Value of adding ultrathin bronchoscopy to thin bronchoscopy for peripheral pulmonary lesions: A multicentre prospective study

Background and Objective: The diagnostic yield of thin bronchoscopy with radial probe endobronchial ultrasound (rEBUS) of peripheral pulmonary lesions into which the rEBUS probe cannot be inserted is unsatisfactory. In such cases, adding ultrathin bronchoscopy may be an option. We evaluated the efficacy of sequential ultrathin bronchoscopy for peripheral pulmonary lesions into which the rEBUS probe could not be inserted during thin bronchoscopy. Methods: In this multicentre prospective study, patients with peripheral pulmonary lesions ≤30 mm in diameter underwent rEBUS-guided transbronchial biopsy using a 4.0 mm diameter thin bronchoscope. In patients with lesions into which a rEBUS probe could not be inserted using that bronchoscope, bronchoscopy using a 3.0 mm diameter ultrathin bronchoscope was performed. Results: A total of 342 patients were enrolled and 340 were analysed. Among them, 87 patients with lesions of a median longest diameter of 17.5 mm underwent thin bronchoscopy followed by ultrathin bronchoscopy. Of the 87 patients, the rEBUS probe was successfully inserted into the lesions via the ultrathin bronchoscope in 50 patients (57.5%). Of the 87 patients, the diagnostic yields of thin bronchoscopy and ultrathin bronchoscopy were 12.6% (11 of 87) and 41.4% (36 of 87), respectively (p < 0.001). Conclusion: Ultrathin bronchoscopy affords a higher diagnostic yield for lesions into which a rEBUS probe cannot be inserted via a thin bronchoscope.