Background: To investigate the value of endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) in the diagnosis of lung nodules related enlarged mediastinal lymph nodes (MLNs).
Methods: Clinical data of 108 patients with lung nodules related enlarged MLNs who underwent EBUS-TBNA in our single center were retrospectively analyzed from January 2020 to December 2021. The sensitivity and specificity of EBUS-TBNA in malignancy diagnosis were evaluated. Associations between ultrasonic image measurement indexes and malignancy diagnosis were explored. The receiver operating characteristic (ROC) curve of these indexes, the area under curve (AUC), and the corresponding cut-off values were calculated to predict malignant MLNs.
Results: Sensitivity, specificity, and accuracy of EBUS-TBNA in the diagnosis of lung nodules related malignant MLNs were 89.47%, 100%, and 92.59%, respectively. There were significantly higher proportions of malignant MLNs with clear boundary, short diameter ≥1 cm, lower long to short diameter ratio, abundant flow of blood, and destructed medulla than that of benign ones (P < .05). According to ROC curve analysis, the cut-off value of short diameters for predicting malignant MLNs was 1.085 cm, and the AUC was 0.796 (95% confidence interval: 0.724-0.868, P < .001). Corresponding sensitivity and specificity were 61.36% and 80.00%, respectively. The cut-off value of the long to short diameter ratio for predicting malignancy was 1.405, and the AUC was 0.697 (95% confidence interval: 0.609-0.790, P < .001). Corresponding sensitivity and specificity were 70.00% and 71.97%, respectively.
Conclusion: EBUS-TBNA has a satisfactory accuracy of lung nodules related MLNs diagnosis. Short diameters and long to short diameter ratio of lung nodules related MLNs in ultrasonic image may contribute to the prediction of malignant lymph nodes.