ABSTRACT
<p><b>OBJECTIVE</b>To assess the feasibility of endobronchial ultrasonography (EBUS) in the differential diagnosis of malignant and benign lesions based on the two characteristic echo features of malignancy.</p><p><b>METHODS</b>EBUS images from 102 patients undergoing bronchoscopy for peripheral lung lesions were analyzed. The sensitivity and specificity were determined for each echo feature, namely the halo sign and low-level echoes that indicated malignancy, or their combination in diagnosing malignant and benign lesions.</p><p><b>RESULTS</b>Low-level echoes showed a sensitivity of 89.46% and a specificity of 83% in the diagnosis of malignancy, both higher than those of the halo sign (69.51% and 65%, respectively). The presence of either of the two echo features had a diagnostic sensitivity of 94.6% for malignant lesions, and the coexistence of the two features had a specificity of 93% for a diagnosis of malignant lesions.</p><p><b>CONCLUSION</b>EBUS is a useful adjunctive modality for lung cancer diagnosis, especially in cases where peripheral lung lesions are invisible in conventional bronchoscopy.</p>