Comparison of the diagnostic effect of EBUS-TBNA versus conventional bronchoscopic biopsy in patients with lung cancer who exhibit external bronchial stenosis

To investigate the effectiveness of endobronchial ultrasound-guided transbronchial needle aspiration(EBUS-TBNA) technology in patients with external bronchial stenosis who have lung cancer. <bold>Methods:</bold> Retrospective analysis was performed on the data of patients with mediastinal and/or hilar lymph node enlargement accompanied by external bronchoconstriction on chest CT in Beijing Friendship Hospital between July 2018 and November 2021, who underwent conventional electronic bronchoscopy and EBUS examination sequentially and were ultimately diagnosed with lung cancer. The diagnostic accuracy of both techniques was evaluated. <bold>Results:</bold> A total of 46 patients underwent both techniques. The diagnostic accuracy of EBUS-TBNA was significantly higher than that of conventional bronchoscopy biopsy for both cytologic(84.8% vs.43.5%,p＜0.001) and histological specimens(82.6% vs.50.0%,p=0.001), and comprehensive specimens(84.8% vs.58.7%,p=0.005). There was a significant improvement in the thinprep cytologic test(TCT) diagnostic accuracy of EBUS-TBNA(78.3% vs.39.1%,p＜0.001). Furthermore, the diagnostic accuracy of lesions with a short diameter ≤ 3cm was considerably increased by EBUS-TBNA(82.9% vs.60.0%,p=0.034). For SCLC, the diagnosis accuracy of EBUS-TBNA TCT was significantly higher than that of NSCLC(90.9% vs.66.7%,p= 0.046). <bold>Conclusions:</bold> As lung cancer manifests as external bronchial stenosis, EBUS-TBNA can significantly increase the diagnostic accuracy of the procedure, particularly for lesions with a diameter ≤ 3cm. EBUS-TBNA TCT is a useful adjunct to EBUS-TBNA since its diagnostic accuracy for SCLC is higher than that of NSCLC.