determination of malignancy, and the probability of presenting malignant infiltration with this color pattern was 86.7% (P=0.00004). Malignant lymph nodes presented less color dispersion (48.8 vs. 94.8, P=0.00013), higher ratio of blue pixels (66% vs. 32.5%, P=0.016), and higher strain ratio (7.1 vs. 2.48, P=0.005). The cut-off points to distinguish between benign and malignant lymph nodes were 4 for strain ratio, 61 for frequency histograms, and 52 for blue pixel ratio. The area under the curve of the ROC curves were 0.75, 0.83, and 0.87, respectively. Group 2 presented a lower number of nondiagnostic samples (2.3% vs. 21%, P=0.001) and a higher rate of malignant results (42% vs. 16%, P=0.005). Conclusion: EBUS-elastography is feasible during EBUS and may be helpful in predicting malignant lymph node infiltration. It could improve anatomopathologic sample collection and increase diagnostic efficiency.

CT texture analysis of mediastinal lymphadenopathy: Combining with US-based elastographic parameter and discrimination between sarcoidosis and lymph node metastasis from small cell lung cancer

“…Elastography has been frequently used for the diagnosis of breast cancer, and the FLR has been reported to be useful for differentiating between benign and malignant breast lesions [16,17]. Elastographic assessments of mediastinal lymph nodes have also been performed; it has been reported that EBUS elastography can be used an indicator for distinguishing between malignant and benign lymph nodes [11][12][13][14]. In this study, among the 19 patients who underwent EBUS elastography, the FLR values were significantly higher in those with SCLC than in those with sarcoidosis.…”

“…The technique of EBUS-TBNA has rapidly developed over recent years. During the process of EBUS-TBNA, the biopsied lymph node can be visualized on ultrasound imaging; and ultrasound elastography of the lymph node of interest has been investigated as a method for distinguishing between benign and malignant lymph nodes [11][12][13][14]. Although discriminating between benign and malignant lymph nodes by elastography alone has been difficult [15], it has been suggested that the fat-to-lesion strain ratio (FLR) determined by elastography is useful for differentiating between benign and malignant lesions outside of the mediastinum, particularly for breast cancer [16][17][18].…”

Recent advances in convex probe endobronchial ultrasound: a narrative review

“…In 2019, research on elastography still focused on judging lesions. Two studies found that the consistency rates of Type 3 lymph nodes with pathology were 80.7% (5) and 73% (6), and results having no significant correlation with the maximum standardized uptake value of positron emission tomography-computed tomography (PET-CT) images (5). From the above findings, elastography has been shown to help distinguish benign from malignant growths, but cannot replace needle aspiration biopsy.…”

Convex probe endobronchial ultrasound: historical, contemporary, and cutting-edge applications

“…The CP-EBUS bronchoscope is connected to an ultrasound processor that allows record the patient information, measure the lesion, label, adjust the scanning range (the typical default 4 cm range permits to visualize best most of the hilar, mediastinal and vascular structures), regulate the gain to improve imaging, use of color/power flow to help identify vascular structures, or perform elastography to identify different strain/stiffness in the tissue (61)(62)(63). Several dedicated aspiration needles are available allowing real-time EBUS-TBNA.…”