Radial endobronchial ultrasound - guided bronchoscopy for the diagnosis of peripheral pulmonary lesions: A systematic review and meta-analysis of prospective trials

Background: The diagnostic yield of radial endobronchial ultrasound (r-EBUS) for the diagnosis of peripheral pulmonary lesions (PPLs) varies between studies and is affected by multiple factors. We aimed to evaluate the efficacy and safety of r-EBUS, and to explore the factors influencing the diagnostic yield of r-EBUS in patients with PPLs. Methods: The PubMed, Web of Science, and EMBASE databases were searched to identify relevant studies that used r-EBUS for diagnosing PPLs from the date of inception to Dec 2022. Metaanalysis was conducted using Review Manager 5.4 and Stata 15.1. Results: An analysis of 46 studies with a total of 7252 PPLs was performed. The pooled diagnostic yield of r-EBUS was 73.4 % (95 % CI: 69.9%-76.7 %), with significant heterogeneity detected among studies (I-2 = 90 %, P < 0.001). Further analysis demonstrated PPLs located in the middle or lower lobe, >2 cm in size, malignant in type, solid in appearance on computerized tomography (CT), present in bronchus sign, the within probe location, and the addition of rapid on-site evaluation (ROSE) were associated with increased diagnostic yield, whereas use of a guide sheath (GS), bronchoscopy type, and a multimodality approach failed to influence the outcome. The pooled incidence rates of overall complications, pneumothorax and moderate and severe bleeding were 3.1 % (95 % CI: 2.1%-4.3 %), 0.4 % (95 % CI: 0.1%-0.7 %) and 1.1 % (95 % CI: 0.5%-2.0 %), respectively. Conclusions: r-EBUS has an appreciable diagnostic yield and an excellent safety manifestation when used to deal with PPLs.