Association between lesion angle on endobronchial ultrasound and biopsy utility in diagnosing peripheral pulmonary lesions: a retrospective analysis.

<bold>Background:</bold> Endobronchial ultrasound (EBUS)-guided transbronchial lung biopsy (TBLB) is a widely accepted diagnostic method for peripheral pulmonary lesions (PPLs). However, the diagnostic yield of this procedure varies. The aim of this study is to investigate the factors that affect the diagnostic efficacy of EBUS-TBLB, especially the angle of the lesion. <bold>Methods:</bold> The medical records of 456 patients with 461 PPLs who underwent TBLB using EBUS were retrospectively reviewed and analyzed to identify factors that predict the diagnostic yield of TBLB using EBUS in PPLs. The differences of the diagnostic yield based on the angle of the lesion were also analyzed. <bold>Results:</bold> After conducting a multivariate logistic regression analysis, only the lesion angle (OR 0.465, 95% CI 0.237-0.911, P=0.026) and lesion nature (OR 8.255, 95% CI 4.947-13.776, P<0.001) have a statistically significant correlation with the diagnostic yield of PPL. We then conducted a subgroup analysis based on the angle and nature of the lesions. The results showed a positive correlation between the angle of malignant lesions and the diagnostic rate (57.1%, 60.7%, 65.0%, 71.4%, and 76.3%, respectively). However, no such correlation was observed in benign lesions. <bold>Conclusion:</bold> The angle and nature of lesions are potential factors in predicting the diagnostic yield of TBLB using EBUS for PPLs. For malignant lesions, there may be a positive correlation between the angle of the lesion and the diagnostic rate.